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2015-09-17cpuset: use trialcs->mems_allowed as a temp variableAlban Crequy
[ Upstream commit 24ee3cf89bef04e8bc23788aca4e029a3f0f06d9 ] The comment says it's using trialcs->mems_allowed as a temp variable but it didn't match the code. Change the code to match the comment. This fixes an issue when writing in cpuset.mems when a sub-directory exists: we need to write several times for the information to persist: | root@alban:/sys/fs/cgroup/cpuset# mkdir footest9 | root@alban:/sys/fs/cgroup/cpuset# cd footest9 | root@alban:/sys/fs/cgroup/cpuset/footest9# mkdir aa | root@alban:/sys/fs/cgroup/cpuset/footest9# cat cpuset.mems | | root@alban:/sys/fs/cgroup/cpuset/footest9# echo 0 > cpuset.mems | root@alban:/sys/fs/cgroup/cpuset/footest9# cat cpuset.mems | | root@alban:/sys/fs/cgroup/cpuset/footest9# echo 0 > cpuset.mems | root@alban:/sys/fs/cgroup/cpuset/footest9# cat cpuset.mems | 0 | root@alban:/sys/fs/cgroup/cpuset/footest9# cat aa/cpuset.mems | | root@alban:/sys/fs/cgroup/cpuset/footest9# echo 0 > aa/cpuset.mems | root@alban:/sys/fs/cgroup/cpuset/footest9# cat aa/cpuset.mems | 0 | root@alban:/sys/fs/cgroup/cpuset/footest9# This should help to fix the following issue in Docker: https://github.com/opencontainers/runc/issues/133 In some conditions, a Docker container needs to be started twice in order to work. Signed-off-by: Alban Crequy <alban@endocode.com> Tested-by: Iago López Galeiras <iago@endocode.com> Cc: <stable@vger.kernel.org> # 3.17+ Acked-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-09-15perf: Fix PERF_EVENT_IOC_PERIOD migration racePeter Zijlstra
[ Upstream commit c7999c6f3fed9e383d3131474588f282ae6d56b9 ] I ran the perf fuzzer, which triggered some WARN()s which are due to trying to stop/restart an event on the wrong CPU. Use the normal IPI pattern to ensure we run the code on the correct CPU. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: bad7192b842c ("perf: Fix PERF_EVENT_IOC_PERIOD to force-reset the period") Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-09-15perf: Fix fasync handling on inherited eventsPeter Zijlstra
[ Upstream commit fed66e2cdd4f127a43fd11b8d92a99bdd429528c ] Vince reported that the fasync signal stuff doesn't work proper for inherited events. So fix that. Installing fasync allocates memory and sets filp->f_flags |= FASYNC, which upon the demise of the file descriptor ensures the allocation is freed and state is updated. Now for perf, we can have the events stick around for a while after the original FD is dead because of references from child events. So we cannot copy the fasync pointer around. We can however consistently use the parent's fasync, as that will be updated. Reported-and-Tested-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> Cc: Arnaldo Carvalho deMelo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: eranian@google.com Link: http://lkml.kernel.org/r/1434011521.1495.71.camel@twins Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-08-27kexec: allocate the kexec control page with KEXEC_CONTROL_MEMORY_GFPMartin Schwidefsky
[ Upstream commit 7e01b5acd88b3f3108d8c4ce44e3205d67437202 ] Introduce KEXEC_CONTROL_MEMORY_GFP to allow the architecture code to override the gfp flags of the allocation for the kexec control page. The loop in kimage_alloc_normal_control_pages allocates pages with GFP_KERNEL until a page is found that happens to have an address smaller than the KEXEC_CONTROL_MEMORY_LIMIT. On systems with a large memory size but a small KEXEC_CONTROL_MEMORY_LIMIT the loop will keep allocating memory until the oom killer steps in. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-08-27genirq: Prevent resend to interrupts marked IRQ_NESTED_THREADThomas Gleixner
[ Upstream commit 75a06189fc508a2acf470b0b12710362ffb2c4b1 ] The resend mechanism happily calls the interrupt handler of interrupts which are marked IRQ_NESTED_THREAD from softirq context. This can result in crashes because the interrupt handler is not the proper way to invoke the device handlers. They must be invoked via handle_nested_irq. Prevent the resend even if the interrupt has no valid parent irq set. Its better to have a lost interrupt than a crashing machine. Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-08-27signal: fix information leak in copy_siginfo_from_user32Amanieu d'Antras
[ Upstream commit 3c00cb5e68dc719f2fc73a33b1b230aadfcb1309 ] This function can leak kernel stack data when the user siginfo_t has a positive si_code value. The top 16 bits of si_code descibe which fields in the siginfo_t union are active, but they are treated inconsistently between copy_siginfo_from_user32, copy_siginfo_to_user32 and copy_siginfo_to_user. copy_siginfo_from_user32 is called from rt_sigqueueinfo and rt_tgsigqueueinfo in which the user has full control overthe top 16 bits of si_code. This fixes the following information leaks: x86: 8 bytes leaked when sending a signal from a 32-bit process to itself. This leak grows to 16 bytes if the process uses x32. (si_code = __SI_CHLD) x86: 100 bytes leaked when sending a signal from a 32-bit process to a 64-bit process. (si_code = -1) sparc: 4 bytes leaked when sending a signal from a 32-bit process to a 64-bit process. (si_code = any) parsic and s390 have similar bugs, but they are not vulnerable because rt_[tg]sigqueueinfo have checks that prevent sending a positive si_code to a different process. These bugs are also fixed for consistency. Signed-off-by: Amanieu d'Antras <amanieu@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-08-27signal: fix information leak in copy_siginfo_to_userAmanieu d'Antras
[ Upstream commit c08a75d950725cdd87c19232a5a3850c51520359 ] commit 26135022f85105ad725cda103fa069e29e83bd16 upstream. This function may copy the si_addr_lsb, si_lower and si_upper fields to user mode when they haven't been initialized, which can leak kernel stack data to user mode. Just checking the value of si_code is insufficient because the same si_code value is shared between multiple signals. This is solved by checking the value of si_signo in addition to si_code. Signed-off-by: Amanieu d'Antras <amanieu@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-08-04security_syslog() should be called once onlyVasily Averin
[ Upstream commit d194e5d666225b04c7754471df0948f645b6ab3a ] The final version of commit 637241a900cb ("kmsg: honor dmesg_restrict sysctl on /dev/kmsg") lost few hooks, as result security_syslog() are processed incorrectly: - open of /dev/kmsg checks syslog access permissions by using check_syslog_permissions() where security_syslog() is not called if dmesg_restrict is set. - syslog syscall and /proc/kmsg calls do_syslog() where security_syslog can be executed twice (inside check_syslog_permissions() and then directly in do_syslog()) With this patch security_syslog() is called once only in all syslog-related operations regardless of dmesg_restrict value. Fixes: 637241a900cb ("kmsg: honor dmesg_restrict sysctl on /dev/kmsg") Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Cc: Kees Cook <keescook@chromium.org> Cc: Josh Boyer <jwboyer@redhat.com> Cc: Eric Paris <eparis@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-08-04tracing: Have branch tracer use recursive field of task structSteven Rostedt (Red Hat)
