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2026-10-02Merge tag 'io_uring-7.3-20261002' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull io_uring fixes from Jens Axboe: - Fix a task_work add use-after-free with SQPOLL. The sqpoll thread could pop and complete the last request while io_req_normal_work_add() was still looking at them after the mpscq push. Use the same approach as DEFER_TASKRUN to protect from that, holding an RCU read lock across the add, and have exit wait for an RCU grace period for SQPOLL rings as well. - CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED rings - Mark the source filter table as COW when cloning bpf filters, so registering another filter on the source doesn't modify the shared table in place - Initialize the task context before running the BPF loop - Requeue zcrx multishot receives stopped by a local resource - End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit) * tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring: fix task_work add use-after-free with SQPOLL io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full io_uring/zcrx: requeue multishot receives stopped by a local resource io_uring: initialize task context before running the BPF loop io_uring: zero big_cqe for aux CQEs on CQE32 rings io_uring: fix free entry check for 32b CQEs on CQE32 rings io_uring: only post the dummy skip CQE on CQE_MIXED rings io_uring/bpf_filter: mark source as COW when cloning filters
2026-09-29io_uring: fix task_work add use-after-free with SQPOLLJens Axboe
For SQPOLL, the sqpoll thread runs task_work off its own list and doesn't need to be told about it, so it can pop and complete a request as soon as mpscq_push() has published it. If that was the last request holding the ring alive, io_ring_exit_work() then frees the ctx, stops the thread, and with it the tctx, while io_req_normal_work_add() is still looking at both after the push: BUG: KASAN: slab-use-after-free in io_req_normal_work_add+0x439/0x510 Read of size 4 at addr ff11000000ca0000 by task repro/55 (...) BUG: KASAN: slab-use-after-free in queue_work_on+0x25/0x70 Write of size 8 at addr ff11000000c3bd00 by task repro/55 Hold an RCU read lock across the add, like io_req_local_work_add() already does, and have io_ring_exit_work() wait for a grace period for SQPOLL rings as well before freeing the ctx. Reported-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr> Link: https://lore.kernel.org/io-uring/20260924205056.3759980-2-Jeremy.Jean@oss.cyber.gouv.fr/ Fixes: af5d68f8892f ("io_uring/sqpoll: manage task_work privately") Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-28io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is fulllollipopkit
SOCKET_URING_OP_TX_TIMESTAMP arms an EPOLLERR apoll multishot and, on each error queue edge, posts one 32 byte aux CQE per timestamp skb. Aux CQEs have no overflow backing, so io_uring_cmd_post_mshot_cqe32() fails once the CQ ring is full. The loop then stops, splices the unprocessed skbs back onto sk_error_queue and returns -EAGAIN. -EAGAIN is IOU_RETRY, so the request goes idle until the next poll event. io_arm_apoll() forces EPOLLET and draining the CQ does not re-run the command, so the spliced-back timestamps stay queued until an unrelated later timestamp produces a new edge. End the multishot when a CQE cannot be posted, as multishot poll and recv already do. There is no partial result to report, so complete with -ENOBUFS: no CQ space is left for the timestamp CQEs. This command does not use provided buffers, so the value cannot be confused with a buffer ring running empty. The terminal CQE still reaches userspace because request completions can go to the overflow list. The application sees a CQE without IORING_CQE_F_MORE, which it already has to handle, and the first issue of the re-armed request delivers the queued timestamps. A timestamp that cannot be extracted keeps its current behaviour. This was found with LLM assistance while reviewing io_uring multishot handlers for the pattern behind a RECV_ZC stall reported earlier (see Link), and confirmed with a reproducer on v7.3-rc2 and an A/B run of this patch. Fixes: 9e4ed359b8ef ("io_uring/netcmd: add tx timestamping cmd support") Link: https://lore.kernel.org/all/010001a0cd914529-23df2f94-bbe0-49cd-ae5d-05922356fa12-000000@email.amazonses.com/ Cc: stable@vger.kernel.org Assisted-by: Codex:gpt-6-sol Assisted-by: Claude:claude-opus-5-5 Signed-off-by: lollipopkit <a@lolli.tech> Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/20260927074206.65427-1-a@lolli.tech Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-28io_uring/zcrx: requeue multishot receives stopped by a local resourceJunyuan Feng
