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2026-09-11tracing: Fix memory corruption from the histogram stacktrace modifierDonggeun Yoo
parse_field() sets HIST_FIELD_FL_STACKTRACE from the ".stacktrace" modifier before it looks the field name up, and nothing afterwards checks that the name resolved to a field which holds a stacktrace. create_hist_field() picks HIST_FIELD_FN_STACK on the strength of the field pointer alone, which reads a __data_loc word from the record and follows its low 16 bits as an offset into the same record. event_hist_trigger() takes the first word there as an entry count and copies that many longs into a 31 entry array: n_entries = *stack; memcpy(entries, ++stack, n_entries * sizeof(unsigned long)); Neither end of that copy is bounded, and the count is whatever the event holds at the offset, so any field will do: # cd /sys/kernel/tracing/events/sched/sched_process_fork # echo 'hist:keys=parent_pid.stacktrace' > trigger # (true) BUG: kernel NULL pointer dereference, address: 0000000000000008 RIP: 0010:rb_insert_color+0x18/0x130 timerqueue_linked_add+0x7e/0xd0 enqueue_hrtimer+0x39/0xb0 __hrtimer_run_queues+0x10f/0x1f0 </IRQ> RIP: 0010:memcpy+0xc/0x30 event_hist_trigger+0x165/0x690 The timer interrupt landed on the rbtree the copy had already run over. No debug options are needed for this; KASAN reports the same write as an out-of-bounds read of 13835058055416381440 bytes. Documentation/trace/histogram.rst already states the rule, "must be a long[] type", so enforce it once the name has been resolved. Names which resolve to no field at all, "hitcount.stacktrace" and the common_* pseudo-fields, are refused for the same reason: they hold no stacktrace to read. Cc: stable@vger.kernel.org Fixes: cc5fc8bfc961 ("tracing/histogram: Add stacktrace type") Link: https://patch.msgid.link/20260907155045.692664-2-donggeunyoo.kernel@gmail.com Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-11tracing: Undo the registration when enabling the histogram trigger failsDonggeun Yoo
Commit 6f86bdeab633 ("tracing: Fix bad hist from corrupting named_triggers list") described how a trigger that is registered but not on file->triggers ends up freed while still on the global named_triggers list, and moved the registration down so that hist_trigger_enable() follows it immediately. One path still gets there. hist_trigger_enable() adds the trigger and takes it straight back out when the event cannot be enabled: list_add_tail_rcu(&data->list, &file->triggers); update_cond_flag(file); if (trace_event_trigger_enable_disable(file, 1) < 0) { list_del_rcu(&data->list); update_cond_flag(file); ret--; } so the list walk in hist_unregister_trigger() matches nothing, test stays NULL, and the ->free() that would call del_named_trigger() is skipped. out_unreg falls through to out_free, which frees the trigger anyway: BUG: KASAN: slab-use-after-free in find_named_trigger+0xac/0xc0 Read of size 8 at addr ffff8880091d3160 by task init/1 find_named_trigger+0xac/0xc0 hist_register_trigger+0xc1/0xa00 event_hist_trigger_parse+0x3146/0x6af0 event_trigger_write+0xce/0x160 Freed by task 69: kfree+0x154/0x420 trigger_kthread_fn+0xfd/0x160 Leave the trigger where hist_unregister_trigger() can find it and let that undo the registration, which is the only code that knows all of what cmd_ops->init() took: the named list entry, the hist_pad reference, the reference on the trigger a named histogram is shared with, and the copied cmd_ops. It also pairs the failed trace_event_trigger_enable_disable(), whose sm_ref and buffered event reference are otherwise left behind. Since ->free() releases trigger_data and, for a trigger that does not share its histogram, hist_data with it, out_unreg can no longer fall through to out_free. For a trigger that does share, hist_register_trigger() has already destroyed the caller's hist_data, so the fall-through was reading freed memory there as well. Move the enable_timestamps check in hist_unregister_trigger() above the ->free() call for the same reason: hist_data does not outlive it once the trigger being removed is the one that owns it. Cc: stable@vger.kernel.org Fixes: 067fe038e70f ("tracing: Add variable reference handling to hist triggers") Reported-by: Sashiko AI <sashiko-bot@kernel.org> Closes: https://lore.kernel.org/linux-trace-kernel/20260907092944.3950E1F00A3D@smtp.kernel.org/ Link: https://patch.msgid.link/20260907124420.607097-3-donggeunyoo.kernel@gmail.com Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-11tracing: Take the reference before publishing the named histogram triggerDonggeun Yoo
event_hist_trigger_named_init() puts the trigger on the global named_triggers list and only then takes the reference on the trigger it shares its histogram with: data->ref++; save_named_trigger(data->named_data->name, data); ret = event_hist_trigger_init(data->named_data); if (ret < 0) { kfree(data->cmd_ops); data->cmd_ops = &trigger_hist_cmd; } return ret; event_hist_trigger_init() fails when alloc_hist_pad() cannot allocate, and nothing takes the trigger back off the list on the way out. event_hist_trigger_parse() frees it, and the next lookup by name reads the freed object: BUG: KASAN: slab-use-after-free in find_named_trigger+0xac/0xc0 Read of size 8 at addr ffff888009346860 by task init/1 find_named_trigger+0xac/0xc0 hist_register_trigger+0xc1/0xa00 event_hist_trigger_parse+0x3146/0x6af0 event_trigger_write+0xce/0x160 Freed by task 67: kfree+0x154/0x420 trigger_kthread_fn+0xfd/0x160 Do the reference first and publish once it has succeeded, so that nothing which can fail runs after the trigger becomes findable. Cc: stable@vger.kernel.org Fixes: 7ab0fc61ce73 ("tracing: Move histogram trigger variables from stack to per CPU structure") Reported-by: Sashiko AI <sashiko-bot@kernel.org> Closes: https://lore.kernel.org/linux-trace-kernel/20260907092944.3950E1F00A3D@smtp.kernel.org/ Link: https://patch.msgid.link/20260907124420.607097-2-donggeunyoo.kernel@gmail.com Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com> Acked-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-11tracing: Set the trace clock before registering the histogram triggerDonggeun Yoo
hist_register_trigger() puts the trigger on the global named_triggers list in cmd_ops->init(), and only then sets the trace clock: if (data->cmd_ops->init) { ret = data->cmd_ops->init(data); if (ret < 0) goto out; } if (hist_data->enable_timestamps) { ret = tracing_set_clock(file->tr, hist_data->attrs->clock); if (ret) { hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); goto out; } The clock string is not checked anywhere before that call, so a named trigger using common_timestamp with an unknown clock fails after it has already become findable. event_hist_trigger_parse() then frees it without taking it off the list, and the next lookup by name reads the freed object: ~# cd /sys/kernel/tracing/events/sched/sched_switch ~# echo 'hist:name=foo:keys=common_pid:ts=common_timestamp:clock=bogus' > trigger bash: echo: write error: Invalid argument ~# echo 'hist:name=foo:keys=common_pid' > trigger BUG: KASAN: slab-use-after-free in find_named_trigger+0xac/0xc0 Read of size 8 at addr ffff88800915d760 by task init/1 find_named_trigger+0xac/0xc0 hist_register_trigger+0xc1/0x900 event_hist_trigger_parse+0x3146/0x6af0 event_trigger_write+0xce/0x160 Freed by task 63: kfree+0x154/0x420 trigger_kthread_fn+0xfd/0x160 Set the clock before the trigger is registered, so that nothing which can fail runs after it is published, the way commit 6f86bdeab633 ("tracing: Fix bad hist from corrupting named_triggers list") moved the registration below the rest of the setup. tracing_set_filter_buffering() is reference counted, so the init failure path has to drop the reference that the clock block now takes first. Cc: stable@vger.kernel.org Fixes: a4072fe85ba3 ("tracing: Add a clock attribute for hist triggers") Link: https://patch.msgid.link/20260907091415.554535-1-donggeunyoo.kernel@gmail.com Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-11tracing: Fix typo "availabe" in commentHemanth Selam
Correct "availabe" to "available", reported by scripts/checkpatch.pl using the misspelling list in scripts/spelling.txt. Only touches comments, no code changes. Link: https://patch.msgid.link/20260907062608.13924-1-hemanth.selam@gmail.com Assisted-by: Cursor:claude-opus-5 Signed-off-by: Hemanth Selam <hemanth.selam@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-11tracing: Let histogram values keep the percent and graph modifiersDonggeun Yoo
The .percent and .graph modifiers exist only for histogram values, but a value carrying either of them has been rejected since v6.3. The example in Documentation/trace/histogram.rst, # echo 'hist:keys=prev_comm:vals=hitcount.percent:nohitcount' > \ events/sched/sched_switch/trigger returns -EINVAL. parse_field() sets the two flags only when the field is neither a key nor a variable, that is, only on a value: } else if (strncmp(modifier, "percent", 7) == 0) { if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) goto error; *flags |= HIST_FIELD_FL_PERCENT; __create_val_field() then rejects a value for carrying them, so no field can reach hist_trigger_print_val(), where both are implemented. commit e0213434fe3e ("tracing: Do not let histogram values have some modifiers") added the check after a value with .buckets oopsed in hist_field_name(). That happens because .buckets and .log2 make create_hist_field() build a nested field in operands[0] which hist_field_name() then walks into. The percent and graph flags do not create an operand and are not read by hist_field_name(); they are only used when printing a value. Stop rejecting the two flags on a value. The check for variables is left alone, where they are unreachable anyway because parse_field() rejects a variable carrying them first. With the two flags removed, the trigger above installs and prints as documented: { prev_comm: rcu_preempt } hitcount (%): 0.00 { prev_comm: init } hitcount (%): 99.98 Totals: Hits: 237896 Cc: stable@vger.kernel.org Fixes: e0213434fe3e ("tracing: Do not let histogram values have some modifiers") Link: https://patch.msgid.link/20260907052113.430818-1-donggeunyoo.kernel@gmail.com Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-11tracing: Keep the entry count when the histogram stats allocation failsDonggeun Yoo
print_entries() uses n_entries both as the number of sort entries and as its own return value, so the -ENOMEM it stores when the stats allocation fails overwrites the count that the cleanup still needs: n_entries = tracing_map_sort_entries(map, ...); if (n_entries < 0) return n_entries; ... if (!stats) { n_entries = -ENOMEM; goto out; } ... out: tracing_map_destroy_sort_entries(sort_entries, n_entries); tracing_map_destroy_sort_entries() takes an unsigned int and loops up to it, so -ENOMEM arrives as 4294967284. It walks an array of at most map->max_elts pointers and calls destroy_sort_entry(), which dereferences and frees, on whatever lies past the end. Reading the hist file of a trigger with a .percent value, with that allocation forced to fail: BUG: KASAN: vmalloc-out-of-bounds in tracing_map_destroy_sort_entries+0xa0/0xb0 Read of size 8 at addr ffffc90000045000 by task init/1 tracing_map_destroy_sort_entries+0xa0/0xb0 hist_show+0x6f7/0x1df0 seq_read_iter+0x2b8/0x1190 vfs_read+0x176/0xa40 The buggy address belongs to a 4-page vmalloc region starting at ffffc90000041000 allocated at tracing_map_sort_entries+0x5c/0xd50 A few pages further the fault is fatal. The registers at the oops confirm the bound: the loop's end pointer less the array start, over the pointer size, is 4294967284. Return the error in a separate variable and leave n_entries holding the count, the way tracing_map_sort_entries() does on its own error path. The stats block is only entered for a value carrying .percent or .graph, which __create_val_field() has rejected since v6.3, so this cannot be reached in mainline as it stands. It becomes reachable again with "tracing: hist: let values keep the percent and graph modifiers", so it should be applied first. Cc: stable@vger.kernel.org Fixes: abaa5258ce5e ("tracing: Add .percent suffix option to histogram values") Link: https://patch.msgid.link/20260907060323.480728-1-donggeunyoo.kernel@gmail.com Reported-by: sashiko-bot@kernel.org Closes: https://lore.kernel.org/all/20260907053113.1CED91F00A3A@smtp.kernel.org/ Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-11tracing: Free histogram the field rejected for a bad modifierDonggeun Yoo