[ Upstream commit 6224beb12e190ff11f3c7d4bf50cb2922878f600 ] Fengguang Wu's tests triggered a bug in the branch tracer's start up test when CONFIG_DEBUG_PREEMPT set. This was because that config adds some debug logic in the per cpu field, which calls back into the branch tracer. The branch tracer has its own recursive checks, but uses a per cpu variable to implement it. If retrieving the per cpu variable calls back into the branch tracer, you can see how things will break. Instead of using a per cpu variable, use the trace_recursion field of the current task struct. Simply set a bit when entering the branch tracing and clear it when leaving. If the bit is set on entry, just don't do the tracing. There's also the case with lockdep, as the local_irq_save() called before the recursion can also trigger code that can call back into the function. Changing that to a raw_local_irq_save() will protect that as well. This prevents the recursion and the inevitable crash that follows. Link: http://lkml.kernel.org/r/20150630141803.GA28071@wfg-t540p.sh.intel.com Cc: stable@vger.kernel.org # 3.10+ Reported-by: Fengguang Wu <fengguang.wu@intel.com> Tested-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-08-04tracing/filter: Do not WARN on operand count going below zeroSteven Rostedt (Red Hat)
[ Upstream commit b4875bbe7e68f139bd3383828ae8e994a0df6d28 ] When testing the fix for the trace filter, I could not come up with a scenario where the operand count goes below zero, so I added a WARN_ON_ONCE(cnt < 0) to the logic. But there is legitimate case that it can happen (although the filter would be wrong). # echo '>' > /sys/kernel/debug/events/ext4/ext4_truncate_exit/filter That is, a single operation without any operands will hit the path where the WARN_ON_ONCE() can trigger. Although this is harmless, and the filter is reported as a error. But instead of spitting out a warning to the kernel dmesg, just fail nicely and report it via the proper channels. Link: http://lkml.kernel.org/r/558C6082.90608@oracle.com Reported-by: Vince Weaver <vincent.weaver@maine.edu> Reported-by: Sasha Levin <sasha.levin@oracle.com> Cc: stable@vger.kernel.org # 2.6.33+ Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-07-13perf: Fix ring_buffer_attach() RCU sync, againOleg Nesterov
[ Upstream commit 2f993cf093643b98477c421fa2b9a98dcc940323 ] While looking for other users of get_state/cond_sync. I Found ring_buffer_attach() and it looks obviously buggy? Don't we need to ensure that we have "synchronize" _between_ list_del() and list_add() ? IOW. Suppose that ring_buffer_attach() preempts right_after get_state_synchronize_rcu() and gp completes before spin_lock(). In this case cond_synchronize_rcu() does nothing and we reuse ->rb_entry without waiting for gp in between? It also moves the ->rcu_pending check under "if (rb)", to make it more readable imo. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave@stgolabs.net Cc: der.herr@hofr.at Cc: josh@joshtriplett.org Cc: tj@kernel.org Fixes: b69cf53640da ("perf: Fix a race between ring_buffer_detach() and ring_buffer_attach()") Link: http://lkml.kernel.org/r/20150530200425.GA15748@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-07-13tracing: Have filter check for balanced opsSteven Rostedt
[ Upstream commit 2cf30dc180cea808077f003c5116388183e54f9e ] When the following filter is used it causes a warning to trigger: # cd /sys/kernel/debug/tracing # echo "((dev==1)blocks==2)" > events/ext4/ext4_truncate_exit/filter -bash: echo: write error: Invalid argument # cat events/ext4/ext4_truncate_exit/filter ((dev==1)blocks==2) ^ parse_error: No error ------------[ cut here ]------------ WARNING: CPU: 2 PID: 1223 at kernel/trace/trace_events_filter.c:1640 replace_preds+0x3c5/0x990() Modules linked in: bnep lockd grace bluetooth ... CPU: 3 PID: 1223 Comm: bash Tainted: G W 4.1.0-rc3-test+ #450 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v02.05 05/07/2012 0000000000000668 ffff8800c106bc98 ffffffff816ed4f9 ffff88011ead0cf0 0000000000000000 ffff8800c106bcd8 ffffffff8107fb07 ffffffff8136b46c ffff8800c7d81d48 ffff8800d4c2bc00 ffff8800d4d4f920 00000000ffffffea Call Trace: [<ffffffff816ed4f9>] dump_stack+0x4c/0x6e [<ffffffff8107fb07>] warn_slowpath_common+0x97/0xe0 [<ffffffff8136b46c>] ? _kstrtoull+0x2c/0x80 [<ffffffff8107fb6a>] warn_slowpath_null+0x1a/0x20 [<ffffffff81159065>] replace_preds+0x3c5/0x990 [<ffffffff811596b2>] create_filter+0x82/0xb0 [<ffffffff81159944>] apply_event_filter+0xd4/0x180 [<ffffffff81152bbf>] event_filter_write+0x8f/0x120 [<ffffffff811db2a8>] __vfs_write+0x28/0xe0 [<ffffffff811dda43>] ? __sb_start_write+0x53/0xf0 [<ffffffff812e51e0>] ? security_file_permission+0x30/0xc0 [<ffffffff811dc408>] vfs_write+0xb8/0x1b0 [<ffffffff811dc72f>] SyS_write+0x4f/0xb0 [<ffffffff816f5217>] system_call_fastpath+0x12/0x6a ---[ end trace e11028bd95818dcd ]--- Worse yet, reading the error message (the filter again) it says that there was no error, when there clearly was. The issue is that the code that checks the input does not check for balanced ops. That is, having an op between a closed parenthesis and the next token. This would only cause a warning, and fail out before doing any real harm, but it should still not caues a warning, and the error reported should work: # cd /sys/kernel/debug/tracing # echo "((dev==1)blocks==2)" > events/ext4/ext4_truncate_exit/filter -bash: echo: write error: Invalid argument # cat events/ext4/ext4_truncate_exit/filter ((dev==1)blocks==2) ^ parse_error: Meaningless filter expression And give no kernel warning. Link: http://lkml.kernel.org/r/20150615175025.7e809215@gandalf.local.home Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: stable@vger.kernel.org # 2.6.31+ Reported-by: Vince Weaver <vincent.weaver@maine.edu> Tested-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-07-05tracing/filter: Do not allow infix to exceed end of stringSteven Rostedt (Red Hat)
[ Upstream commit 6b88f44e161b9ee2a803e5b2b1fbcf4e20e8b980 ] While debugging a WARN_ON() for filtering, I found that it is possible for the filter string to be referenced after its end. With the filter: # echo '>' > /sys/kernel/debug/events/ext4/ext4_truncate_exit/filter The filter_parse() function can call infix_get_op() which calls infix_advance() that updates the infix filter pointers for the cnt and tail without checking if the filter is already at the end, which will put the cnt to zero and the tail beyond the end. The loop then calls infix_next() that has ps->infix.cnt--; return ps->infix.string[ps->infix.tail++]; The cnt will now be below zero, and the tail that is returned is already passed the end of the filter string. So far the allocation of the filter string usually has some buffer that is zeroed out, but if the filter string is of the exact size of the allocated buffer there's no guarantee that the charater after the nul terminating character will be zero. Luckily, only root can write to the filter. Cc: stable@vger.kernel.org # 2.6.33+ Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-07-05PM / sleep: Increase default DPM watchdog timeout to 60Takashi Iwai