A multishot RECV_ZC can go idle with unread TCP data when a receiver-local resource runs out. An empty copy-fallback niov freelist returns -ENOMEM; a full CQ returns -ENOSPC. After partial progress the stop reason is lost: io_zcrx_copy_chunk() and io_zcrx_recv_skb() report the copied bytes, and tcp_read_sock() drops an error from a later call once earlier data was consumed. The edge-triggered request is then not requeued, so it cannot consume the remaining data until another socket event arrives. Record in io_zcrx_recv_skb() when a walk stops before consuming the length it was offered, and requeue if the pass still returned data. The failed chunk is first on the next pass. The resource is usually still exhausted by then, so that pass fails at once and ends the request with an error CQE, which the application must handle by re-arming. The request does not spin, and the stall becomes a visible error. Keep the existing skb limit and SOCK_DONE handling. Fixes: 11ed914bbf94 ("io_uring/zcrx: add io_recvzc request") Fixes: bc57c7d36c4c ("io_uring/zcrx: add copy fallback") Cc: stable@vger.kernel.org Assisted-by: Codex:gpt-6-sol Assisted-by: Claude:claude-opus-5-5 Signed-off-by: Junyuan Feng <a@lollipopkit.com> Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/010001a0cd914529-23df2f94-bbe0-49cd-ae5d-05922356fa12-000000@email.amazonses.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-23io_uring: initialize task context before running the BPF loopYao Kai
Submitting SQEs through an io_uring BPF loop can trigger a NULL pointer dereference in io_submit_sqes(), as shown by the following arm64 report: [ 2049.380301] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 2049.388788] pc : io_submit_sqes+0x48/0x6c4 [ 2049.389153] lr : bpf_io_uring_submit_sqes+0x10/0x1c [ 2049.396310] Call trace: [ 2049.396531] io_submit_sqes+0x48/0x6c4 (P) [ 2049.396893] bpf_io_uring_submit_sqes+0x10/0x1c [ 2049.397293] bpf_prog_1a2a95cb199202b5+0x3c/0x68 [ 2049.397699] bpf__io_uring_bpf_ops_loop_step+0x5c/0x94 [ 2049.398149] io_run_loop+0x70/0x2e4 [ 2049.398461] __arm64_sys_io_uring_enter+0xf0/0x710 [ 2049.398882] invoke_syscall+0x54/0x10c [ 2049.399414] el0_svc_common.constprop.0+0x40/0xe0 [ 2049.399829] do_el0_svc+0x1c/0x28 [ 2049.400125] el0_svc+0x38/0x1d0 [ 2049.400409] el0t_64_sync_handler+0xa0/0xe4 [ 2049.400779] el0t_64_sync+0x198/0x19c io_uring_enter() dispatches to io_run_loop() before reaching the normal submission path's io_uring_add_tctx_node() call. The loop only checks whether the caller is allowed to run task work; it does not initialize current->io_uring or associate the task with the ring. A BPF call to bpf_io_uring_submit_sqes() then reaches io_get_task_refs(), which assumes that current->io_uring is valid. A ring created with IORING_SETUP_R_DISABLED, IORING_SETUP_SINGLE_ISSUER and IORING_SETUP_DEFER_TASKRUN can be enabled by a different task that has never used io_uring. Enabling the ring makes that task the submitter without allocating its io_uring task context. Its first BPF-driven submission of a pending SQE can therefore cause a kernel Oops. Call io_uring_add_tctx_node() in io_run_loop() before invoking the loop and propagate any initialization error. Do this before acquiring uring_lock, since task context setup may acquire the same mutex. This also establishes the task-to-ring association used for cancellation. Fixes: 033af2b3eb19 ("io_uring: introduce callback driven main loop") Signed-off-by: Yao Kai <yaokai34@huawei.com> Link: https://patch.msgid.link/20260923014310.591292-1-yaokai34@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-21io_uring: zero big_cqe for aux CQEs on CQE32 ringsHui Peng