Writing a hist trigger whose value or variable carries a modifier that is not allowed there leaks the fields that were built for it. __create_val_field() takes the field from parse_expr() and stores it in hist_data->fields[] only after the modifier checks have run: hist_field = parse_expr(hist_data, file, field_str, flags, var_name, &n_subexprs); ... if (hist_field->flags & HIST_FIELD_FL_VAR) { if (hist_field->flags & (...)) goto err; } else { if (hist_field->flags & (...)) goto err; } hist_data->fields[val_idx] = hist_field; Both checks jump past that store, and the err label returns without freeing anything. The error unwinds to create_hist_data(), which calls destroy_hist_data() -> destroy_hist_fields(), and that reaches a field only by walking fields[]. A field that never got there is unreachable. commit e0213434fe3e ("tracing: Do not let histogram values have some modifiers") set ret to -EINVAL and fell through to the store, which left the field owned by fields[] and freed along with the rest of hist_data. Splitting the check into a value case and a variable case replaced that fall-through with a goto that skips it. With CONFIG_DEBUG_KMEMLEAK, 200 writes of # echo 'hist:keys=prev_pid:vals=next_pid.log2' > \ events/sched/sched_switch/trigger each correctly rejected with -EINVAL, leave 332 unreferenced objects (63744 bytes) reported at create_hist_field(); 200 install and remove cycles of a valid trigger leave none. A '.log2' field is two allocations, since create_hist_field() puts the plain field in operands[0] of the log2 field, and both are reported. Use destroy_hist_field() rather than __destroy_hist_field() so that operands[0] is freed as well. It returns early for HIST_FIELD_FL_VAR_REF, which is what an operand owned by hist_data->var_refs[] needs; the rejected field itself is never a var ref, because a var ref never carries a modifier flag. Cc: stable@vger.kernel.org Fixes: e30fbc618e97 ("tracing/histograms: Allow variables to have some modifiers") Link: https://patch.msgid.link/20260907034948.240387-1-donggeunyoo.kernel@gmail.com Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-11tracing: Free histogram the var ref when its initialization failsDonggeun Yoo
create_var_ref() allocates a VAR_REF hist_field and then calls init_var_ref() to fill it in. When that fails the field is leaked. commit 656fe2ba85e8 ("tracing: Use hist trigger's var_ref array to destroy var_refs") made destroy_hist_field() return early for HIST_FIELD_FL_VAR_REF, since var refs are freed by walking the trigger's var_refs[] array instead. create_var_ref() adds the field to that array only after init_var_ref() has succeeded, so on this path the field is in neither place and nothing frees it. The call was correct when it was written, before var refs were taken out of destroy_hist_field(). init_var_ref() cannot free it either. The caller owns the field, so init_var_ref() undoes only its own string allocations and leaves the field alone. Freeing it there would leave create_var_ref() passing freed memory to destroy_hist_field(), which reads its flags. Call __destroy_hist_field(), which frees the field without consulting the flag. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260906133352.3815019-1-donggeunyoo.kernel@gmail.com Fixes: 656fe2ba85e8 ("tracing: Use hist trigger's var_ref array to destroy var_refs") Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-11tracing: Free histogram var refs regardless of how often they are referencedDonggeun Yoo
Using the same variable three or more times in one hist trigger leaks the variable reference and its strings when the trigger is removed. commit 656fe2ba85e8 ("tracing: Use hist trigger's var_ref array to destroy var_refs") made a trigger's var_refs[] array the only owner of a var ref: destroy_hist_field() returns early for HIST_FIELD_FL_VAR_REF, so the field expressions never destroy one. One entry, freed once, no count needed. commit 8bcebc77e85f ("tracing: Fix histogram code when expression has same var as value") then made repeated references share one object and added a count of them. Only the increment side exists, since those expressions still return early and never drop a reference, so __destroy_hist_field() sees how many references were created rather than how many are left. It frees when the decremented count is 0 or 1, so two references work and three or more leak. Sharing kept one array entry per object, and create_var_ref() searches and appends within a single trigger, so nothing outside it holds the object. Removing a trigger whose variables are still referenced is already refused by check_var_refs() with -EBUSY. Drop the count and free unconditionally. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260906124025.3550596-1-donggeunyoo.kernel@gmail.com Fixes: 8bcebc77e85f ("tracing: Fix histogram code when expression has same var as value") Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-11function_graph: Use the saved entry's size when reprinting itDonggeun Yoo
When a graph entry does not fit in the trace_seq, print_graph_entry() saves it in the iterator's fgraph_data and reprints it on the next read. The entry has already been consumed from the ring buffer by then, so the copy is all that is left of it. The copy is sized with iter->ent_size, which no longer describes the saved entry but whatever entry the iterator has moved on to. The argument count is derived from the same field, so a 72 byte entry saved and then reprinted ahead of a 48 byte return entry loses its arguments. Record the size next to the failure flag, so that the two are always set together, and restore it before reprinting. Cc: stable@vger.kernel.org Fixes: ff5c9c576e75 ("ftrace: Add support for function argument to graph tracer") Link: https://patch.msgid.link/20260906034406.1335316-1-donggeunyoo.kernel@gmail.com Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-11fgraph: Remove unused FGRAPH_MAX_INDEXDonggeun Yoo
FGRAPH_MAX_INDEX has no user, and it expands to FGRAPH_INDEX_SIZE and FGRAPH_RET_INDEX, neither of which is defined anywhere in the tree. It was added in that form by commit 91c46b0aa917 ("function_graph: Implement fgraph_reserve_data() and fgraph_retrieve_data()"), which introduced the current data word layout under new names, so anything referencing it would have failed to build ever since. Remove it. Link: https://patch.msgid.link/20260905211922.1196366-1-donggeunyoo.kernel@gmail.com Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-11tracing/user_events: Don't destroy fields when event removal failsHenry Martin
destroy_user_event() destroys the event's fields before attempting to remove the trace event call. If user_event_set_call_visible() fails, e.g. because the event is still enabled and trace_remove_event_call() returns -EBUSY, the event is left registered with an irreversibly destroyed field list. Any subsequent interaction with the event then operates on an empty field list while it is still fully visible in tracefs. Move the field destruction after the call removal, and splice the field list back onto the event when the removal fails so the event remains in a consistent state. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260904115223.2976446-1-bsdhenrymartin@gmail.com Fixes: 7f5a08c79df35 ("user_events: Add minimal support for trace_event into ftrace") Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com> Reviewed-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-06Merge tag 'trace-v7.3-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix several tracefs files that did not take the trace_array reference A trace instance can be created and destroyed in the tracefs "instances" directory via mkdir and rmdir respectively. The instance is represented by a trace_array descriptor. Most tracefs files pass the trace_array as the private data of the inode to the open/read/write functions. Since there is no locking between the time a task opens a file and the deletion of the instance (and the freeing of the trace_array), each open needs to get a reference to the trace_array and each close must remove it. An instance can't be removed if there's any reference taken on its trace_array. The open function uses trace_array_get() that takes a lock (preventing removal of instances) and iterates the list of all existing trace_arrays and if it finds a match, it takes the reference and releases the lock. If it doesn't find a match, it causes the open to return -ENODEV. There were some added files that did not take the trace_array reference on open that needed to be fixed. Sashiko also correctly pointed out that there were some files that took an address of an field or element of the trace_array which had a pointer back to the trace_array to take its reference on open. But this leaves a slight race between referencing this element to get the trace_array as the element itself could be freed. To solve this, some helper functions were created to look for trace_arrays with this field or element in the search so that the element did not have to be dereferenced before the trace_array's reference was taken. - Add a lock around ftrace_ops initialization When a ftrace_ops is first used by ftrace, some internal initialization is performed on the ops. But if multiple tasks were calling functions that did this initialization, it could race and perform doing the initialization more than once, corrupting the internal data. Add a lock in the initialization code to prevent this from happening. - Fix splice reads on mmapped buffers The logic in the ring buffer splice code for mmapped buffers is supposed to do a copy of the memory as the mapped buffers can't be given to splice. But there was an if statement within the copy code that would return a -1 if a request for a full page was done and it wasn't a partial read. This is because this logic was written before mmapped buffers existed and this case didn't make sense at the time. For mmapped buffers it makes perfect sense and by returning early can drop a lot of pages unnecessarily. - Have the persistent ring buffer validation check nr_subbufs Sashiko reported that the validation code was relying on the saved nr_subbufs to match the calculated nr_pages + 1 and if they were off, that the code could cause corruption. Sashiko is correct, and the saved nr_subbufs should be validated before assuming it is correct. - Do not allow more than one instance with the same name on cmdline If an admin were to add more than one trace instances with the same name they all would be created, but only the first one would be accessible via tracefs. This used to not be allowed but some restructuring of code has since made it possible. - Fix the race between subbuf resize and trace_pipe_raw readers If a task was reading trace_pipe_raw while another task was changing the ring buffer subbuf size, it could crash the reader. The trace_pipe_raw readers do get their own copy of the page from the buffer, but the code needs some restructuring to not have the resize of the subbuffers cause issues. - Cap the size of the mapped (static) ring buffer nr_pages The meta data used for ring buffer mapped buffers is 32 bit in size. A normal ring buffer could (in theory) have more than 4 billion pages. But this is not allowed by mapped buffers, so enforce it. * tag 'trace-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Use a macro for static buffer bits tracing: Fix comment in tracing_buffers_splice_read() ring-buffer: Prevent truncation of nr_pages / nr_subbufs ring-buffer: Cap static ring buffer nr_pages tracing: Fix subbuf resize races with trace_pipe_raw readers tracing: Fix to avoid creating trace instances with duplicate names ring-buffer: Add checking nr_subbufs to persistent ring buffer validation ring-buffer: Allow splice reads on static buffers tracing: Take trace_array reference when opening options file ftrace: Synchronize the initialization of ftrace_ops ftrace: Take trace_array reference before accessing its ftrace_ops tracing: Have show_event_filters/triggers files take trace array ref