[ Upstream commit fff3b16d2754a061a3549c4307a186423a0128fd ] Many harddisks (mostly WD ones) have firmware problems and take too long, more than 10 seconds, to resume from suspend. And this often exceeds the default DPM watchdog timeout (12 seconds), resulting in a kernel panic out of sudden. Since most distros just take the default as is, we should give a bit more safer value. This patch increases the default value from 12 seconds to one minute, which has been confirmed to be long enough for such problematic disks. Link: https://bugzilla.kernel.org/show_bug.cgi?id=91921 Fixes: 70fea60d888d (PM / Sleep: Detect device suspend/resume lockup and log event) Cc: 3.13+ <stable@vger.kernel.org> # 3.13+ Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-07-03rcu: Correctly handle non-empty Tiny RCU callback list with none readyPaul E. McKenney
[ Upstream commit 6e91f8cb138625be96070b778d9ba71ce520ea7e ] If, at the time __rcu_process_callbacks() is invoked, there are callbacks in Tiny RCU's callback list, but none of them are ready to be invoked, the current list-management code will knit the non-ready callbacks out of the list. This can result in hangs and possibly worse. This commit therefore inserts a check for there being no callbacks that can be invoked immediately. This bug is unlikely to occur -- you have to get a new callback between the time rcu_sched_qs() or rcu_bh_qs() was called, but before we get to __rcu_process_callbacks(). It was detected by the addition of RCU-bh testing to rcutorture, which in turn was instigated by Iftekhar Ahmed's mutation testing. Although this bug was made much more likely by 915e8a4fe45e (rcu: Remove fastpath from __rcu_process_callbacks()), this did not cause the bug, but rather made it much more probable. That said, it takes more than 40 hours of rcutorture testing, on average, for this bug to appear, so this fix cannot be considered an emergency. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-07-03genirq: devres: Fix testing return value of request_any_context_irq()Axel Lin
[ Upstream commit 63781394c540dd9e666a6b21d70b64dd52bce76e ] request_any_context_irq() returns a negative value on failure. It returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED on success. So fix testing return value of request_any_context_irq(). Also fixup the return value of devm_request_any_context_irq() to make it consistent with request_any_context_irq(). Fixes: 0668d3065128 ("genirq: Add devm_request_any_context_irq()") Signed-off-by: Axel Lin <axel.lin@ingics.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1431334978.17783.4.camel@ingics.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-07-03ring-buffer-benchmark: Fix the wrong sched_priority of producerWang Long
[ Upstream commit 108029323910c5dd1ef8fa2d10da1ce5fbce6e12 ] The producer should be used producer_fifo as its sched_priority, so correct it. Link: http://lkml.kernel.org/r/1433923957-67842-1-git-send-email-long.wanglong@huawei.com Cc: stable@vger.kernel.org # 2.6.33+ Signed-off-by: Wang Long <long.wanglong@huawei.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-07-03ksoftirqd: Enable IRQs and call cond_resched() before poking RCUCalvin Owens
[ Upstream commit 28423ad283d5348793b0c45cc9b1af058e776fd6 ] While debugging an issue with excessive softirq usage, I encountered the following note in commit 3e339b5dae24a706 ("softirq: Use hotplug thread infrastructure"): [ paulmck: Call rcu_note_context_switch() with interrupts enabled. ] ...but despite this note, the patch still calls RCU with IRQs disabled. This seemingly innocuous change caused a significant regression in softirq CPU usage on the sending side of a large TCP transfer (~1 GB/s): when introducing 0.01% packet loss, the softirq usage would jump to around 25%, spiking as high as 50%. Before the change, the usage would never exceed 5%. Moving the call to rcu_note_context_switch() after the cond_sched() call, as it was originally before the hotplug patch, completely eliminated this problem. Signed-off-by: Calvin Owens <calvinowens@fb.com> Cc: stable@vger.kernel.org Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-06-22sched, numa: Do not hint for NUMA balancing on VM_MIXEDMAP mappingsMel Gorman
commit 8e76d4eecf7afeec9328e21cd5880e281838d0d6 upstream. Jovi Zhangwei reported the following problem Below kernel vm bug can be triggered by tcpdump which mmaped a lot of pages with GFP_COMP flag. [Mon May 25 05:29:33 2015] page:ffffea0015414000 count:66 mapcount:1 mapping: (null) index:0x0 [Mon May 25 05:29:33 2015] flags: 0x20047580004000(head) [Mon May 25 05:29:33 2015] page dumped because: VM_BUG_ON_PAGE(compound_order(page) && !PageTransHuge(page)) [Mon May 25 05:29:33 2015] ------------[ cut here ]------------ [Mon May 25 05:29:33 2015] kernel BUG at mm/migrate.c:1661! [Mon May 25 05:29:33 2015] invalid opcode: 0000 [#1] SMP In this case it was triggered by running tcpdump but it's not necessary reproducible on all systems. sudo tcpdump -i bond0.100 'tcp port 4242' -c 100000000000 -w 4242.pcap Compound pages cannot be migrated and it was not expected that such pages be marked for NUMA balancing. This did not take into account that drivers such as net/packet/af_packet.c may insert compound pages into userspace with vm_insert_page. This patch tells the NUMA balancing protection scanner to skip all VM_MIXEDMAP mappings which avoids the possibility that compound pages are marked for migration. Signed-off-by: Mel Gorman <mgorman@suse.de> Reported-by: Jovi Zhangwei <jovi@cloudflare.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [jovi: Backported to 3.18: adjust context] Signed-off-by: Jovi Zhangwei <jovi@cloudflare.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-06-10sched: Handle priority boosted tasks proper in setscheduler()Thomas Gleixner
[ Upstream commit 0782e63bc6fe7e2d3408d250df11d388b7799c6b ] Ronny reported that the following scenario is not handled correctly: T1 (prio = 10) lock(rtmutex); T2 (prio = 20) lock(rtmutex) boost T1 T1 (prio = 20) sys_set_scheduler(prio = 30) T1 prio = 30 .... sys_set_scheduler(prio = 10) T1 prio = 30 The last step is wrong as T1 should now be back at prio 20. Commit c365c292d059 ("sched: Consider pi boosting in setscheduler()") only handles the case where a boosted tasks tries to lower its priority. Fix it by taking the new effective priority into account for the decision whether a change of the priority is required. Reported-by: Ronny Meeus <ronny.meeus@gmail.com> Tested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: <stable@vger.kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Fixes: c365c292d059 ("sched: Consider pi boosting in setscheduler()") Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1505051806060.4225@nanos Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-06-09module: Call module notifier on failure after complete_formation()Steven Rostedt