io_fill_cqe_aux() only clears big_cqe if cqe32 is set, which is only the case for CQE_MIXED. On a CQE32 ring every CQE is 32b, and the extra 16b are left holding whatever was in that slot before. Clear it for CQE32 rings as well, like it was before CQE_MIXED support was added. Fixes: e26dca67fde1 ("io_uring: add support for IORING_SETUP_CQE_MIXED") Assisted-by: LLM Signed-off-by: Hui Peng <benquike@gmail.com> Link: https://patch.msgid.link/20260919203516.2581409-1-benquike@gmail.com [axboe: split from Hui's original patch, edited commit message] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-21io_uring: fix free entry check for 32b CQEs on CQE32 ringsHui Peng
On CQE32 rings, len is in units of 32b CQEs when io_cqe_cache_refill() checks for free entries, so requiring cqe32 + 1 of them means insisting on 2 free CQEs where 1 is enough, and a ring with a single free entry needlessly goes to overflow. Check for a free CQE directly in that case, and keep the cqe32 + 1 check for CQE_MIXED where the units are 16b. Fixes: e26dca67fde1 ("io_uring: add support for IORING_SETUP_CQE_MIXED") Assisted-by: LLM Signed-off-by: Hui Peng <benquike@gmail.com> Link: https://patch.msgid.link/20260919203516.2581409-1-benquike@gmail.com [axboe: split from Hui's original patch, edited commit message] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-21io_uring: only post the dummy skip CQE on CQE_MIXED ringsHui Peng
io_cqe_cache_refill() posts a dummy skip CQE when a 32b CQE would straddle the end of the ring, so the real one can start at offset 0. That only makes sense on CQE_MIXED rings, where slots are 16b and a 32b CQE needs two of them back to back. On a CQE32 ring every slot is already 32b, but io_fill_cqe_aux32() still passes cqe32 == true, and the dummy then gets written at cqes[off] rather than cqes[off << 1], inside another CQE. Limit the dummy to CQE_MIXED rings. Fixes: e26dca67fde1 ("io_uring: add support for IORING_SETUP_CQE_MIXED") Assisted-by: LLM Signed-off-by: Hui Peng <benquike@gmail.com> Link: https://patch.msgid.link/20260919203516.2581409-1-benquike@gmail.com [axboe: split from Hui's original patch, edited commit message] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-21io_uring/bpf_filter: mark source as COW when cloning filtersHui Peng
io_bpf_filter_clone() shares the filter table between source and destination and marks the destination as needing a copy before it can be modified, but leaves the source as is. Registering another filter on the source then modifies the shared table in place, and the change shows up in everything that cloned it. Mark the source as COW as well. Fixes: ed82f35b926b ("io_uring: allow registration of per-task restrictions") Assisted-by: LLM Signed-off-by: Hui Peng <benquike@gmail.com> Link: https://patch.msgid.link/20260919112523.3872581-1-benquike@gmail.com [axboe: edited patch and commit message] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-11Merge tag 'io_uring-7.3-20260911' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull io_uring fixes from Jens Axboe: - Fix a deadlock in the write path with superblock freezing - Fix an issue where a provided buffer ring would overconsume when using MSG_TRUNC - Keep the CQE flags on iopoll requests when adding kbuf flags * tag 'io_uring-7.3-20260911' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring/rw: keep CQE flags on iopoll requests when adding kbuf flags io_uring/net: don't overconsume buffers when using MSG_TRUNC io_uring/net: let io_recv_buf_select return the length of the buffer region io_uring/rw: end write accounting from ->ki_complete
2026-09-09io_uring/rw: keep CQE flags on iopoll requests when adding kbuf flagsCaleb Sander Mateos
io_do_iopoll() assigns the result of io_put_kbuf() to the request's CQE flags upon completion. This overwrites any CQE flags that may have been set by the opcode-specific layer. (For example, if __io_uring_cmd_done() had set IORING_CQE_F_32, it would be cleared.) Switch the = to an |= so the kbuf flags are added to the existing CQE flags rather than replacing them. io_req_rw_complete() does the same with the io_put_kbuf() result. Fixes: e26dca67fde1 ("io_uring: add support for IORING_SETUP_CQE_MIXED") Reported-by: sashiko-bot@kernel.org Link: https://sashiko.dev/#/message/20260827191705.D53C91F000E9%40smtp.kernel.org Signed-off-by: Caleb Sander Mateos <csander@purestorage.com> Reviewed-by: Anuj Gupta <anuj20.g@samsung.com> Link: https://patch.msgid.link/20260902210200.2336720-1-csander@purestorage.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-09io_uring/net: don't overconsume buffers when using MSG_TRUNCGabriel Krisman Bertazi