2026-09-04treewide: refresh kmalloc_obj() conversionsKees Cook
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
2026-09-04ring-buffer: Use a macro for static buffer bitsSteven Rostedt
Instead of hard coding 30 for the number of bits used for the static buffer ids in two places, create a macro. This way if it changes in the future, it will change in all the locations that use it. Link: https://patch.msgid.link/20260904151641.17eae0aa@gandalf.local.home Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-04tracing: Fix comment in tracing_buffers_splice_read()Steven Rostedt
The comment about returning an error if the read fails on the first iteration is slightly incorrect. It makes it sound like the only reason it could fail on a later iteration is if the subbuf order changed. That is incorrect, it could also fail if the length passed in was not a multiple of the subbuf size. Fix the comment. Link: https://lore.kernel.org/all/20260904143527.40e73d36@gandalf.local.home/ Link: https://patch.msgid.link/20260904144902.506862a1@gandalf.local.home Fixes: dae8dda341d2 ("tracing: Fix subbuf resize races with trace_pipe_raw readers") Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-04ring-buffer: Prevent truncation of nr_pages / nr_subbufsVincent Donnefort
Although ring_buffer_per_cpu::nr_pages is defined as unsigned long, it is capped to 32-bits in a few places, limiting the operations possible on a very large buffer. Use `unsigned long` where appropriate and prevent truncation of values using nr_pages (or nr_subbufs). While at it, subbuf_size must be at least `unsigned int`. Note that persistent, remote and user-mapped ring buffers are capping the number of pages to 30 bits already, making "int" safe in many places. Link: https://patch.msgid.link/20260904164450.1345852-5-vdonnefort@google.com Signed-off-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-04ring-buffer: Cap static ring buffer nr_pagesVincent Donnefort
Static ring buffers (i.e. persistent, user-mapped and remote) rely on the bpage::id field. The number of pages for those ring buffers must fit into that variable. Enforce this limit on ring buffer creation or user-mapping. While at it, prevent nr_pages underflow when allocating a persistent buffer. Link: https://patch.msgid.link/20260904164450.1345852-4-vdonnefort@google.com Fixes: be68d63a139b ("ring-buffer: Add ring_buffer_alloc_range()") Signed-off-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-04tracing: Fix subbuf resize races with trace_pipe_raw readersVincent Donnefort
Concurrent subbuffer resizes may crash trace_pipe_raw readers or leak uninitialized memory to userspace due to stale size values. Modify ring_buffer_alloc_read_page() to handle the resizing of an existing buffer_data_read_page if necessary and add a new ring_buffer_read_page_size(). This new function enables ring-buffer buffer_data_read_page users to not call the racy ring_buffer_subbuf_size_get(). This makes the spare_size member of ftrace_buffer_info redundant. Finally, handle buffer_data_read_page/reader_page order discrepancy in ring_buffer_read_page(). On a mismatch simply copy manually the data to the buffer_data_read_page. Link: https://lore.kernel.org/all/20260817140812.2C7D41F00A3A@smtp.kernel.org/ Link: https://patch.msgid.link/20260904164450.1345852-3-vdonnefort@google.com Fixes: bce761d75745 ("ring-buffer: Read and write to ring buffers with custom sub buffer size") Signed-off-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-04tracing: Fix to avoid creating trace instances with duplicate namesMasami Hiramatsu (Google)
Since commit e645535a954a ("tracing: Add option to use memmapped memory for trace boot instance") changed trace_array_get_by_name() to trace_array_create_systems(), enable_instances() does not reuse the same name instance. Therefore, if an administrator mistakenly specifies multiple `trace_instance=` options with duplicate names, all are created but only the first is accessible via tracefs. Check whether an instance with the same name already exists before creating a new one, and reject duplicates with a warning. Link: https://patch.msgid.link/178847790399.283263.5313150997200138426.stgit@devnote2 Fixes: e645535a954a ("tracing: Add option to use memmapped memory for trace boot instance") Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-03ring-buffer: Add checking nr_subbufs to persistent ring buffer validationSteven Rostedt
Sashiko reported that the code was using meta->nr_subbufs without making sure that it matched the nr_pages + 1 on data that was assuming the two were the same. Add a check to the persistent ring buffer validation code to make sure that the saved nr_subbufs matches what we expect. Link: https://patch.msgid.link/20260903132728.7fb27d34@gandalf.local.home Fixes: f5b95f1fa2ef3 ("ring-buffer: Validate the persistent meta data subbuf array") Reported-by: sashiko-bot@kernel.org Closes: https://lore.kernel.org/all/20260901164836.D962D1F000E9@smtp.kernel.org/ Reviewed-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-03ring-buffer: Allow splice reads on static buffersVincent Donnefort
ring_buffer_read_page() rejects splice (full=1) reads on static buffers (that is user-mapped, persistent or remote) because !read check assumes unread pages must be swapped. However for those buffers we have no other choice than memcpy the data. For the memcpy case, only return an error when the writer is still on the reader page for the splice interface to wait. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260901155445.1475405-2-vdonnefort@google.com Fixes: 117c39200d9d ("ring-buffer: Introducing ring-buffer mapping functions") Signed-off-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-03tracing/probes: Fix use-after-free on field name/type of events with ↵Henry Martin
multiple probes The fields of a probe-based dynamic event (kprobe, uprobe, eprobe and fprobe events) are created in traceprobe_define_arg_fields() by handing the probe_arg name/type strings to trace_define_field(), which only stores the pointers without copying. Those strings are owned by the trace_probe and are freed when that probe is removed. An event can have several probes attached. The field list is defined only once, by the first probe that registers the event, but it is kept alive by any surviving sibling probe. Deleting just that first probe by symbol - # primary A: fields are defined from A's args echo 'p:kprobes/ev vfs_read a1=$arg1' > kprobe_events # append B: shares A's event call echo 'p:kprobes/ev vfs_write a1=$arg1' >> kprobe_events # delete only A (matched by symbol), B survives echo '-:kprobes/ev vfs_read' >> kprobe_events frees A's args (trace_probe_cleanup() -> traceprobe_free_probe_arg()), but trace_probe_unlink() keeps the trace_probe_event because the probe list is not empty. The event call stays registered via B while its fields now reference freed memory. Any field lookup then reads it, e.g. echo 'a1 == 1' > events/kprobes/ev/filter BUG: KASAN: slab-use-after-free in strcmp+0xa7/0xb0 Call Trace: strcmp trace_find_event_field parse_pred process_preds create_filter apply_event_filter event_filter_write field->name references parg->name (kstrdup'd, freed with the probe) and, for array arguments, field->type references parg->fmt (kmalloc'd, freed with the probe) - the scalar type otherwise points at the static fmttype rodata, which is safe. Have traceprobe_define_arg_fields() duplicate the name and type strings and anchor the copies on the trace_probe_event, which embeds the event call and outlives every individual probe; trace_probe_event_free() releases them. The reproducer above triggers reliably; the field lookup and the delete both run under event_mutex, so this is a dangling reference after removal rather than a race. The issue was found by the autokbug dynamic kernel fuzzer at Tencent Yunding Lab. Link: https://lore.kernel.org/all/20260826030009.1855331-1-bsdhenrymartin@gmail.com/ Fixes: ca89bc071d5e4 ("tracing/kprobe: Add multi-probe per event support") Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-09-03tracing/probes: Fix code indent in get_bitoffset_of_field()Masami Hiramatsu (Google)
Fix code block indentation introduced by commit f21834524025 ("tracing/probes: Support field specifier option for typecast"). Link: https://lore.kernel.org/all/178827252027.123716.7095571176291547259.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-03tracing/probes: Fix BTF kflag check for anonymous struct member accessMasami Hiramatsu (Google)
btf_find_struct_member() traverses into nested anonymous structures and unions to find a struct member. However, get_bitoffset_of_field() in trace_probe.c checked btf_type_kflag(type) using the outer parent type instead of the actual anonymous structure/union that directly contains the found member. If the parent structure and anonymous structure have mismatched kflags (e.g., the parent has kflag=0 while the anonymous structure has kflag=1 because it contains bitfields), the bitfield size encoded in the upper 8 bits of member->offset is erroneously treated as part of the byte/bit offset, corrupting the resolved offset and failing to set last_bitsize. Similarly, btf_find_struct_member() pushed anonymous member offsets onto anon_stack without masking BTF_MEMBER_BIT_OFFSET() when kflag is set. To fix this problem, update btf_find_struct_member() to return actual containing structure/union type via member_type, use appropriate __btf_member_bit_offset() to get bit offset, and use member_type for btf_type_kflag() in get_bitoffset_of_field(). Link: https://lore.kernel.org/all/178827250904.123716.17452648791331881284.stgit@devnote2/ Fixes: c440adfbe302 ("tracing/probes: Support BTF based data structure field access") Cc: stable@vger.kernel.org Reported-by: Sashiko <sashiko-bot@kernel.org> Closes: https://lore.kernel.org/all/20260822095110.0772E1F000E9@smtp.kernel.org/ Assisted-by: Antigravity:gemini-3.7-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-03tracing/probes: Fix anon_stack check for unnamed bitfields in ↵Masami Hiramatsu (Google)