[ Upstream commit 37815bf866ab6722a47550f8d25ad3f1a16a680c ] The module notifier call chain for MODULE_STATE_COMING was moved up before the parsing of args, into the complete_formation() call. But if the module failed to load after that, the notifier call chain for MODULE_STATE_GOING was never called and that prevented the users of those call chains from cleaning up anything that was allocated. Link: http://lkml.kernel.org/r/554C52B9.9060700@gmail.com Reported-by: Pontus Fuchs <pontus.fuchs@gmail.com> Fixes: 4982223e51e8 "module: set nx before marking module MODULE_STATE_COMING" Cc: stable@vger.kernel.org # 3.16+ Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-06-09ktime: Fix ktime_divns to do signed divisionJohn Stultz
[ Upstream commit f7bcb70ebae0dcdb5a2d859b09e4465784d99029 ] It was noted that the 32bit implementation of ktime_divns() was doing unsigned division and didn't properly handle negative values. And when a ktime helper was changed to utilize ktime_divns, it caused a regression on some IR blasters. See the following bugzilla for details: https://bugzilla.redhat.com/show_bug.cgi?id=1200353 This patch fixes the problem in ktime_divns by checking and preserving the sign bit, and then reapplying it if appropriate after the division, it also changes the return type to a s64 to make it more obvious this is expected. Nicolas also pointed out that negative dividers would cause infinite loops on 32bit systems, negative dividers is unlikely for users of this function, but out of caution this patch adds checks for negative dividers for both 32-bit (BUG_ON) and 64-bit(WARN_ON) versions to make sure no such use cases creep in. [ tglx: Hand an u64 to do_div() to avoid the compiler warning ] Fixes: 166afb64511e 'ktime: Sanitize ktime_to_us/ms conversion' Reported-and-tested-by: Trevor Cordes <trevor@tecnopolis.ca> Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Boyer <jwboyer@redhat.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1431118043-23452-1-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-06-09ktime: Optimize ktime_divns for constant divisorsNicolas Pitre
[ Upstream commit 8b618628b2bf83512fc8df5e8672619d65adfdfb ] At least on ARM, do_div() is optimized to turn constant divisors into an inline multiplication by the reciprocal value at compile time. However this optimization is missed entirely whenever ktime_divns() is used and the slow out-of-line division code is used all the time. Let ktime_divns() use do_div() inline whenever the divisor is constant and small enough. This will make things like ktime_to_us() and ktime_to_ms() much faster. Cc: Arnd Bergmann <arnd.bergmann@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Nicolas Pitre <nico@linaro.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-05-17bpf: fix 64-bit divideAlexei Starovoitov
[ Upstream commit 876a7ae65b86d8cec8efe7d15d050ac61116874e ] ALU64_DIV instruction should be dividing 64-bit by 64-bit, whereas do_div() does 64-bit by 32-bit divide. x64 and arm64 JITs correctly implement 64 by 64 unsigned divide. llvm BPF backend emits code assuming that ALU64_DIV does 64 by 64. Fixes: 89aa075832b0 ("net: sock: allow eBPF programs to be attached to sockets") Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-05-17ebpf: verifier: check that call reg with ARG_ANYTHING is initializedDaniel Borkmann
[ Upstream commit 80f1d68ccba70b1060c9c7360ca83da430f66bed ] I noticed that a helper function with argument type ARG_ANYTHING does not need to have an initialized value (register). This can worst case lead to unintented stack memory leakage in future helper functions if they are not carefully designed, or unintended application behaviour in case the application developer was not careful enough to match a correct helper function signature in the API. The underlying issue is that ARG_ANYTHING should actually be split into two different semantics: 1) ARG_DONTCARE for function arguments that the helper function does not care about (in other words: the default for unused function arguments), and 2) ARG_ANYTHING that is an argument actually being used by a helper function and *guaranteed* to be an initialized register. The current risk is low: ARG_ANYTHING is only used for the 'flags' argument (r4) in bpf_map_update_elem() that internally does strict checking. Fixes: 17a5267067f3 ("bpf: verifier (add verifier core)") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-05-17tracing: Handle ftrace_dump() atomic context in graph_trace_open()Rabin Vincent
[ Upstream commit ef99b88b16bee753fa51207abdc58ae660453ec6 ] graph_trace_open() can be called in atomic context from ftrace_dump(). Use GFP_ATOMIC for the memory allocations when that's the case, in order to avoid the following splat. BUG: sleeping function called from invalid context at mm/slab.c:2849 in_atomic(): 1, irqs_disabled(): 128, pid: 0, name: swapper/0 Backtrace: .. [<8004dc94>] (__might_sleep) from [<801371f4>] (kmem_cache_alloc_trace+0x160/0x238) r7:87800040 r6:000080d0 r5:810d16e8 r4:000080d0 [<80137094>] (kmem_cache_alloc_trace) from [<800cbd60>] (graph_trace_open+0x30/0xd0) r10:00000100 r9:809171a8 r8:00008e28 r7:810d16f0 r6:00000001 r5:810d16e8 r4:810d16f0 [<800cbd30>] (graph_trace_open) from [<800c79c4>] (trace_init_global_iter+0x50/0x9c) r8:00008e28 r7:808c853c r6:00000001 r5:810d16e8 r4:810d16f0 r3:800cbd30 [<800c7974>] (trace_init_global_iter) from [<800c7aa0>] (ftrace_dump+0x90/0x2ec) r4:810d2580 r3:00000000 [<800c7a10>] (ftrace_dump) from [<80414b2c>] (sysrq_ftrace_dump+0x1c/0x20) r10:00000100 r9:809171a8 r8:808f6e7c r7:00000001 r6:00000007 r5:0000007a r4:808d5394 [<80414b10>] (sysrq_ftrace_dump) from [<800169b8>] (return_to_handler+0x0/0x18) [<80415498>] (__handle_sysrq) from [<800169b8>] (return_to_handler+0x0/0x18) r8:808c8100 r7:808c8444 r6:00000101 r5:00000010 r4:84eb3210 [<80415668>] (handle_sysrq) from [<800169b8>] (return_to_handler+0x0/0x18) [<8042a760>] (pl011_int) from [<800169b8>] (return_to_handler+0x0/0x18) r10:809171bc r9:809171a8 r8:00000001 r7:00000026 r6:808c6000 r5:84f01e60 r4:8454fe00 [<8007782c>] (handle_irq_event_percpu) from [<80077b44>] (handle_irq_event+0x4c/0x6c) r10:808c7ef0 r9:87283e00 r8:00000001 r7:00000000 r6:8454fe00 r5:84f01e60 r4:84f01e00 [<80077af8>] (handle_irq_event) from [<8007aa28>] (handle_fasteoi_irq+0xf0/0x1ac) r6:808f52a4 r5:84f01e60 r4:84f01e00 r3:00000000 [<8007a938>] (handle_fasteoi_irq) from [<80076dc0>] (generic_handle_irq+0x3c/0x4c) r6:00000026 r5:00000000 r4:00000026 r3:8007a938 [<80076d84>] (generic_handle_irq) from [<80077128>] (__handle_domain_irq+0x8c/0xfc) r4:808c1e38 r3:0000002e [<8007709c>] (__handle_domain_irq) from [<800087b8>] (gic_handle_irq+0x34/0x6c) r10:80917748 r9:00000001 r8:88802100 r7:808c7ef0 r6:808c8fb0 r5:00000015 r4:8880210c r3:808c7ef0 [<80008784>] (gic_handle_irq) from [<80014044>] (__irq_svc+0x44/0x7c) Link: http://lkml.kernel.org/r/1428953721-31349-1-git-send-email-rabin@rab.in Link: http://lkml.kernel.org/r/1428957012-2319-1-git-send-email-rabin@rab.in Cc: stable@vger.kernel.org # 3.13+ Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-05-17ptrace: fix race between ptrace_resume() and wait_task_stopped()Oleg Nesterov