When a recv/recvmsg is issued with MSG_TRUNC and the incoming packet is larger than the provided buffer, the net layer returns the full length of the packet rather than the number of bytes actually copied into the buffer. As a result, io_uring advances more of the provided buffer ring than was actually filled. Use the actual filled region size to consume the buffer, but still return the full size to preserve MSG_TRUNC semantics. Take care with multishot, because that seems to already truncate the consumption based on the available payload size. This was reported in https://github.com/axboe/liburing/issues/1619. Fixes: ae98dbf43d75 ("io_uring/kbuf: add support for incremental buffer consumption") Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260728191454.1850326-1-krisman@suse.de Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de> Link: https://patch.msgid.link/20260902230041.1320658-3-krisman@suse.de [axboe: fold in size_t unsigned fix] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-08io_uring/net: let io_recv_buf_select return the length of the buffer regionGabriel Krisman Bertazi
In preparation to using this field as an upper limit to truncation, return the size of the allocated region. Fixes: ae98dbf43d75 ("io_uring/kbuf: add support for incremental buffer consumption") Cc: stable@vger.kernel.org Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de> Link: https://patch.msgid.link/20260902230041.1320658-2-krisman@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-08io_uring/rw: end write accounting from ->ki_completeJens Axboe
Commit b000145e9907 moved both the fsnotify calls and the write accounting out of the kiocb completion handler and into the io_req_rw_complete() task_work. However, only the fsnotify part actually needed to move as it may sleep. Ending the write accounting is just a percpu_up_read() on the superblock writers sem. Deferring it is a problem, because it makes dropping SB_FREEZE_WRITE protection depend on the ring owner getting to running task_work. But the task may be blocked in freeze_super(), causing it to never get to that: task io-wq worker -------------------------------------------------------------- io_write() io_kiocb_start_write() (takes sb_writers, hidden from lockdep by __sb_writers_release) write_iter() -> -EIOCBQUEUED ioctl(FS_IOC_SHUTDOWN) bdev_freeze() freeze_super() percpu_down_write() <- waits for the reader above io_write() kiocb_start_write() percpu_down_read() <- queued behind the writer <bio completes> io_complete_rw() queues io_req_rw_complete() <- never runs, task is in D state End the write from io_complete_rw() instead, and leave only the fsnotify calls in task_work. Reported-by: syzbot+2eb3d983669d3e49d4fa@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Fixes: b000145e9907 ("io_uring/rw: defer fsnotify calls to task context") Signed-off-by: Jens Axboe <axboe@kernel.dk>
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>
2026-08-28Merge tag 'io_uring-7.3-20260828' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull io_uring fixes from Jens Axboe: "A few smaller fixes for io_uring that should go into the 7.3-rc1 kernel, all three headed to stable as well. This contains: - A few fixes around cancellation and teardown for waitid - Cap the user size for the query interface copy-out" * tag 'io_uring-7.3-20260828' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring/waitid: avoid siginfo copy during ring teardown io_uring/waitid: honor task_work cancellation io_uring/query: cap user size passed to copy_struct_to_user
2026-08-25io_uring/waitid: avoid siginfo copy during ring teardownHui Su
During ring teardown, io_ring_exit_work() cancels outstanding requests from a kworker with a NULL tctx. The waitid cancellation path eventually reaches io_waitid_finish(), which copies the stored siginfo to the userspace pointer supplied with the request. Ring-wide teardown does not run in the task context that submitted the request, so it must not access that task's userspace pointer. Depending on the address and mm state, the copy may fail with -EFAULT, but the uaccess itself is inappropriate from the teardown kworker. Use a no-copy cancellation callback when io_waitid_remove_all() is called without an owning task context. Complete the request with -ECANCELED while releasing the waitid state without touching siginfo. Keep the existing siginfo handling for explicit async cancellation and task-scoped cancellation. Fixes: f31ecf671ddc ("io_uring: add IORING_OP_WAITID support") Cc: stable@vger.kernel.org Signed-off-by: Hui Su <sh_def@163.com> Link: https://patch.msgid.link/20260818103336.1922818-3-sh_def@163.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-25io_uring/waitid: honor task_work cancellationHui Su