btf_find_struct_member btf_find_struct_member() traverses into nested anonymous structures and unions by pushing members with !member->name_off onto anon_stack. However, it does not consider the unnamed bitfields (e.g. `int : 5` or `unsigned int : 0`) which also have member->name_off == 0. If such an unnamed bitfield is pushed to anon_stack, the btf_find_struct_member() return an error even if there are other valid entries in anon_stack. To fix this, only push unnamed struct/union members to anon_stack. Also move the btf_type_is_struct() check to the entry of this function because now it is sure only struct/union are pushed to anon_stack. Link: https://lore.kernel.org/all/178827249775.123716.7813217688423513612.stgit@devnote2/ Fixes: 302db0f5b3d8 ("tracing/probes: Add a function to search a member of a struct/union") Cc: stable@vger.kernel.org Reported-by: Sashiko <sashiko-bot@kernel.org> Closes: https://lore.kernel.org/all/20260830143859.D56991F00A3D@smtp.kernel.org/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-02tracing: Take trace_array reference when opening options fileSteven Rostedt
The options files do not take the trace_array reference for the options they represent. This could cause a use-after-free kernel crash if one of these files is opened by one task and another task removes the instance that the option is for. Because it doesn't take a reference upon opening, it will not stop the removal which will free the options descriptor that is being used. As the options are somewhat dynamic in their creation at boot up, each file represents a flag in the trace_array. The trace_array has an array of indexes to represent each of these flags that is stored in the trace_flags_index array. The address of the index array element is used to pass to the inode->i_private pointer. Then that element is read which holds the index (which represents the flag) and then the index is used to calculate the trace_array descriptor from its trace_flags_index array. One issue is that the index element can not be referenced until the trace_array's reference is taken. To handle this, create a new helper function called: trace_array_options_get() that will iterate all the existing trace_arrays in the ftrace_trace_arrays list (under the trace_types_lock), and compare the passed in address of the index element with the entire array of the trace_array's trace_flags_index array. If it matches, then up the corresponding trace_array's reference and return. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902121918.5a9e9d1b@gandalf.local.home Fixes: 577b785f55168 ("tracing: add tracer dependent options to options directory") Reported-by: sashiko-bot@kernel.org Closes: https://lore.kernel.org/linux-trace-kernel/20260828135858.2AC501F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-02ftrace: Synchronize the initialization of ftrace_opsSteven Rostedt
There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-01ftrace: Take trace_array reference before accessing its ftrace_opsSteven Rostedt
The trace instance files set_ftrace_filter and set_ftrace_notrace was updated to work with specific trace instances (trace_arrays). The issue is that when these files are opened, there is a small race window where it will use the ftrace_ops from the inode->private pointer to get a reference to the trace_array and then take its reference. The problem is that the ftrace_ops itself could be freed. If the rmdir on the instance happens at the same time the set_ftrace_filter file is opened, the rmdir could have also freed the ftrace_ops and referencing it will cause a use-after-free bug and crash the kernel. Instead, pass in the trace_array as the file private data (NULL for the top level instance), and then pass both the trace_array and the ftrace_ops to the ftrace_regex_open() function. If the trace_array is NULL, then it just uses the ftrace_ops without the need to take its reference (like normal). If the ftrace_ops is NULL, that is only the case for the top level instance and the global_ops can be used. This allows the trace_array to have its reference incremented before touching the ftrace_ops that could also be freed when the instance is. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260828223901.29e26edb@robin Fixes: 591dffdade9f0 ("ftrace: Allow for function tracing instance to filter functions") Reported-by: Breno Leitao <leitao@debian.org> Tested-by: Breno Leitao <leitao@debian.org> Closes: https://lore.kernel.org/all/apGORjltZgAiAYHT@gmail.com/ Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-01tracing: Have show_event_filters/triggers files take trace array refSteven Rostedt
The newly added files show_event_filters and show_event_triggers that show all filters or triggers that are set within the trace array do not take a reference for the trace array it is showing. Without taking a reference, the trace_array may be freed via "rmdir" while a task is reading one of theses files. Those files iterate all the events within an instance (trace_array) and nothing prevents that instance from being freed while its data is being read. This causes a use-after-free crash. Have the open of both those files take the trace_array reference via the trace_array_get() that prevents the trace_array from being freed while the files are opened. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260828094153.17b95037@gandalf.local.home Fixes: 729757b96a662 ("tracing: Add show_event_filters to expose active event filters") Fixes: 6a80838814eea ("tracing: Add show_event_triggers to expose active event triggers") Reported-by: Farhad Alemi <farhad.alemi@berkeley.edu> Closes: https://lore.kernel.org/all/CA+0ovCjerKZJLwXScM9bF2ga2rLi4_XOpUfK41NDbENpeu98jA@mail.gmail.com/ Reviewed-by: Aaron Tomlin <atomlin@atomlin.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-01uprobes: guard trace cleanup against error pointersAndi Kleen
Sashiko pointed out the some of the scope cleanups for free_uprobe could get an error pointer. Handle this case in free_uprobe to prevent a crash. On the other hand the macro doesn't need the guard because free_uprobe itself already does the check. Link: https://lore.kernel.org/all/20260831150651.1134594-2-ak@kernel.org/ Assisted-by: omp:gpt-5.6-luna sashiko Signed-off-by: Andi Kleen <ak@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-08-30Merge tag 'trace-v7.3-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure
2026-08-27ring-buffer: Stop remote reader update when page swap failsIvan Immanuel Shaji
The remote swap_reader_page callback can return -EBUSY when the writer moves the head before the remote catches it, particularly during an event storm on a small buffer. __rb_get_reader_page_from_remote() currently warns about that failure but continues with the unchanged reader ID and rearranges the local page list as though the swap succeeded. Handle the callback failure as a recoverable error. Report it with pr_warn_ratelimited() and return NULL. Callers already handle a NULL reader page as a failed attempt. This avoids splicing the same page as both the previous and new reader without flooding the log under contention. Cc: stable@vger.kernel.org Fixes: 2e67fabd8b77 ("ring-buffer: Introduce ring-buffer remotes") Link: https://patch.msgid.link/20260825-kernel-patch-1-v2-2-bb3461807a32@gmail.com Assisted-by: LLM sparse Signed-off-by: Ivan Immanuel Shaji <ivanimmanuel1234@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-27tracing: Fix retry exhaustion in simple ring buffer reader swapIvan Immanuel Shaji
simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. The current !retry test reverses both outcomes. It returns an error after a successful final replacement, leaving the link update complete but the reader bookkeeping unfinished. After a failed final replacement, it falls through and updates the head and reader pointers as though the replacement succeeded, which can corrupt the ring. Treat only a negative counter as exhaustion and return the documented -EBUSY error. Cc: stable@vger.kernel.org Fixes: 34e5b958bdad ("tracing: Introduce simple_ring_buffer") Link: https://patch.msgid.link/20260825-kernel-patch-1-v2-1-bb3461807a32@gmail.com Assisted-by: LLM sparse Reviewed-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Ivan Immanuel Shaji <ivanimmanuel1234@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-27tracing/user_events: Clear copied tracing state before fork duplicationJérémy Jean
dup_task_struct() copies user_event_mm from the parent into the child, without grabbing a reference to it. user_event_mm_dup() should replace it, but it leaves that copied pointer unmodified if user_event_mm_alloc() fails. When the child exits, user_event_mm_remove() decrements a reference the child never owned, which ultimately frees user_event_mm, while the parent still as a stale pointer to it. This creates a UAF, which KASAN reports as: BUG: KASAN: slab-use-after-free in current_user_event_mm+0x51/0x1d0 Write of size 4 at addr ffff888005010d30 by task init/44 Call Trace: <TASK> kasan_report+0xce/0x100 kasan_check_range+0x10f/0x1e0 current_user_event_mm+0x51/0x1d0 user_events_ioctl+0x82e/0x15c0 __x64_sys_ioctl+0x139/0x1c0 do_syscall_64+0xce/0x450 entry_SYSCALL_64_after_hwframe+0x77/0x7f Allocated by task 44: __kasan_kmalloc+0x8f/0xa0 __kmalloc_cache_noprof+0x180/0x3a0 user_event_mm_alloc+0x3c/0x1f0 current_user_event_mm+0x88/0x1d0 Freed by task 42: __kasan_slab_free+0x43/0x70 kfree+0x13a/0x390 process_one_work+0x696/0xf90 worker_thread+0x420/0xba0 The fix simply clears the copied pointer before any possible failure. In case of failure, the child then has nothing to free. Cc: stable@vger.kernel.org Fixes: 7235759084a4 ("tracing/user_events: Use remote writes for event enablement") Link: https://patch.msgid.link/20260827184321.2964601-2-Jeremy.Jean@oss.cyber.gouv.fr Assisted-by: Codex:gpt-5 Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr> Reviewed-by: Bradley Morgan <brads@mainlining.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-22tracing: Fix use-after-free in trace_pipe read on sub-buffer order changeDeepanshu Kartikey
Writing to buffer_subbuf_size_kb calls ring_buffer_subbuf_order_set(), which frees every sub-buffer of the ring buffer, including the reader page, and replaces them with newly allocated ones. Readers of trace_pipe hold pointers into those pages. ring_buffer_peek() looks up an event under cpu_buffer->reader_lock but returns the event pointer after dropping the lock, and peek_next_entry() then calls ring_buffer_event_length() and ring_buffer_event_data() on it. If the sub-buffer order is changed in that window, the reader dereferences freed memory: BUG: KASAN: use-after-free in ring_buffer_peek+0x3e0/0x430 Read of size 1 at addr ffff88802a4cf010 by task syz-executor989/6002 Freed by: free_buffer_page kernel/trace/ring_buffer.c:398 [inline] ring_buffer_subbuf_order_set+0x1325/0x18e0 kernel/trace/ring_buffer.c:7444 buffer_subbuf_size_write+0x182/0x280 kernel/trace/trace.c:8221 Take trace_access_lock(RING_BUFFER_ALL_CPUS) around the order change. This is the lock trace_pipe readers already hold across their entire peek-and-print loop, so the swap can no longer race with a reader that is dereferencing a peeked event. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260817140655.5694-1-kartikey406@gmail.com Fixes: f9b94daa542a ("ring-buffer: Set new size of the ring buffer sub page") Reported-by: syzbot+685955db58555575fdd2@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=685955db58555575fdd2 Tested-by: syzbot+685955db58555575fdd2@syzkaller.appspotmail.com Reviewed-by: Bradley Morgan <include@grrlz.net> Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-22tracing: Fix crash passing ERR_PTR to kthread_stop()Hui Su