[ Upstream commit b72c186999e689cb0b055ab1c7b3cd8fffbeb5ed ] ptrace_resume() is called when the tracee is still __TASK_TRACED. We set tracee->exit_code and then wake_up_state() changes tracee->state. If the tracer's sub-thread does wait() in between, task_stopped_code(ptrace => T) wrongly looks like another report from tracee. This confuses debugger, and since wait_task_stopped() clears ->exit_code the tracee can miss a signal. Test-case: #include <stdio.h> #include <unistd.h> #include <sys/wait.h> #include <sys/ptrace.h> #include <pthread.h> #include <assert.h> int pid; void *waiter(void *arg) { int stat; for (;;) { assert(pid == wait(&stat)); assert(WIFSTOPPED(stat)); if (WSTOPSIG(stat) == SIGHUP) continue; assert(WSTOPSIG(stat) == SIGCONT); printf("ERR! extra/wrong report:%x\n", stat); } } int main(void) { pthread_t thread; pid = fork(); if (!pid) { assert(ptrace(PTRACE_TRACEME, 0,0,0) == 0); for (;;) kill(getpid(), SIGHUP); } assert(pthread_create(&thread, NULL, waiter, NULL) == 0); for (;;) ptrace(PTRACE_CONT, pid, 0, SIGCONT); return 0; } Note for stable: the bug is very old, but without 9899d11f6544 "ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL" the fix should use lock_task_sighand(child). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reported-by: Pavel Labath <labath@google.com> Tested-by: Pavel Labath <labath@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-05-17ring-buffer: Replace this_cpu_*() with __this_cpu_*()Steven Rostedt
[ Upstream commit 80a9b64e2c156b6523e7a01f2ba6e5d86e722814 ] It has come to my attention that this_cpu_read/write are horrible on architectures other than x86. Worse yet, they actually disable preemption or interrupts! This caused some unexpected tracing results on ARM. 101.356868: preempt_count_add <-ring_buffer_lock_reserve 101.356870: preempt_count_sub <-ring_buffer_lock_reserve The ring_buffer_lock_reserve has recursion protection that requires accessing a per cpu variable. But since preempt_disable() is traced, it too got traced while accessing the variable that is suppose to prevent recursion like this. The generic version of this_cpu_read() and write() are: #define this_cpu_generic_read(pcp) \ ({ typeof(pcp) ret__; \ preempt_disable(); \ ret__ = *this_cpu_ptr(&(pcp)); \ preempt_enable(); \ ret__; \ }) #define this_cpu_generic_to_op(pcp, val, op) \ do { \ unsigned long flags; \ raw_local_irq_save(flags); \ *__this_cpu_ptr(&(pcp)) op val; \ raw_local_irq_restore(flags); \ } while (0) Which is unacceptable for locations that know they are within preempt disabled or interrupt disabled locations. Paul McKenney stated that __this_cpu_() versions produce much better code on other architectures than this_cpu_() does, if we know that the call is done in a preempt disabled location. I also changed the recursive_unlock() to use two local variables instead of accessing the per_cpu variable twice. Link: http://lkml.kernel.org/r/20150317114411.GE3589@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/20150317104038.312e73d1@gandalf.local.home Cc: stable@vger.kernel.org Acked-by: Christoph Lameter <cl@linux.com> Reported-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de> Tested-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-04-27bpf: fix verifier memory corruptionAlexei Starovoitov
[ Upstream commit c3de6317d748e23b9e46ba36e10483728d00d144 ] Due to missing bounds check the DAG pass of the BPF verifier can corrupt the memory which can cause random crashes during program loading: [8.449451] BUG: unable to handle kernel paging request at ffffffffffffffff [8.451293] IP: [<ffffffff811de33d>] kmem_cache_alloc_trace+0x8d/0x2f0 [8.452329] Oops: 0000 [#1] SMP [8.452329] Call Trace: [8.452329] [<ffffffff8116cc82>] bpf_check+0x852/0x2000 [8.452329] [<ffffffff8116b7e4>] bpf_prog_load+0x1e4/0x310 [8.452329] [<ffffffff811b190f>] ? might_fault+0x5f/0xb0 [8.452329] [<ffffffff8116c206>] SyS_bpf+0x806/0xa30 Fixes: f1bca824dabb ("bpf: add search pruning optimization to verifier") Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-04-24timers/tick/broadcast-hrtimer: Fix suspicious RCU usage in idle loopPreeti U Murthy
[ Upstream commit a127d2bcf1fbc8c8e0b5cf0dab54f7d3ff50ce47 ] The hrtimer mode of broadcast queues hrtimers in the idle entry path so as to wakeup cpus in deep idle states. The associated call graph is : cpuidle_idle_call() |____ clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, ....)) |_____tick_broadcast_set_event() |____clockevents_program_event() |____bc_set_next() The hrtimer_{start/cancel} functions call into tracing which uses RCU. But it is not legal to call into RCU in cpuidle because it is one of the quiescent states. Hence protect this region with RCU_NONIDLE which informs RCU that the cpu is momentarily non-idle. As an aside it is helpful to point out that the clock event device that is programmed here is not a per-cpu clock device; it is a pseudo clock device, used by the broadcast framework alone. The per-cpu clock device programming never goes through bc_set_next(). Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: linuxppc-dev@ozlabs.org Cc: mpe@ellerman.id.au Cc: tglx@linutronix.de Link: http://lkml.kernel.org/r/20150318104705.17763.56668.stgit@preeti.in.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-04-24Revert "PM / hibernate: avoid unsafe pages in e820 reserved regions"Rafael J. Wysocki
[ Upstream commit f82daee49c09cf6a99c28303d93438a2566e5552 ] Commit 84c91b7ae07c (PM / hibernate: avoid unsafe pages in e820 reserved regions) is reported to make resume from hibernation on Lenovo x230 unreliable, so revert it. We will revisit the issue the commit in question was supposed to fix in the future. Link: https://bugzilla.kernel.org/show_bug.cgi?id=96111 Reported-by: rhn <kebuac.rhn@porcupinefactory.org> Cc: 3.17+ <stable@vger.kernel.org> # 3.17+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-04-24sched: Fix RLIMIT_RTTIME when PI-boosting to RTBrian Silverman
[ Upstream commit 746db9443ea57fd9c059f62c4bfbf41cf224fe13 ] When non-realtime tasks get priority-inheritance boosted to a realtime scheduling class, RLIMIT_RTTIME starts to apply to them. However, the counter used for checking this (the same one used for SCHED_RR timeslices) was not getting reset. This meant that tasks running with a non-realtime scheduling class which are repeatedly boosted to a realtime one, but never block while they are running realtime, eventually hit the timeout without ever running for a time over the limit. This patch resets the realtime timeslice counter when un-PI-boosting from an RT to a non-RT scheduling class. I have some test code with two threads and a shared PTHREAD_PRIO_INHERIT mutex which induces priority boosting and spins while boosted that gets killed by a SIGXCPU on non-fixed kernels but doesn't with this patch applied. It happens much faster with a CONFIG_PREEMPT_RT kernel, and does happen eventually with PREEMPT_VOLUNTARY kernels. Signed-off-by: Brian Silverman <brian@peloton-tech.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: austin@peloton-tech.com Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1424305436-6716-1-git-send-email-brian@peloton-tech.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-04-16perf: Fix irq_work 'tail' recursionPeter Zijlstra