io_waitid_cb() may run through the fallback task_work path when task_work_add() can no longer queue work to the originating task. The fallback runs from a kworker and io_uring marks such task work as canceled through tw.cancel. io_waitid_cb() currently ignores tw.cancel and calls __do_wait(). waitid is task-context dependent: __do_wait() performs child lookup relative to current, and the retry path also uses current->signal->wait_chldexit. If the callback runs from the fallback kworker, current is therefore not the task that submitted the request. Honor tw.cancel before entering __do_wait(). Complete the request with -ECANCELED and skip the siginfo copy, since canceled task work may run without the submitting task's userspace execution context. Keep the existing siginfo handling for normal waitid completion and explicit cancellation. Fixes: f31ecf671ddc ("io_uring: add IORING_OP_WAITID support") Cc: stable@vger.kernel.org Signed-off-by: Hui Su <sh_def@163.com> Link: https://patch.msgid.link/20260818103336.1922818-2-sh_def@163.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-25io_uring/query: cap user size passed to copy_struct_to_userLaxman Acharya Padhya
io_handle_query_entry() clamps hdr.size for the inbound copy_from_user() but keeps the original user value as usize. copy_struct_to_user() uses that usize and, when it is larger than the kernel result, clear_user()s the trailing bytes. As hdr.size is a __u32, a query can request nearly 4 GiB of zeroing, including on the error path where res_size stays 0. The interface is reachable without a ring via IORING_REGISTER_QUERY. Reject sizes larger than PAGE_SIZE, as recommended for copy_struct_* interfaces. Fixes: c265ae75f900 ("io_uring: introduce io_uring querying") Cc: stable@vger.kernel.org # 6.18+ Signed-off-by: Laxman Acharya Padhya <acharyalaxman8848@gmail.com> Reviewed-by: Gabriel Krisman Bertazi <krisman@suse.de> Link: https://patch.msgid.link/20260821103317.91437-1-acharyalaxman8848@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-25Merge tag 'fuse-update-7.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Improve performance of the io-uring transport by introducing buffer pools and zero-copy (Joanne) - Fix lots of bugs (Baokun Li) - Fix io-uring initialization issues (Joanne, Bernd) - More prep work for large folios (Joanne) - Don't limit buffered read to 128k (Jim Harris) - Fix zeroing of page end (dirtied with mmap) on file size extension (Jimmy Zuber) - Improve performance in certain cases with wake_up_sync() when queuing request (Xuewen Yan) - Misc fixes and cleanups (Xuewen Yan) * tag 'fuse-update-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (35 commits) fuse: zero the partial EOF page when extending a file io_uring: Add missing include for ITER_SOURCE and ITER_DEST fuse: Fix the condition to enable over-io-uring fuse: invalidate the correct range after O_APPEND direct write selftests/fuse: test post-EOF page zeroing when a file is extended fuse: wake one waiter per freed slot when raising max_background fuse: use min_not_zero() in fuse_init_server_timeout() fuse: copy request headers via a stack buffer for io-uring fuse: give wakeup hints to the scheduler for synchronous requests fuse: check for NULL root inode in fuse_fill_super_submount fuse: reject a duplicate fd= mount option cuse: wait for pending RCU callbacks on module exit fuse: fix invalidate lock leak on open O_TRUNC DAX failure fuse: fix invalidate lock leak on setattr writeback failure fuse: wait for FR_FINISHED on abort_on_kill to prevent use-after-free fuse: make dentry_tree_work static docs: fuse: document io-uring buffer pool and zero-copy uapi fuse: add zero-copy over io-uring fuse: support registered buffer pools in io-uring fuse: add io-uring buffer pools ...