event_test_stuff() calls kthread_run() and unconditionally passes the returned task_struct pointer to kthread_stop(). kthread_run() returns an error pointer such as ERR_PTR(-ENOMEM) when kthread creation fails, for example under memory pressure during the boot-time event self-test. kthread_stop() then dereferences the invalid pointer, crashing the kernel. Check the result of kthread_run() before passing it to kthread_stop(). Use WARN_ON() so that a failure to create the self-test thread does not go unnoticed, matching the ring-buffer self-test fix in commit 91542863abad ("ring-buffer: Fix crash passing ERR_PTR to kthread_stop()"). Cc: stable@vger.kernel.org Fixes: e6187007d6c3 ("tracing/events: add startup tests for events") Link: https://patch.msgid.link/20260817120642.668375-3-sh_def@163.com Signed-off-by: Hui Su <sh_def@163.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-22tracing: Fix use-after-free with same-name named triggersHui Su
When two hist triggers on different events are registered with the same name=, the second one reuses the first as named_data. Both are added to tr->hist_vars by save_hist_vars() during event_hist_trigger_parse(), because save_hist_vars() is called before event_trigger_register() while the named reuse is only detected later, in hist_register_trigger(). In the named-data branch hist_register_trigger() then frees the second histogram's hist_data via destroy_hist_data(), but never removes its tr->hist_vars list entry, leaving a dangling pointer and leaking the trace_array reference it holds. A later hist trigger that references a variable makes find_var_file() walk tr->hist_vars and dereference the freed hist_data. The bug is reproducible from userspace by writing three hist triggers to tracefs: cd /sys/kernel/tracing echo 'hist:keys=common_pid:x=common_pid:name=mh' > events/sched/sched_switch/trigger echo 'hist:keys=common_pid:x=common_pid:name=mh' > events/sched/sched_process_fork/trigger echo 'hist:keys=common_pid:vals=$x' > events/sched/sched_process_exit/trigger The third write panics the kernel: BUG: KASAN: slab-use-after-free in find_var_file.part.0+0x272/0x290 Read of size 8 at addr ffff888001f8a0e0 by task sh/1 CPU: 1 UID: 0 PID: 1 Comm: sh Tainted: G D N Call Trace: find_var_file.part.0 find_event_var parse_atom parse_expr __create_val_field event_hist_trigger_parse trigger_process_regex event_trigger_write vfs_write ksys_write do_syscall_64 entry_SYSCALL_64_after_hwframe Allocated by task 1: event_hist_trigger_parse Freed by task 1: hist_register_trigger+0x618/0xa30 event_hist_trigger_parse The buggy address belongs to freed 2048-byte region Oops: general protection fault ... RIP: find_var_file.part.0 Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b Fix by removing the hist_data from tr->hist_vars and releasing the trace_array reference in the named-data branch of hist_register_trigger() before freeing the hist_data. Cc: stable@vger.kernel.org Fixes: 6f86bdeab633 ("tracing: Fix bad hist from corrupting named_triggers list") Link: https://patch.msgid.link/20260816100427.33642-3-sh_def@163.com Signed-off-by: Hui Su <sh_def@163.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-22tracing: Fix logged instance name on creation failureVincent Donnefort
When boot instance creation fails, the kernel incorrectly logs "(null)" as the instance name because strsep() consumes curr_str entirely during parsing. Print the properly parsed name variable instead. And while at it log the error code. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260807085423.4175161-1-vdonnefort@google.com Fixes: cb1f98c5e574 ("tracing: Add creation of instances at boot command line") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-20Merge tag 'mm-stable-2026-08-18-18-39' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "mm: drop "sub" prefix from various places" (Dev Jain) page->folio conversion and a naming cleanup - "mm/kasan: remove redundant initialization for kasan_flag_write_only" (Igor Putko) KASAN cleanup work - "mm/filemap: reduce unnecessary xarray lookups" (Chi Zhiling) Small speedup in the pagecaache read code - "mm/percpu: Fix possible NOFS/NOIO reclaim recursion" (Kaitao Cheng) Improve the vmalloc code - mainly the avoidance of GFP_KERNEL allocations when the caller asked for GFP_NOFS or GFP_NOIO - "mm/kmemleak: avoid soft lockup when scanning task stacks" (Breno Leitao) Avoid a soft lockup watchdog trigger from the kmemleak scanning code in extreme situations - "mm/page_owner: misc cleanups" (Ye Liu) Cleanups to the page_owner code. For some reason lots of people have been working on the page_owner code this cycle. - "mm: convert to walk_page_range_vma() to eliminate find_vma()" (Kefeng Wang) Simplify and accelerate the page walking library function - "mm/migrate: preparatory cleanups for batch copy and offload" (Shivank Garg) Cleanups in the migration code - "mm/page_owner: add per-fd filter infrastructure for print_mode and NUMA filtering" (Zhen Ni) Per-fd filtering to page_owner in order to reduce the sometimes vast amount of output it can produce - "mm: Refactor bootmem gigantic hugepage allocation" (Muchun Song) Fixes and preparatory cleanups around bootmem HugeTLB handling, sparse initialization ordering, and related vmemmap setup - "mm/zsmalloc: reduce lock contention in zs_free()" (Wenchao Hao) Reduce lock contention in zs_free(), which dominates the unmap path under memory pressure on Android (LMK kills) and on x86 servers running zswap-heavy workloads. Up to 1.83x improvement in microbenchmarking. - "move alloc_tag.c file under mm/" (Suren Baghdasaryan) - "samples/damon: handle damon_{start,stop}() failures" (SJ Park) Fix improper handling of damon_start(), damon_stop(), and damon_call() failures across DAMON sample modules to prevent potential memory leaks, operation disruptions and use-after-free bugs - "mm/damon/sysfs: kobject_del() directories that users can create/remove" (SJ Park) Fix delayed sysfs directory removal under DEBUG_KOBJECT_RELEASE causeing creation failures due to duplicate directory names by adding missing kobject_del() calls before creating new directories - "mm: cleanup clear_not_present_full_ptes()" (David Hildenbrand) Clean up the core pte handling code - "selftests/damon: misc fixes for test bugs" (Kunwu Chan) Fix several bugs in the DAMON selftests - "selftests/damon: fix memcg_path staging handling" (Cheng Nie) Fix a bug in _damon_sysfs.py for damos_filter memcg_path setup, and add a test case for it in sysfs.py. - "selftests/damon: test kdamond refresh_ms" (Ruslan Valiyev) Selftest coverage for DAMON's refresh_ms sysfs feature by updating the test control module and verifying that scheme stats update automatically without manual intervention - "mm/damon: five misc fixups" (Akinobu Mita) Miscellaneous DAMON fixups. - "mm/damon/core: detect internal variation above max_nr_regions/2" (Jiayuan Chen) Fix DAMON's region splitting behavior when region counts exceed half the maximum budget by dynamically scaling down the split fraction as the limit approaches, preventing large regions from staying un-split, and add corresponding KUnit test coverage - "mm: preparatory patches for PMD level swap entries" (Usama Arif) Refactor and clean up PMD softleaf helpers, call sites, and architecture flags to lay the groundwork for a follow-up series that introduces PMD page table swap entries - "mm/damon: update, optimize, and clean up doc, tests, and code" (SJ Park) Update DAMON design and ABI documentation, expands unit and selftest coverage, optimize damon_commit_target_regions(), and clean up recently added sysfs interface code for better readability - "mm/vmpressure: reduce CPU, memory and code overhead on cgroup v2" (Usama Arif) Optimize vmpressure() by skipping unnecessary work on cgroup v2 for userspace event notifications and refactor v1-only eventfd handling into mm/memcontrol-v1.c to reduce memory overhead and code complexity - "selftests/mm: refactor pkey helpers and fix mmap error handling" (Hongfu Li) Refactor pkeys shared tracing and assertion helpers into a common file, unify protection key selftests to use consistent diagnostic logging and assertions, and enforce standardized MAP_FAILED return checks for mmap() calls across the tests - "mm/damon: optimize out nr_accesses_bp" (SJ Park) Replace the error-prone, continuously updated nr_accesses_bp field in damon_region with an on-demand moving sum function, reducing structure memory overhead and avoiding state corruption bugs - "Open HugeTLB allocation routine for more generic use" (Ackerley Tng) Decouple HugeTLB folio allocation from VMA dependencies by introducing hugetlb_alloc_folio(), enabling subsystems like guest_memfd to allocate HugeTLB folios without standard VMA reservations or pseudo-VMAs - "mm/damon: provide pseudo moving sum probe_hits" (SJ Park) Integrate DAMON's probe_hits attribute counter into the pseudo moving sum infrastructure, enabling real-time, online monitoring without waiting for full aggregation intervals - "mm: Some cleanups for page allocator APIs" (Brendan Jackman) Simplify and refactor the page allocator entry points and flags by unifying allocation paths, adding internal alloc_flags arguments, and eliminating redundant __ prefixed alloc_pages variants. - "Fix incorrect access of hugetlb pte entries" (Dev Jain) Enforce the consistent use of huge_ptep_get() instead of ptep_get() for HugeTLB entries and fixes an unaligned address issue in arm64's huge_ptep_get() implementation - "mm/damon: validate all parameters in the core" (SJ Park) Consolidate parameter validation into the DAMON core specifically within damon_start() and damon_commit_ctx() to centralize error checking, eliminate caller-side redundant checks and to improve maintenance efficiency - "tools/mm/page_owner_sort: fix filtering and cleanup issues" (Yichong Chen) Rename is_need() to filter_record() for clearer return semantics, fix per-record allocation memory leaks and bound output copies in search_pattern() to address an existing buffer issue - "memcg: bail out reclaim when memcg is dying" (Jiayuan Chen) Mitigate a system-wide stall which occurs when a cgroup is removed while one of its memory control files is doing synchronous reclaim - "mm/memory-failure: add panic option for unrecoverable pages" (Breno Leitao) Introduce an opt-in vm.panic_on_unrecoverable_memory_failure sysctl that immediately panics the kernel on unrecoverable memory errors in kernel-owned pages to preserve error context and prevent delayed, silent data corruption - "mm/damon: refactor damon_{start,stop,commit}() for simple error handling" (SJ Park) Refactor the DAMON core API functions to guarantee that all contexts are fully stopped when damon_start(), damon_stop(), or damon_commit() fail, eliminating the need for complex and error-prone caller-side cleanup code - "Keep tail page private zero at free and folio split" (Zi Yan) Add checks to ensure tail_page->private is zero when freeing compound or high-order pages and when promoting tail pages during large folio splits. By validating these fields at free and split time, it allows the removal of redundant private field clearing inside prep_compound_tail() - "mm: drop redundant lru_add_drain in anon folio reuse paths" (Barry Song) Eliminate redundant lru_add_drain() calls in wp_can_reuse_anon_folio() and do_swap_page() to reduce LRU lock contention and system overhead By validating folio refcounts against the LRU cache before draining and removing unnecessary drains in the swap path, it achieves up to a 30.5% reduction in drain calls during heavy swap workloads - "mm: clean up folio LRU and swap declarations" (Jianyue Wu) Reorganize folio LRU and swap code by relocating page-cluster state to mm/swap_state.c, renaming mm/swap.c to mm/folio.c, and moving MM-internal reclaim declarations into mm/internal.h. - "userfaultfd: working set tracking for VM guest memory" (Kiryl Shutsemau) Add userfaultfd support for tracking the working set of VM guest memory, so a VMM can identify hot