[ Upstream commit d525211f9d1be8b523ec7633f080f2116f5ea536 ] Vince reported a watchdog lockup like: [<ffffffff8115e114>] perf_tp_event+0xc4/0x210 [<ffffffff810b4f8a>] perf_trace_lock+0x12a/0x160 [<ffffffff810b7f10>] lock_release+0x130/0x260 [<ffffffff816c7474>] _raw_spin_unlock_irqrestore+0x24/0x40 [<ffffffff8107bb4d>] do_send_sig_info+0x5d/0x80 [<ffffffff811f69df>] send_sigio_to_task+0x12f/0x1a0 [<ffffffff811f71ce>] send_sigio+0xae/0x100 [<ffffffff811f72b7>] kill_fasync+0x97/0xf0 [<ffffffff8115d0b4>] perf_event_wakeup+0xd4/0xf0 [<ffffffff8115d103>] perf_pending_event+0x33/0x60 [<ffffffff8114e3fc>] irq_work_run_list+0x4c/0x80 [<ffffffff8114e448>] irq_work_run+0x18/0x40 [<ffffffff810196af>] smp_trace_irq_work_interrupt+0x3f/0xc0 [<ffffffff816c99bd>] trace_irq_work_interrupt+0x6d/0x80 Which is caused by an irq_work generating new irq_work and therefore not allowing forward progress. This happens because processing the perf irq_work triggers another perf event (tracepoint stuff) which in turn generates an irq_work ad infinitum. Avoid this by raising the recursion counter in the irq_work -- which effectively disables all software events (including tracepoints) from actually triggering again. Reported-by: Vince Weaver <vincent.weaver@maine.edu> Tested-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20150219170311.GH21418@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-04-16sched/wait: Provide infrastructure to deal with nested blockingPeter Zijlstra
[ Upstream commit 61ada528dea028331e99e8ceaed87c683ad25de2 ] There are a few places that call blocking primitives from wait loops, provide infrastructure to support this without the typical task_struct::state collision. We record the wakeup in wait_queue_t::flags which leaves task_struct::state free to be used by others. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: tglx@linutronix.de Cc: ilya.dryomov@inktank.com Cc: umgwanakikbuti@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20140924082242.051202318@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-03-28cpuset: Fix cpuset sched_relax_domain_levelJason Low
[ Upstream commit 283cb41f426b723a0255702b761b0fc5d1b53a81 ] The cpuset.sched_relax_domain_level can control how far we do immediate load balancing on a system. However, it was found on recent kernels that echo'ing a value into cpuset.sched_relax_domain_level did not reduce any immediate load balancing. The reason this occurred was because the update_domain_attr_tree() traversal did not update for the "top_cpuset". This resulted in nothing being changed when modifying the sched_relax_domain_level parameter. This patch is able to address that problem by having update_domain_attr_tree() allow updates for the root in the cpuset traversal. Fixes: fc560a26acce ("cpuset: replace cpuset->stack_list with cpuset_for_each_descendant_pre()") Cc: <stable@vger.kernel.org> # 3.9+ Signed-off-by: Jason Low <jason.low2@hp.com> Signed-off-by: Zefan Li <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> Tested-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-03-28cpuset: fix a warning when clearing configured masks in old hierarchyZefan Li
[ Upstream commit 79063bffc81f82689bd90e16da1b49408f3bf095 ] When we clear cpuset.cpus, cpuset.effective_cpus won't be cleared: # mount -t cgroup -o cpuset xxx /mnt # mkdir /mnt/tmp # echo 0 > /mnt/tmp/cpuset.cpus # echo > /mnt/tmp/cpuset.cpus # cat cpuset.cpus # cat cpuset.effective_cpus 0-15 And a kernel warning in update_cpumasks_hier() is triggered: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 4028 at kernel/cpuset.c:894 update_cpumasks_hier+0x471/0x650() Cc: <stable@vger.kernel.org> # 3.17+ Signed-off-by: Zefan Li <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> Tested-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-03-28cpuset: initialize effective masks when clone_children is enabledZefan Li
[ Upstream commit 790317e1b266c776765a4bdcedefea706ff0fada ] If clone_children is enabled, effective masks won't be initialized due to the bug: # mount -t cgroup -o cpuset xxx /mnt # echo 1 > cgroup.clone_children # mkdir /mnt/tmp # cat /mnt/tmp/ # cat cpuset.effective_cpus # cat cpuset.cpus 0-15 And then this cpuset won't constrain the tasks in it. Either the bug or the fix has no effect on unified hierarchy, as there's no clone_chidren flag there any more. Reported-by: Christian Brauner <christianvanbrauner@gmail.com> Reported-by: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: <stable@vger.kernel.org> # 3.17+ Signed-off-by: Zefan Li <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> Tested-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-03-28workqueue: fix hang involving racing cancel[_delayed]_work_sync()'s for ↵Tejun Heo
PREEMPT_NONE [ Upstream commit 8603e1b30027f943cc9c1eef2b291d42c3347af1 ] cancel[_delayed]_work_sync() are implemented using __cancel_work_timer() which grabs the PENDING bit using try_to_grab_pending() and then flushes the work item with PENDING set to prevent the on-going execution of the work item from requeueing itself. try_to_grab_pending() can always grab PENDING bit without blocking except when someone else is doing the above flushing during cancelation. In that case, try_to_grab_pending() returns -ENOENT. In this case, __cancel_work_timer() currently invokes flush_work(). The assumption is that the completion of the work item is what the other canceling task would be waiting for too and thus waiting for the same condition and retrying should allow forward progress without excessive busy looping Unfortunately, this doesn't work if preemption is disabled or the latter task has real time priority. Let's say task A just got woken up from flush_work() by the completion of the target work item. If, before task A starts executing, task B gets scheduled and invokes __cancel_work_timer() on the same work item, its try_to_grab_pending() will return -ENOENT as the work item is still being canceled by task A and flush_work() will also immediately return false as the work item is no longer executing. This puts task B in a busy loop possibly preventing task A from executing and clearing the canceling state on the work item leading to a hang. task A task B worker executing work __cancel_work_timer() try_to_grab_pending() set work CANCELING flush_work() block for work completion completion, wakes up A __cancel_work_timer() while (forever) { try_to_grab_pending() -ENOENT as work is being canceled flush_work() false as work is no longer executing } This patch removes the possible hang by updating __cancel_work_timer() to explicitly wait for clearing of CANCELING rather than invoking flush_work() after try_to_grab_pending() fails with -ENOENT. Link: http://lkml.kernel.org/g/20150206171156.GA8942@axis.com v3: bit_waitqueue() can't be used for work items defined in vmalloc area. Switched to custom wake function which matches the target work item and exclusive wait and wakeup. v2: v1 used wake_up() on bit_waitqueue() which leads to NULL deref if the target bit waitqueue has wait_bit_queue's on it. Use DEFINE_WAIT_BIT() and __wake_up_bit() instead. Reported by Tomeu Vizoso. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Rabin Vincent <rabin.vincent@axis.com> Cc: Tomeu Vizoso <tomeu.vizoso@gmail.com> Cc: stable@vger.kernel.org Tested-by: Jesper Nilsson <jesper.nilsson@axis.com> Tested-by: Rabin Vincent <rabin.vincent@axis.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-03-28ftrace: Fix ftrace enable ordering of sysctl ftrace_enabledSteven Rostedt (Red Hat)