2026-08-20Merge tag 'for-7.3/block-20260819' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull block updates from Jens Axboe: - NVMe updates via Keith: - Enable Clang context analysis for the nvme host driver, adding context annotations across core, fabrics, rdma, tcp and pci - nvmet reservation state exposed through a new namespace-level debugfs directory, plus ABI documentation for the host sysfs and target configfs interfaces - nvme-tcp host memory disclosure fixes on the read path: reject a read that transferred too few bytes, don't accept C2HData based on blk_rq_payload_bytes() alone, and fix the R2T case for a read command - Parallelize nvme-rdma I/O queue allocation and startup (Surabhi) - Apple nvme fixes and quirks: page aligned admin queue buffers, destroy the admin queue on removal, and various DMA/NVMMU correctness fixes - A large pile of nvmet and host fixes for out-of-bounds reads, refcount/resource leaks, and NULL derefs across auth, zns, passthru, pci-epf, rdma and configfs - Various other fixes and cleanups - MD updates via Yu Kuai: - llbitmap reshape support, the large series wiring exact bitmap mapping and reshape lifecycle through raid5 and raid10, growing the page cache in place, and remapping checkpointed bits as reshape progresses - raid5 fixes for lockless max_nr_stripes and recovery_offset accesses, a reshape deadlock with more failed devices than max degraded, and bitmap batch counter consistency - Atomic write handling for raid1/raid10, and removal of the REQ_NOWAIT support from raid1/10/456 - raid5-ppl use-after-free fix in ppl_do_flush() - A batch of smaller fixes across md core and the bitmap code - s390/dasd ESE full-track write support and the surrounding infrastructure, plus enabling CONTEXT_ANALYSIS for s390/block - RWF_DONTCACHE support for block devices, built on new task-context bio completion infrastructure, and wiring it up for the iomap and buffer dropbehind writeback paths - Async io_uring zone reset all, plus zone management command cleanups allowing REQ_NOWAIT and tightening conventional zone rejection - Block integrity refactoring: lift BIP_CHECK_FLAGS to the shared header, handle nogenerate/noverify properly in fs-integrity, and drop the blk-integrity.h include from bdev.c - Split out a new blk_plug.h header - ublk improvements: add UBLK_F_IO_DESC_SIZE, split request validation from io_desc init, reject non-power-of-2 zone sizes in SET_PARAMS, and a series of hardening fixes around map/unmap and auto buf reg - null_blk cleanups and configfs serialization fixes - nbd queue freeze removal on the setup paths, and a new pre_defined_connections module parameter for pre-created devices - blk-cgroup fixes for the race between policy activation and blkg destruction, and accounting per-cpu stats over possible CPUs across blk-stat, iolatency, iocost and kyber - Various dio fixes: leak on metadata mapping error, validate user space vectors during extraction, and set dma_alignment from the backing file for loop and zloop direct I/O - bio cleanups - Various other fixes and cleanups all over * tag 'for-7.3/block-20260819' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (241 commits) nbd: add pre_defined_connections module parameter for pre-created devices nbd: remove queue freeze for newly created nbd from netlink path nbd: factor out a nbd_genl_foreach_sock nbd: skip queue freeze when setting size at device startup nbd: remove queue freeze in nbd_add_socket nbd: clear queue limits on disconnect nbd: disallow NBD_SET_SOCK on an active device nbd: simplify find_fallback() by removing redundant logic blk-mq: add missing call to srcu_barrier() in blk_mq_free_tag_set() block: mtip32xx: synchronize ioctls with device removal ublk: avoid teardown retry loop on xarray allocation failure null_blk: fix UBSAN shift-out-of-bounds when zone_size is 0 or overflows block: don't include blk-integrity.h in bdev.c xfs: avoid double deferrals for RWF_DONTCACHE writes loop: Fix recently introduced lock inversion block: set QUEUE_FLAG_DYING unconditionally in blk_mark_disk_dead() swim3: Add missing MODULE_DESCRIPTION selftests: ublk: add SET_PARAMS validation test selftests: ublk: add helper for SET_PARAMS ublk: reject non-power-of-2 zone sizes in SET_PARAMS ...