pages and reclaim cold ones to tiered or remote storage - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 2)" (David Hildenbrand) Remove the remaining pieces of CONFIG_HAVE_BOOTMEM_INFO_NODE, performing some smaller cleanups around freeing of reserved vmemmap pages on the way. - "mm/damon: update probe hits for runtime parameter commits" (SJ Park) Ensure that DAMON's probe_hits attribute counter is properly updated when monitoring intervals are changed at runtime, matching the behavior of nr_accesses. To achieve this, it refactors and renames existing helper functions for shared use, applies the updates to probe_hits, and handles edge cases in damon_probe_hits_mvsum() to maintain measurement accuracy. - "KSM: performance optimizations for rmap_walk_ksm" (xu xin) Resolve a severe KSM reverse-mapping performance bottleneck where thousands of split VMAs sharing a single anon_vma cause extended lock contention. By adding an interval-filtering check during the rmap walk, it reduces worst-case anon_vma lock hold times from over 500ms down to under 2ms, preventing application freezes and latency spikes under memory pressure. - "mm: split a couple of headers from internal.h" (Mike Rapoport) Split declarations related to mm_init, memblock, vmalloc and sparse into new headers - "KSM: use linear_page_index in collect_procs_ksm()" (xu xin) Apply the interval tree optimization from rmap_walk_ksm() to collect_procs_ksm() to avoid iterating over non-matching VMAs during KSM memory error handling. It hoists loop-invariant address initialization and restricts the anon_vma_interval_tree_foreach walk to a targeted page offset range, reducing redundant checks and improving lookup efficiency. - "selftests/mm: avoid false failures in hugetlb and KSM tests" (Sayali Patil) Fix issues in the hugetlb and KSM MM selftest categories that can report failures when the prerequisites for the tests are not satisfied - "mm/damon: introduce data attributes only monitoring" (SJ Park) Introduce attribute-weighted region management in DAMON, allowing users to prioritize specific data attributes (such as page sizes or cgroups) over or instead of access monitoring. By assigning weights to attribute probes, DAMON can completely disable access tracking and adjust monitoring regions based on weighted probe-hit counters to optimize monitoring quality for attribute-focused workloads. - "mm/hmm: Add mmap lock-drop support for userfaultfd-backed mappings" (Stanislav Kinsburskii) Extend hmm_range_fault() to support userfaultfd-backed regions by allowing the mmap lock to be dropped during fault handling via a new hmm_range_fault_locked() helper. By accepting a locked pointer and signaling retry status when lock release occurs, it enables page fault resolution in userfaultfd regions while preserving backward compatibility for existing callers. - "mm: make VMA page offset handling more consistent" (Lorenzo Stoakes) Clean up and standardize how vma->vm_pgoff is accessed and manipulated across file-backed and anonymous mappings in the kernel It introduces dedicated helper functions such as vma_start_pgoff(), vma_end_pgoff(), vma_set_pgoff() and linear_page_delta() while renaming rmap interval tree helpers to better reflect their functionality. These changes establish a cleaner foundation for future work that will unify virtual page offset indexing for all anonymous and CoW'd folios. - "mm: handle device-private PMDs in walk callbacks" (Usama Arif) Address kernel panics and state corruption caused by MM walk callbacks reaching non-present device-private PMD swap entries created during HMM migrations It ensures that functions which acquire pmd_trans_huge_lock() properly recognize device-private PMDs instead of assuming a present THP or a standard migration entry. - "mm/rmap: Refactor try_to_unmap_one" (Dev Jain) Refactor try_to_unmap_one by modularizing Hugetlb, anonymous-lazyfree, and anonymous-swapbacked logic into dedicated functions, laying the structural groundwork for batched anonymous large folio unmapping. - "Docs/ABI/damon: sysfs ABI document fixes and additions" (Song Hu) Fix typos and fills in missing entries in the DAMON sysfs ABI document - "dax/kmem: atomic whole-device hotplug via sysfs" (Gregory Price) Introduce an atomic sysfs state attribute and supporting DAX/MM infrastructure to prevent userland races when offlining and removing entire memory regions By adding an unplugged state alongside standard online modes, it enables whole-device atomic hotplug control while preserving backward compatibility. - "mm: convert more vm_flags_t users to vma_flags_t" (Lorenzo Stoakes) Continue transitioning the kernel from the deprecated vm_flags_t type to vma_flags_t across core memory management infrastructure. It replaces legacy type usage in core functions such as do_mmap(), unmapped area allocation, mm->def_vma_flags, and VMA operations like mlock, mprotect, and mremap. - "Two small patches to clean up mm/mm_slot.h" (xu xin) Refactor mm_slot.h by introducing mm_slot_remove() to unify duplicate slot deletion sequences in khugepaged and KSM. It also adds code documentation explaining why mm_slot_lookup and mm_slot_insert must remain as preprocessor macros rather than static inline functions. - "mm/damon/core: hide core-private struct fields" (SJ Park) Clean up DAMON core structures by consistently marking internal-only fields with private: comment tags to prevent improper direct access from outer layers. It enforces encapsulation across core structures including damon_region, damon_target, and damon_ctx and updates DAMON_SYSFS to interact through approved access APIs instead of exposing raw struct members. - "mm/damon: unurgent fixes for infinite loop, NULL de-ref and races" (SJ Park) Address potential infinite loops, NULL dereferences, and race conditions identified in DAMON It fixes an infinite loop triggered by extreme user configurations, a NULL pointer dereference within unit tests and minor monitoring accuracy degradation caused by subtle runtime races. - "mm/page_alloc: fixes for free_pages_nolock() on RT/UP" (Brendan Jackman) Fix an NMI safety flaw in __free_frozen_pages() where freeing pages on non-SMP or PREEMPT_RT kernels can bypass can_spin_trylock() checks via non-PCP or isolated migration paths. It also resolves potential kernel crashes and privilege escalation risks triggered when BPF tracing runs in NMI context alongside memory hotplug or large allocation frees. - "mm/page_alloc: couple of followups for recent cleanups" (Brendan Jackman) Clean up and update page allocator nomenclature, documentation, and debug assertions. It aligns internal FPI_ flags with the public "nolock" naming convention, removes outdated internal implementation details from high-level page allocator comments, and eliminates obsolete VM_BUG_ON() assertions in allocation paths. - "mm/mseal: further cleanups" (Lorenzo Stoakes) Refactor and simplify the mseal implementation by clarifying API boundaries and removing unnecessary code complexity. It replaces generic do_mseal() usage outside the syscall with a dedicated mseal_mmap_page_zero() helper for MMAP_PAGE_ZERO, eliminates mm_struct parameters to enforce that sealing applies only to current->mm, and streamlines overall logic and comments with no functional changes intended. - "mm/vmscan: fix swappiness=max and clean up per-node proactive reclaim" (Ridong Chen) Resolve reclaim behavior bugs and clean up function parameters across memory reclaim paths It fixes swappiness=max in both standard reclaim and MGLRU so unswappable anonymous memory no longer falls back to evicting page cache, ensures reclaim_store() returns accurate error codes instead of collapsing all failures into -EAGAIN, and removes the obsolete gfp_mask parameter from __node_reclaim(). - "mm: mincore: misc cleanups" (Kefeng Wang) Clean up and simplifies the mincore code. Most importantly, it removes the historical special behavior that always reports VM_PFNMAP pages as non-resident. - "mm/huge_memory: drop dead split helper variants" (Kiryl Shutsemau) Two trivial cleanups in the folio split API - "mm/damon: fix uninitialized DAMOS field and kunit exec expectation bugs" (SJ Park) Resolve minor operational and testing bugs in DAMON identified by Sashiko. It initializes the damos->last_applied field to prevent occasional efficiency degradation and fixes invalid memory accesses in DAMON KUnit tests during test failure handling. - "cleanup for stable_page_flags()" (Jinjiang Tu) Clean up and refactor stable_page_flags() used by /proc/kpageflags without altering functionality. It uses BIT_ULL() to prevent shift-overflow warnings on 64-bit flag bits, converts folio-specific flag checks to standard folio_test_*() helpers, and removes redundant CONFIG_PAGE_IDLE_FLAG handling. - "Batch unmap of uffd-wp file folios" (Dev Jain) Extend batched folio unmapping support to file folios within userfaultfd write-protect (uffd-wp) VMAs by adding batching capabilities to pte_install_uffd_wp_if_needed(). This removes special-case restrictions on uffd-wp VMAs in try_to_unmap_one(), significantly simplifying the function's control flow and complexity. - "mm/early_ioremap: clarify and clean up early_ioremap_reset()" (Sang-Heon Jeon) Clarify and clean up the architecture-specific usage of __late_set_fixmap() and __late_clear_fixmap() after early_ioremap_reset() It adds explicit documentation regarding when early_ioremap_reset() must be called and removes redundant macro definitions and reset calls in the RISC-V and ARM64 architectures. - "mm: fix reclaim storms in defrag_mode" (Johannes Weiner) Address severe performance regressions, swap storms, and spurious OOMs caused by vm.defrag_mode=1 under high memory pressure in Meta production It updates the page allocator slowpath so non-movable allocation requests actively trigger direct reclaim and direct compaction at pageblock_order scale, allowing them to claim whole pageblocks rather than spinning unproductively. - "zram: lockmap tweaks" (Sebastian Siewior) Optimize and fix lockdep tracking for zram devices by consolidating per-entry lockmaps and isolate lock classes across multiple instances This reduces memory overhead by replacing per-entry lockdep_map instances with a single map per struct zram, and assigns a dynamic lock_class_key to each instance to prevent false deadlock reports when different zram devices are backed by distinct filesystems. * tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (501 commits) selftests/mm: thuge-gen: fix test_shmget() for PAGE_SIZE check selftests/mm: unpoison pages in memory-failure teardown mm/shmem: downgrade final i_blocks check in shmem_evict_inode() to pr_warn() mm/khugepaged: replace mutex_lock/mutex_unlock usage with guard macro mm/zsmalloc: fix release order of locks in zs_page_migrate() Documentation: zram: remove sections numbering ksm: stop iterating VMAs when ksm_test_exit returns true mm: fold userfaultfd_rwp() to false without CONFIG_ARCH_HAS_PTE_PROTNONE mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch() zram: use a custom key for each zram object zram: move lockmap to be per-zram instead per table selftests/mm: fix gup_longterm EINVAL error message mm: page_alloc: fix non-movable reclaim storm in defrag_mode mm: page_alloc: move capture_control to the page allocator mm: compaction: support non-movable compaction for pageblock requests mm: page_alloc: __GFP_FS lockdep annotation for direct compaction hugetlb: evaluate subpool free state while locked mm/damon: remove trailing semicolons after function definitions mm/damon/ops-common: prevent migration fallback to non-target nodes mm/damon: update outdated comment about DAMOS filter handling ...