[ Upstream commit 524a38682573b2e15ab6317ccfe50280441514be ] Some archs (specifically PowerPC), are sensitive with the ordering of the enabling of the calls to function tracing and setting of the function to use to be traced. That is, update_ftrace_function() sets what function the ftrace_caller trampoline should call. Some archs require this to be set before calling ftrace_run_update_code(). Another bug was discovered, that ftrace_startup_sysctl() called ftrace_run_update_code() directly. If the function the ftrace_caller trampoline changes, then it will not be updated. Instead a call to ftrace_startup_enable() should be called because it tests to see if the callback changed since the code was disabled, and will tell the arch to update appropriately. Most archs do not need this notification, but PowerPC does. The problem could be seen by the following commands: # echo 0 > /proc/sys/kernel/ftrace_enabled # echo function > /sys/kernel/debug/tracing/current_tracer # echo 1 > /proc/sys/kernel/ftrace_enabled # cat /sys/kernel/debug/tracing/trace The trace will show that function tracing was not active. Cc: stable@vger.kernel.org # 2.6.27+ Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-03-28ftrace: Fix en(dis)able graph caller when en(dis)abling record via sysctlPratyush Anand
[ Upstream commit 1619dc3f8f555ee1cdd3c75db3885d5715442b12 ] When ftrace is enabled globally through the proc interface, we must check if ftrace_graph_active is set. If it is set, then we should also pass the FTRACE_START_FUNC_RET command to ftrace_run_update_code(). Similarly, when ftrace is disabled globally through the proc interface, we must check if ftrace_graph_active is set. If it is set, then we should also pass the FTRACE_STOP_FUNC_RET command to ftrace_run_update_code(). Consider the following situation. # echo 0 > /proc/sys/kernel/ftrace_enabled After this ftrace_enabled = 0. # echo function_graph > /sys/kernel/debug/tracing/current_tracer Since ftrace_enabled = 0, ftrace_enable_ftrace_graph_caller() is never called. # echo 1 > /proc/sys/kernel/ftrace_enabled Now ftrace_enabled will be set to true, but still ftrace_enable_ftrace_graph_caller() will not be called, which is not desired. Further if we execute the following after this: # echo nop > /sys/kernel/debug/tracing/current_tracer Now since ftrace_enabled is set it will call ftrace_disable_ftrace_graph_caller(), which causes a kernel warning on the ARM platform. On the ARM platform, when ftrace_enable_ftrace_graph_caller() is called, it checks whether the old instruction is a nop or not. If it's not a nop, then it returns an error. If it is a nop then it replaces instruction at that address with a branch to ftrace_graph_caller. ftrace_disable_ftrace_graph_caller() behaves just the opposite. Therefore, if generic ftrace code ever calls either ftrace_enable_ftrace_graph_caller() or ftrace_disable_ftrace_graph_caller() consecutively two times in a row, then it will return an error, which will cause the generic ftrace code to raise a warning. Note, x86 does not have an issue with this because the architecture specific code for ftrace_enable_ftrace_graph_caller() and ftrace_disable_ftrace_graph_caller() does not check the previous state, and calling either of these functions twice in a row has no ill effect. Link: http://lkml.kernel.org/r/e4fbe64cdac0dd0e86a3bf914b0f83c0b419f146.1425666454.git.panand@redhat.com Cc: stable@vger.kernel.org # 2.6.31+ Signed-off-by: Pratyush Anand <panand@redhat.com> [ removed extra if (ftrace_start_up) and defined ftrace_graph_active as 0 if CONFIG_FUNCTION_GRAPH_TRACER is not set. ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-03-28ftrace: Clear REGS_EN and TRAMP_EN flags on disabling record via sysctlSteven Rostedt (Red Hat)
[ Upstream commit b24d443b8f17d9776f5fc1f6c780a0a21eb02913 ] When /proc/sys/kernel/ftrace_enabled is set to zero, all function tracing is disabled. But the records that represent the functions still hold information about the ftrace_ops that are hooked to them. ftrace_ops may request "REGS" (have a full set of pt_regs passed to the callback), or "TRAMP" (the ops has its own trampoline to use). When the record is updated to represent the state of the ops hooked to it, it sets "REGS_EN" and/or "TRAMP_EN" to state that the callback points to the correct trampoline (REGS has its own trampoline). When ftrace_enabled is set to zero, all ftrace locations are a nop, so they do not point to any trampoline. But the _EN flags are still set. This can cause the accounting to go wrong when ftrace_enabled is cleared and an ops that has a trampoline is registered or unregistered. For example, the following will cause ftrace to crash: # echo function_graph > /sys/kernel/debug/tracing/current_tracer # echo 0 > /proc/sys/kernel/ftrace_enabled # echo nop > /sys/kernel/debug/tracing/current_tracer # echo 1 > /proc/sys/kernel/ftrace_enabled # echo function_graph > /sys/kernel/debug/tracing/current_tracer As function_graph uses a trampoline, when ftrace_enabled is set to zero the updates to the record are not done. When enabling function_graph again, the record will still have the TRAMP_EN flag set, and it will look for an op that has a trampoline other than the function_graph ops, and fail to find one. Cc: stable@vger.kernel.org # 3.17+ Reported-by: Pratyush Anand <panand@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-03-28console: Fix console name size mismatchPeter Hurley
commit 30a22c215a0007603ffc08021f2e8b64018517dd upstream. commit 6ae9200f2cab7 ("enlarge console.name") increased the storage for the console name to 16 bytes, but not the corresponding struct console_cmdline::name storage. Console names longer than 8 bytes cause read beyond end-of-string and failure to match console; I'm not sure if there are other unexpected consequences. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> (cherry picked from commit 2cf6258c282608633c9477e5c8e319e948565122)
2015-03-23sched/autogroup: Fix failure to set cpu.rt_runtime_usPeter Zijlstra
commit 1fe89e1b6d270aa0d3452c60d38461ea589594e3 upstream. Because task_group() uses a cache of autogroup_task_group(), whose output depends on sched_class, switching classes can generate problems. In particular, when started as fair, the cache points to the autogroup, so when switching to RT the tg_rt_schedulable() test fails for every cpu.rt_{runtime,period}_us change because now the autogroup has tasks and no runtime. Furthermore, going back to the previous semantics of varying task_group() with sched_class has the down-side that the sched_debug output varies as well, even though the task really is in the autogroup. Therefore add an autogroup exception to tg_has_rt_tasks() -- such that both (all) task_group() usages in sched/core now have one. And remove all the remnants of the variable task_group() output. Reported-by: Zefan Li <lizefan@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Stefan Bader <stefan.bader@canonical.com> Fixes: 8323f26ce342 ("sched: Fix race in task_group()") Link: http://lkml.kernel.org/r/20150209112237.GR5029@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-23sched: Fix hrtick_start() on UPWanpeng Li