2026-08-20Merge tag 'for-7.3/io_uring-20260819' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull io_uring update from Jens Axboe: "On top of the usual cleanups and fixes, the bigger items in here are: - zcrx work, most of it centered around adding dynamic area provisioning, plus a bunch of prep and cleanups leading up to it: scale refilling with large pages, coalesce same-niov RQEs on refill, separate the RQ head/tail cache lines and cache the RQ tail, and rework the area creation locking. - Fix the futex inflight accounting so that only private futex waits are marked inflight, and don't mark wake requests as inflight at all. - Drop the custom iov copy in the buffer select prep and msg header copy paths, using the generic helpers instead. - Fix a folio size overflow in io_vec_fill_bvec(), and account the pages a compound region really uses in the memmap path. - Fix an iovec leak in uring_cmd when the async cmd isn't recycled, skip the blocking task work for io_uring_cmd_issue_blocking(), and don't skip completion for a synchronous multishot cmd - Defer eventfd signaling when queued from a wakeup handler - Fix io-wq worker accounting when canceling creation callbacks - Annotate remote tasks for kcoverage" * tag 'for-7.3/io_uring-20260819' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (30 commits) io_uring: Add missing include for ITER_SOURCE and ITER_DEST io_uring/uring_cmd: don't skip completion for a synchronous multishot cmd io_uring/memmap: account the pages a compound region really uses io_uring/zcrx: add dynamic area provisioning io_uring/zcrx: lock area creation with pp_lock io_uring/zcrx: keep array of areas io_uring/zcrx: move freelist lock to struct zcrx io_uring/zcrx: unmap under netdev lock io_uring/zcrx: split dmabuf unmap and release io_uring/zcrx: don't pass ifq_reg to area creation io_uring/zcrx: add helper for deriving area token io_uring/zcrx: don't reload skb_shinfo io_urint/zcrx: narrow var scope in io_zcrx_recv_skb() io_uring/zcrx: constify area_reg on import io_uring/zcrx: coalesce same-niov RQEs on refill io_uring/zcrx: cache RQ tail io_uring/zcrx: add RQ iterator io_uring/zcrx: move RQ head/tail to separate cache lines io_uring/zcrx: scale refilling with large pages io_uring/io-wq: fix worker accounting when canceling creation callbacks ...
2026-08-17io_uring/rsrc: rename and export IO_IMU_DEST / IO_IMU_SOURCEJoanne Koong
Rename IO_IMU_DEST and IO_IMU_SOURCE to IO_BUF_DEST and IO_BUF_SOURCE and export it so subsystems may use it. This is needed by the io_buffer_register_bvec() path for callers who may need the buffer to be both readable and writable. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://patch.msgid.link/20260612184840.4058966-5-joannelkoong@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2026-08-17io_uring/rsrc: add io_buffer_register_bvec()Joanne Koong
Add io_buffer_register_bvec() for registering a bvec array. This is a preparatory patch for fuse-over-io-uring zero-copy. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Reviewed-by: Caleb Sander Mateos <csander@purestorage.com> Link: https://patch.msgid.link/20260612184840.4058966-4-joannelkoong@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2026-08-17io_uring/rsrc: split io_buffer_register_request() logicJoanne Koong
Split the main initialization logic in io_buffer_register_request() into a helper function. This is a preparatory patch for supporting kernel-populated buffers in fuse io-uring, which will be reusing this logic. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Reviewed-by: Caleb Sander Mateos <csander@purestorage.com> Link: https://patch.msgid.link/20260612184840.4058966-3-joannelkoong@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2026-08-17io_uring/rsrc: rename io_buffer_register_bvec()/io_buffer_unregister_bvec()Joanne Koong
Currently, io_buffer_register_bvec() takes in a request. In preparation for supporting kernel-populated buffers in fuse io-uring (which will need to register bvecs directly, not through a struct request), rename this to io_buffer_register_request(). A subsequent patch will commandeer the "io_buffer_register_bvec()" function name to support registering bvecs directly. Rename io_buffer_unregister_bvec() to a more generic name, io_buffer_unregister(), as both io_buffer_register_request() and io_buffer_register_bvec() callers will use it for unregistration. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Reviewed-by: Caleb Sander Mateos <csander@purestorage.com> Link: https://patch.msgid.link/20260612184840.4058966-2-joannelkoong@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2026-08-15io_uring/uring_cmd: don't skip completion for a synchronous multishot cmdJens Axboe