2026-08-20Merge tag 'probes-v7.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes updates from Masami Hiramatsu: "BTF typecasting and variable fetch enhancements: - Typecast support across probe events: Extended BTF typecasting syntax (e.g., (STRUCT)PARAM->MEMBER) to kprobes, uprobes, and fprobes on function entry and return - Nested typecasts: Added support for chaining and nesting typecasts up to 3 levels, including casting registers and stack variables - Field specifier option: Added (STRUCT,FIELD) syntax to emulate container_of(), allowing retrieval of parent structures from member pointers - $current variable support: Introduced $current special variable to access the running task_struct via BTF dereferencing - Per-CPU variable access: Added this_cpu_read() and this_cpu_ptr() fetcharg methods to trace CPU-local data safely - Fetcharg bytecode dumper: Added CONFIG_PROBE_EVENTS_DUMP_FETCHARG to dump the compiled fetcharg bytecode instructions as comments in dynamic_events - Extended symbol name handling: Removed the MAX_COMMON_HEAD_LEN limit and extended MAX_ARGSTR_LEN to 256 bytes, enabling probing of long symbols, mangled Rust symbols and complex BTF expressions - eprobe variable syntax: Allowed eprobes to reference event fields directly without requiring a '$' prefix - Cleanup unused parameters, redundant codes, duplicate macros and pointer arithmetic - Use a ternary operator for simplifying fetch_type_from_btf_type() Expanded boot time dynamic probe support: - Add boot-time tracing configuration support for event probes (eprobes), function probes (fprobes), and tracepoint probes (tprobes) - Allow comment lines ('#') in dynamic_events file Optimization, robustness, and cleanups: - Simplify fprobe_remove_ips() by reusing graph and ftrace helpers - Remove __packed attribute from struct __fprobe_header to avoid unaligned memory access penalties on RISC architectures - Remove redundant memset() calls in perf event probe handlers - Replace legacy __ASSEMBLY__ with __ASSEMBLER__ in header files Selftests & refactoring: - Refactor parse_probe_arg() and parse_probe_vars(), and eliminate recursion in probe argument parsing to protect kernel stack depth - Add selftests for BTF typecasts and module probing without module prefixes - Force LC_ALL=C in ftracetest to prevent test failures on localized systems - Refactor btf_type_skip_modifiers() to remove ignored id parameter - Sort ERRORS list in trace_probe.h alphabetically - Fix typo in fprobe docs, and trace_fprobe function name - Rename FETCH_OP_DATA to FETCH_OP_IMMSTR - Make file offset error message probe-agnostic" * tag 'probes-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (37 commits) fprobe: Simplify fprobe_remove_ips() by reusing existing helpers tracing/boot: Add support for eprobe, fprobe, and tprobe events selftests/ftrace: Force C locale in ftracetest tracing/probes: Treating longer symbol name on event comparation docs: trace: fprobe: fix 'thos' spelling tracing/probes: Fix extra whitespace in trace_probe_kernel.h tracing/kprobe: Remove redundant memset in kprobe_perf_func() tracing/fprobe: Remove redundant memset in fentry_perf_func() tracing/fprobe: Remove redundant snprintf in trace_fprobe_match_command_head() tracing/probes: Simplify BTF_KIND_PTR case in fetch_type_from_btf_type() tracing/probes: Cleanup pointer arithmetic in store_trace_entry_data() tracing/probes: Remove unused parameter from parse_probe_var_retval() tracing/probes: Remove redundant bounds check in trace_probe_compare_arg_type() tracing/probes: Remove redundant boolean conversion in trace_probe_has_single_file() tracing/probes: Remove duplicate MAX_ARRAY_LEN macro definition selftests/ftrace: Add test case for a symbol in a module without module name tracing/probes: Eliminate recursion in parse_probe_arg() tracing/probes: Extend max length of argument string tracing/probes: Sort ERRORS list in trace_probe.h alphabetically tracing/probes: Refactor parse_probe_arg() ...
2026-08-20Merge tag 'bpf-next-7.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Pull bpf updates from Daniel Borkmann: "Major changes: - Redesign the verifier error reporting: failures now carry source and instruction annotations along with the causal event history that led to them, making program rejections far easier to debug and repair (Kumar Kartikeya Dwivedi) - Add arena argument support to kfuncs and struct_ops through the new __arena and __arena__nullable suffixes (Tejun Heo, Puranjay Mohan, Kumar Kartikeya Dwivedi, Ihor Solodrai) - Signed BPF program loader rework to accommodate both BPF and security community needs where the kernel runs the signature verification at BPF_PROG_LOAD time before the LSM admission hook (Daniel Borkmann) - Add a set of ksock kfuncs which let BPF LSM and syscall programs create, connect and send on UDP sockets in order to emit telemetry data (Mahe Tardy) - Unify helper and kfunc call argument verification and classify kfunc arguments purely from BTF into a generated bpf_func_proto which is computed once at add-call time (Amery Hung) Other features and fixes: - Enable EXECMEM_ROX_CACHE for BPF allocations on x86 (Mike Rapoport) - Add bidirectional VLAN support to bpf_fib_lookup() through the new BPF_FIB_LOOKUP_VLAN and BPF_FIB_LOOKUP_VLAN_INPUT flags (Avinash Duduskar) - Infer zext_dst from static register liveness analysis to fix 32-bit zero-extension semantics, and remove the artificial limitations on pointer types eligible for spilling (Eduard Zingerman) - Inline the numeric open-coded iterator kfuncs so that bpf_for() loops no longer pay a kfunc call on every iteration (Puranjay Mohan) - Add an arena-based bitmap data structure to libarena along with serial and parallel selftests (Emil Tsalapatis) - Teach resolve_btfids to discover kfuncs from the kernel's BTF ID sets and to emit kfunc BTF decl tags, reducing the kernel build's dependency on pahole features (Ihor Solodrai) - Add BPF_F_ADJ_ROOM_DECAP_* flags to bpf_skb_adjust_room() so that tunnel decapsulation can update the GSO and encapsulation state of the skb (Nick Hudson) - Fix the ring buffer pending_pos walk and the available-data accounting on 32-bit position wrap (Israel Téllez García) - Add memory usage accounting for arena maps and fix an mmap_lock deadlock on arena lock failure (Jiayuan Chen) - Add tracing_multi link info support to the kernel UAPI and bpftool, and refactor the stack map code to run with preemption disabled (Jiri Olsa) - Support BPF_F_EGRESS in bpf_redirect_peer() to emit the skb in the egress direction of the target's peer device (Jordan Rife) - Add a KF_SPINLOCK_SAFE kfunc flag so that providers, in particular modules, can declare kfuncs safe to call under bpf_spin_lock instead of relying on the verifier's hard-coded allowlist (Kaitao Cheng) - Introduce global percpu data for BPF programs with libbpf probing and bpftool skeleton support, and stop exposing uninitialized kernel heap memory when copying per-CPU map values (Leon Hwang) - Add s390 JIT support for load-acquire and store-release instructions (Maxim Khmelevskii) - Fix a CFI mismatch in the task work callback and an arm64 KASAN false positive after bpf_throw() (Mykyta Yatsenko) - Reject writes through untrusted BTF pointers and bound the rdonly/rdwr_buf_size kfunc arguments (Nicholas Dudar) - Invalidate RCU pointers only after the final spin unlock and account for preempt and IRQ disabled regions as overlapping RCU protection (Ning Ding) - Support mixing bpf2bpf calls and tail calls on RV64, add signed operations and 32-bit atomics to the RV32 JIT, and add timed may_goto support (Pu Lehui, Kuan-Wei Chiu, Feng Jiang) - Fix a use-after-free on mm_struct in bpf_find_vma() for foreign tasks and an mmap_lock leak in the irq_work path (Sanghyun Park) - Populate mmap-able BPF array map memory lazily which makes mmap() O(1) instead of proportional to the map size (Song Liu) - Introduce a jit_required flag and reject programs with inlined helpers when no JIT is available, where the interpreter would otherwise jump into an invalid address (Tiezhu Yang) - Fix the x86 JIT per-CPU address resolution into an extended register where the REX prefix dropped the high destination register bit (Vineet Gupta) - Reject MEM_ALLOC BTF accesses past object bounds, arena frees below the arena base, and mixed arena and ordinary atomic paths (Yiyang Chen) - Fix the trampoline handling of 128-bit arguments and of return values larger than 8 bytes (Yonghong Song) - Ensure that any fault prone load is rewritten with exception table handling, and fix the arena load-acquire and atomic fetch handling in the x86, arm64, riscv and s390 JITs (Daniel Borkmann) - Many more fixes and cleanups across the verifier, arena, trampolines, sockmap, cgroup, ring buffer, x86/arm64/riscv/s390 JITs, libbpf, bpftool, resolve_btfids and selftests" * tag 'bpf-next-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (373 commits) selftests/bpf: Add tests for a store on a fault prone qdisc pointer selftests/bpf: Add tests for fault prone loads out of RCU pointers selftests/bpf: Add tests for pointer type merge at a shared load selftests/bpf: Remove duplicate copies of the arena spinlock qnodes selftests/bpf: Retry stat generation in cgroup_iter_memcg selftests/bpf: Test pseudo-function policy diagnostics bpf: Distinguish function references in policy diagnostics bpf: Preserve source attribution without source text selftests/bpf: Test kfunc argument diagnostics bpf: Correct kfunc argument diagnostics bpf: Use canonical stack argument names in diagnostics bpf: Preserve R0 lineage across helper calls selftests/bpf: Exercise negative optlen in cgroup getsockopt hook bpf: Reject negative optlen in cgroup getsockopt hook selftests/bpf: tc_tunnel - validate decap GSO and encapsulation state bpf: Clear decap state on skb_adjust_room shrink path bpf: Allow new DECAP flags and add guard rails bpf: Add BPF_F_ADJ_ROOM_DECAP_* flags for tunnel decapsulation bpf: Refactor masks for ADJ_ROOM flags and encap validation bpf: Name the enum for BPF_FUNC_skb_adjust_room flags ...