commit 868933359a3bdda25b562e9d41bce7071edc1b08 upstream. The commit 177ef2a6315e ("sched/deadline: Fix a precision problem in the microseconds range") forgot to change the UP version of hrtick_start(), do so now. Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> Fixes: 177ef2a6315e ("sched/deadline: Fix a precision problem in the microseconds range") [ Fixed the changelog. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Juri Lelli <juri.lelli@arm.com> Cc: Kirill Tkhai <ktkhai@parallels.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1416962647-76792-7-git-send-email-wanpeng.li@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-23locking/rtmutex: Avoid a NULL pointer dereference on deadlockSebastian Andrzej Siewior
commit 8d1e5a1a1ccf5ae9d8a5a0ee7960202ccb0c5429 upstream. With task_blocks_on_rt_mutex() returning early -EDEADLK we never add the waiter to the waitqueue. Later, we try to remove it via remove_waiter() and go boom in rt_mutex_top_waiter() because rb_entry() gives a NULL pointer. ( Tested on v3.18-RT where rtmutex is used for regular mutex and I tried to get one twice in a row. ) Not sure when this started but I guess 397335f004f4 ("rtmutex: Fix deadlock detector for real") or commit 3d5c9340d194 ("rtmutex: Handle deadlock detection smarter"). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1424187823-19600-1-git-send-email-bigeasy@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-03-14mm, hugetlb: remove unnecessary lower bound on sysctl handlers"?Andrey Ryabinin
commit 3cd7645de624939c38f5124b4ac15f8b35a1a8b7 upstream. Commit ed4d4902ebdd ("mm, hugetlb: remove hugetlb_zero and hugetlb_infinity") replaced 'unsigned long hugetlb_zero' with 'int zero' leading to out-of-bounds access in proc_doulongvec_minmax(). Use '.extra1 = NULL' instead of '.extra1 = &zero'. Passing NULL is equivalent to passing minimal value, which is 0 for unsigned types. Fixes: ed4d4902ebdd ("mm, hugetlb: remove hugetlb_zero and hugetlb_infinity") Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Suggested-by: Manfred Spraul <manfred@colorfullife.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-03-06ntp: Fixup adjtimex freq validation on 32-bit systemsJohn Stultz
commit 29183a70b0b828500816bd794b3fe192fce89f73 upstream. Additional validation of adjtimex freq values to avoid potential multiplication overflows were added in commit 5e5aeb4367b (time: adjtimex: Validate the ADJ_FREQUENCY values) Unfortunately the patch used LONG_MAX/MIN instead of LLONG_MAX/MIN, which was fine on 64-bit systems, but being much smaller on 32-bit systems caused false positives resulting in most direct frequency adjustments to fail w/ EINVAL. ntpd only does direct frequency adjustments at startup, so the issue was not as easily observed there, but other time sync applications like ptpd and chrony were more effected by the bug. See bugs: https://bugzilla.kernel.org/show_bug.cgi?id=92481 https://bugzilla.redhat.com/show_bug.cgi?id=1188074 This patch changes the checks to use LLONG_MAX for clarity, and additionally the checks are disabled on 32-bit systems since LLONG_MAX/PPM_SCALE is always larger then the 32-bit long freq value, so multiplication overflows aren't possible there. Reported-by: Josh Boyer <jwboyer@fedoraproject.org> Reported-by: George Joseph <george.joseph@fairview5.com> Tested-by: George Joseph <george.joseph@fairview5.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sasha Levin <sasha.levin@oracle.com> Link: http://lkml.kernel.org/r/1423553436-29747-1-git-send-email-john.stultz@linaro.org [ Prettified the changelog and the comments a bit. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-06kdb: fix incorrect counts in KDB summary command outputJay Lan
commit 146755923262037fc4c54abc28c04b1103f3cc51 upstream. The output of KDB 'summary' command should report MemTotal, MemFree and Buffers output in kB. Current codes report in unit of pages. A define of K(x) as is defined in the code, but not used. This patch would apply the define to convert the values to kB. Please include me on Cc on replies. I do not subscribe to linux-kernel. Signed-off-by: Jay Lan <jlan@sgi.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-06ring-buffer: Do not wake up a splice waiter when page is not fullSteven Rostedt (Red Hat)
commit 1e0d6714aceb770b04161fbedd7765d0e1fc27bd upstream. When an application connects to the ring buffer via splice, it can only read full pages. Splice does not work with partial pages. If there is not enough data to fill a page, the splice command will either block or return -EAGAIN (if set to nonblock). Code was added where if the page is not full, to just sleep again. The problem is, it will get woken up again on the next event. That is, when something is written into the ring buffer, if there is a waiter it will wake it up. The waiter would then check the buffer, see that it still does not have enough data to fill a page and go back to sleep. To make matters worse, when the waiter goes back to sleep, it could cause another event, which would wake it back up again to see it doesn't have enough data and sleep again. This produces a tremendous overhead and fills the ring buffer with noise. For example, recording sched_switch on an idle system for 10 seconds produces 25,350,475 events!!! Create another wait queue for those waiters wanting full pages. When an event is written, it only wakes up waiters if there's a full page of data. It does not wake up the waiter if the page is not yet full. After this change, recording sched_switch on an idle system for 10 seconds produces only 800 events. Getting rid of 25,349,675 useless events (99.9969% of events!!), is something to take seriously. Cc: Rabin Vincent <rabin@rab.in> Fixes: e30f53aad220 "tracing: Do not busy wait in buffer splice" Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-06tracing: Fix unmapping loop in tracing_mark_writeVikram Mulukutla
commit 7215853e985a4bef1a6c14e00e89dfec84f1e457 upstream. Commit 6edb2a8a385f0cdef51dae37ff23e74d76d8a6ce introduced an array map_pages that contains the addresses returned by kmap_atomic. However, when unmapping those pages, map_pages[0] is unmapped before map_pages[1], breaking the nesting requirement as specified in the documentation for kmap_atomic/kunmap_atomic. This was caught by the highmem debug code present in kunmap_atomic. Fix the loop to do the unmapping properly. Link: http://lkml.kernel.org/r/1418871056-6614-1-git-send-email-markivx@codeaurora.org Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Reported-by: Lime Yang <limey@codeaurora.org> Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>