2026-08-19Merge tag 'trace-ringbuffer-v7.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull ring-buffer updates from Steven Rostedt: - Remove unneeded semicolon A macro ended with a semicolon that wasn't needed. - Fix freeing cpu_buffer extra subbuffer with order greater than zero When the cpu_buffer was being freed, its "free" page, was using free_page() to free it when it could be more than one page. - Hold the cpu_buffer lock when resizing the subbuffer The freeing of the "free" page of the cpu_buffer was done without locking. The order of the data was being saved and then the "free" page was set to NULL. But there is a race that the "free" page could have been updated between those two operations. Add locking around it to prevent the race. - Save the order of the data along with the data in the free page The cpu_buffer would store just the data portion of the subbuffer page in its descriptor. But it did not store the order of the data pages. The order was being saved in the global buffer descriptor. But this leads to races. Have the cpu_buffer save the subbuf data along with its metadata (which includes the order of the page) to make sure when it frees it, it frees the correct order along with it. - Remove the subbuf_size and use the order directly when needed Having a size field for the size of the subbufer along with its order allowed for races to have them get out of sync. Remove the subbuf_size and use the order from the subbuf meta data directly under locks. Use the subbuf_order for other calculations in the ring buffer. - Remove the useless "cpus" field of trace_buffer The code has been restructured and the "cpus" field is no longer used. Remove it. - Remove the "mapped" field of the ring buffer and use a helper function instead. The "mapped" field has become a bit overused and made the code come complex in using a counter for what is denoted as being mapped or not. There are other fields that are set when the ring buffer is considered mapped. Add a helper function to check those fields and use that instead of keeping track of a counter. * tag 'trace-ringbuffer-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Remove ring_buffer_per_cpu::mapped ring-buffer: Remove trace_buffer::cpus ring-buffer: Dynamically calculate max_data_size ring-buffer: Fix subbuf resize race with ring_buffer_alloc_read_page() ring-buffer: Fix subbuf resize race with ring buffer readers ring-buffer: Make cpu_buffer::free_page a buffer_data_read_page ring-buffer: Hold cpu_buffer::lock when resizing a subbuf ring-buffer: Free cpu_buffer::free_page with subbuf_order ring-buffer: drop unneeded semicolon
2026-08-19Merge tag 'tracefs-v7.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracefs updates from Steven Rostedt: - Define event fields before directory creation Move the event_define_fields() call in event_create_dir() before the eventfs directory creation. Previously, a failure after directory creation wouldn't clean up eventfs_inode because the error path didn't call eventfs_remove_dir(). This eliminates the need to clean up the eventfs directories if event_define_fields() fails. - Add warning for out of bounds pos in __eventfs_iterate() Sashiko complains about the ctx->pos causing issues if it is less than 2 or greater than MAX_INT in __eventfs_iterate(). The thing is, the logic prevents that from happening. But to make Sashiko happy, add a WARN_ON() and exit safely if the function ever does get input that is out of the range the function expects. * tag 'tracefs-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: eventfs: Add warning for out of bounds pos in __eventfs_iterate() eventfs: Define event fields before directory creation
2026-08-19Merge tag 'trace-v7.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing updates from Steven Rostedt: - Expose btf_ids to trace events In order to allow BPF programs to attach to system call trace events (which are actually pseudo trace events built on top of raw_syscall events), expose the BTF ID of the events. This will allow BPF programs better precision in attaching to events. - Use "u64" to assign to hist_field->type Instead of using kstrdup("u64", GFP_KERNEL) to assign the hist_field->type, just point it to "u64" instead. The hist_field->type is freed via kfree_const(). - Replace kmalloc()/strcpy() with kstrdup() for trace_printk Instead of having two calls to copy the module format string, just use kstrdup(). - Use __free() in trace event histograms and triggres where possible - Use seq_buf in trace event code instead of strcat() Instead of calculating the size of the buffer to use and filling it with strcat(), use the seq_buf infrastructure that takes care of making sure not to overflow the string size. - Reject invalid preemptirq_delay_test CPU affinity The preempt_delay_test module can take an invalid CPU affinity mask and create confusing output. Simply have the module reject invalid affinity masks. - Prevent division by zero in ftrace_ops sample module code If the ftrace_ops sample module code receives the module parameter nr_function_calls set to zero, it can cause a division by zero error. - Warn when an event dereferences a parameter in TP_printk() On boot up and module load, the trace event TP_printk() is scanned for possible bugs. As the TP_printk() code is executed when the user reads the "trace" file and processes the data written when the trace_event executed, the data it reads can be literally days old. The scan currently checks for dereferencing printk formats like "%pI6". But it does not check if the parameters themselves have a dereference like: TP_printk("offset %08x: value %08x", (u32)(__entry->addr - __entry->edma->membase), __entry->value) __entry represents the pointer to the event on the ring buffer. The __entry->edma->membase is dereferencing a pointer on the ring buffer to find membase, but the __entry->edma may no longer be a valid pointer. Warn on this case too. - Replace some strcpy() with strscpy() - Clean up mmiotrace events to use assign_type() macro The assign_type() macro makes sure the event type is indeed the type that is being parsed. The mmiotrace trace was written before that macro was created so it just simply typecasted the pointer. Replace the typecasting with the macro. - Have the ENUM processing to numbers only process what is added The code that converts ENUMs to their numbers in the trace events scanned all events to do the processing. This was true when a module was loaded too. That is, instead of processing just the events for the module, it processed *all* events. Even the builtin ones that were processed at boot up. Add a check for the event->module matching mod if it is a module before processing it. * tag 'trace-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (21 commits) tracing: Have trace_event_update_all() only handle module that is loading tracing: Cleanup event_enable_trigger_parse() by using __free() tracing: Report every TP_printk double dereference tracing/mmiotrace: Use trace_assign_type() in mmio_print_mark() tracing: Make per-template BTF id lists file-local tracing: Use seq_buf for string concatenation tracing: Use strscpy() instead of strcpy() in trace_sched_switch tracing: Warn when an event dereferences a pointer in TP_printk() samples/ftrace: Prevent division by zero when nr_function_calls is zero tracing: Reject invalid preemptirq_delay_test CPU affinity fgraph: Use trace_seq_putc() in print_graph_return() tracing/user_events: Replace a seq_printf() call by seq_puts() in user_seq_show() tracing/user_events: Use seq_putc() in two functions tracing: Bound histogram expression strings with seq_buf tracing: Return ERR_PTR() from expr_str() tracing: Use __free() for expr_str() buffer kernel/trace/trace_printk: Use kstrdup() instead of kmalloc() and strcpy() tracing: Point constant hist field type to string literal selftests/bpf: Add test for tracepoint btf_ids tracefs file tracing: Expose tracepoint BTF ids via tracefs ...
2026-08-19Merge tag 'ftrace-v7.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull ftrace updates from Steven Rostedt: - Deprecrate ftrace_enabled in disabling ftrace The file /proc/sys/kernel/ftrace_enabled was created when ftrace was first introduced back in 2008. It was to be a "kill switch" if something was to go wrong. It was also used as a way to turn off function tracing for the latency tracers that would have it on by default. But in 2013 (Linux 3.10) the option "function-trace" was introduced to disable function tracing for the latency tracers as the "ftrace_enabled" file was considered too big of a hammer and caused too many side effects. When live kernel patching came along, disabling ftrace via the ftrace_enabled file would put the system into an unstable state if a live kernel patch was installed. This created the need to mark some function hooks as "PERMANENT". Now there's a need for BPF usage marked as PERMANENT for the same reasons. The file "ftrace_enabled" usage is no longer viable. It doesn't do what it says it does and there is no reason to use it. Make writing '0' to it a nop and print a message saying its usage is deprecated. The return value of writing '0' is -EOPNOTSUPP so that user space will error on that write (hopefully to inform any developer that it no longer works). Eventually the file should be removed completely, but for now just making it not do anything is the path forward to that. - Update the livepatch tests to handle ftrace_enabled being disabled Because in the past, livepatch was broken by ftrace_enabled being turned off, there's a test case that checks to make sure it still doesn't break. But having the write of '0' return an error caused that test to break. Updated the test to handle the new change. * tag 'ftrace-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: selftests/livepatch: update test-ftrace.sh for deprecated ftrace_enabled ftrace: deprecate disabling via ftrace_enabled sysctl
2026-08-19Merge tag 'trace-rv-v7.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull Real-time Verifier updates from Steven Rostedt: - Switch LTL and DOT parsers to Lark in code generation tool The rvgen code generation tool originally parsed DOT files and LTL specifications using custom string parsing and Ply, which is no longer maintained. The DOT parser was fragile and prone to failure on minor format variations. Both LTL and DOT parsers have been rewritten to use the Lark parsing library. - Simplify Hybrid Automata clock variables The clock variables in hybrid automata monitors now use a single representation of the elapsed time since the clock was reset, rather than converting between invariant and guard representations. This allows simpler code generation for the newly refactored parser. - Generate cleanup hook for per-obj monitor The code generation scripts now adds a cleanup function to per-obj monitors for the user to wire to the appropriate event (e.g. sched_process_exit for tasks). - Reduce read_lock scope during per-task cleanup Take the tasklist_lock only when necessary, that is when iterating over for_each_process_thread(). - Simplify task monitor slot management Only rely on the slot array for per-task slot management to avoid inconsistency with the unused counter. - Improve rvgen code robustness and templates Use pathlib in rvgen and improve kernel path discovery. Also improve consistency across templates when generating code (e.g. author placeholder and monitor struct name). - Update rtapp sleep monitor Simplify the sleep monitor by excluding kernel threads and updating the nanosleep check to focus only on CLOCK_REALTIME. Also switch to use the sched_exit tracepoint to run in the context of the offending (wakee) task. - Add wakeup monitor Add the new rtapp/wakeup monitor to detect when lower-priority tasks wake up higher-priority ones, complementing the existing sleep monitor by running in the waker context and capturing its stack trace. - Fix tools/rv exit status on failure Ensure the rv tool returns a failure exit code when a monitor fails to start because it was already running. - Add automated selftests for tools/rv and rvgen Introduced automated bash selftests to validate rv monitor listing and execution under different configurations. Added tests for the rvgen code generator, validating generated files against expected output (golden). Tests are reachable via make check. - Add KUnit test coverage for verification monitors Added comprehensive KUnit tests to validate the functionality of deterministic, hybrid, and LTL monitors by emulating event sequences and timing in a mock environment without affecting the running kernel while expecting mock reactions to fire. Ensure real RV monitors cannot run during KUnit tests to avoid state corruption. - Mock current in rv monitors Mock the call to current in rv monitors when the KUnit tests are built to allow them to run the test on dummy tasks. No overhead is expected when KUnit tests aren't running. - Introduce rvgen kunit subcommand Added a new 'kunit' subcommand to rvgen to automatically patch an already generated monitor with KUnit integration templates by parsing its event handlers and creating the required mock structures and initializations. - Refine kernel verification selftests Added new selftests for the deadline and stall monitors and rearranged the existing wwnr_printk test to resolve flakiness. Additionally, fixed an issue in the selftests framework where negative assertion failures were not correctly propagated due to shell rules. - Fix 32-bit build of nomiss KUnit test A previous commit introduced a division between an u64 and a constant value and that doesn't build on 32-bit systems. Use div_u64() instead. - Document changes in sleep monitor The sleep monitor introduced some changes in the past like allowing epoll_wait() as a valid sleep and a task going to runnable before scheduling as a valid wakeup. Document both. * tag 'trace-rv-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (40 commits) Documentation/rv: Explain epoll and aborted sleeps rv: Fix 32-bit build of nomiss KUnit test selftests/verification: Add selftests for deadline and stall monitors selftests/verification: Rearrange the wwnr_printk test selftests/verification: Fix wrong errexit assumption rv: Add KUnit tests for some LTL monitors rv: Add KUnit mock for current rv: Add KUnit tests for some DA/HA monitors rv: Export task monitor slot and react symbols verification/rvgen: Add selftests for rvgen kunit verification/rvgen: Add the rvgen kunit subcommand verification/rvgen: Add selftests verification/rvgen: Add golden and spec folders for tests tools/rv: Add selftests verification/rvgen: Improve consistency in template files verification/rvgen: Use pathlib instead of os.path verification/rvgen: Improve rv_dir discovery in RVGenerator tools/rv: Fix exit status when monitor execution fails rv: Use generic rv_this for the rv_monitor variable in LTL rv/rtapp: Add wakeup monitor ...
2026-08-14ring-buffer: Remove ring_buffer_per_cpu::mappedVincent Donnefort
ring_buffer_per_cpu::mapped tracks if a ring-buffer is either mapped by user-space or if it is a persistent buffer. We already have user_mapped for the former and ring_meta for the latter. Get rid of mapped and instead create rb_is_static(). A static ring-buffer cannot be resized, swapped or have its pages extracted. Link: https://patch.msgid.link/20260813131152.3589632-10-vdonnefort@google.com Signed-off-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-14ring-buffer: Remove trace_buffer::cpusVincent Donnefort
The 'cpus' field in struct trace_buffer became useless in commit 8e7b58c27b3c ("ring-buffer: Just update the subbuffers when changing their allocation order"). Remove it Link: https://patch.msgid.link/20260813131152.3589632-9-vdonnefort@google.com Fixes: 8e7b58c27b3c ("ring-buffer: Just update the subbuffers when changing their allocation order") Signed-off-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>