If IORING_URING_CMD_MULTISHOT is set, io_uring_cmd() treats any non-negative return from ->uring_cmd() as the driver having taken ownership of the request and returns IOU_ISSUE_SKIP_COMPLETE. But nothing guarantees that the driver did so, and any handler that just completes the command inline and returns 0 or a positive result then leaves the request orphaned, leaking the io_kiocb, the async data, and the file reference. The special case isn't needed. ublk returns -EIOCBQUEUED for the multishot fetch command, which is passed through as-is, and the poll driven socket timestamp command returns -EAGAIN. Kill it, a multishot handler that wants to hang on to the request must return -EIOCBQUEUED or -EAGAIN like any other command. Fixes: 620a50c92700 ("io_uring: uring_cmd: add multishot support") Cc: stable@vger.kernel.org Reported-by: syzbot+a4ccdd7ebf452e4d4701@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/6a7a0194.b50370da.49fe0.0056.GAE@google.com/ Link: https://lore.kernel.org/all/20260811115125.1831170-1-vasilisalmpanis@gmail.com/ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/memmap: account the pages a compound region really usesAli Ahmet Memis
io_mem_alloc_compound() allocates get_order(size) pages, which rounds a region size that is not a power of two up to the next order. The pages past the region are part of the same allocation and cannot be used for anything else, but io_create_region() accounts reg->size >> PAGE_SHIFT, so they are never charged against RLIMIT_MEMLOCK. For a ring with 4096 SQ entries and the default CQ size the region is 37 pages while the allocation is 64. Account the tail pages together with the region, and fall back to the exact sized bulk allocation when they do not fit the limit, so a user close to their limit still gets the region rather than an error. io_free_region() gives the same amount back, the compound case being the one that set IO_REGION_F_SINGLE_REF. Counting how many 4096 entry rings an unprivileged user can create under a given RLIMIT_MEMLOCK, before and after: limit (pages) before after 256 2 2 300 2 2 350 3 2 400 3 3 512 5 4 Five rings under a 512 page limit really pin 640 pages. Fixes: dfbbfbf19187 ("io_uring: introduce concept of memory regions") Link: https://lore.kernel.org/all/87ik5ncj8d.fsf@mailhost.krisman.be/ Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com> Link: https://patch.msgid.link/20260806180044.275543-1-ali@iusegentoo.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: add dynamic area provisioningPavel Begunkov
It's not always possible for the user to predict during registration how much memory zcrx will need to sustain the traffic. Allow to dynamically add more areas with a new ctrl code ZCRX_CTRL_ADD_AREA. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/43495ca686713b3f0014c9f47c4c0276d704da4d.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: lock area creation with pp_lockPavel Begunkov
Protect __zcrx_create_area() with pp_lock. It's not needed for now, nobody can take the lock in parallel, but we'll need it for dynamic area creation for avoiding races with the device dying. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/a667399971120227a28d54ebabc50e707f717bf3.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: keep array of areasPavel Begunkov
Currently, we have only a one area per zcrx instance, and struct io_zcrx_ifq stores a single pointer. To prepare for adding more areas, replace it with an array of areas. We'll be creating them at runtime, and the array is protected by 3 locks: ->pp_lock, ->alloc_lock and ->rq.lock. It takes all of them when switching arrays, and readers should hold either of them. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/d186adfa0ea26f651804cffef77d477f257eb404.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: move freelist lock to struct zcrxPavel Begunkov
freelist_lock, which protects slow path allocations, is currently stored in struct io_zcrx_area. Once we add support for multiple queues, we'll need a lock in the zcrx ctx, move it there. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/be7feadff1e210861433f99fe44170aa27ec5b33.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: unmap under netdev lockPavel Begunkov
Make sure we unmap areas while closing a queue. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/1c41f349f8bcbcaafb17a9c81d4157aa9d30de93.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: split dmabuf unmap and releasePavel Begunkov
Until now unmapping and destroying dmabuf were the same thing. To keep it consistent with non-dmabuf, split it into two separate helpers. Unmap destroys mappings and attachements as it should, and release only putting down the dmabuf fd reference. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/bd8c1fd8dac85ce0cf839b389ecd6050761965ca.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: don't pass ifq_reg to area creationPavel Begunkov
We might want to create an area without having an instance of struct io_uring_zcrx_ifq_reg. Extract a helper that doesn't have the ifq registration structure as an argument but takes the buf length explicitly. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/76751ee4747abb4893058fcaaa36895dfe24a297.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: add helper for deriving area tokenPavel Begunkov
Add zcrx_area_id_to_token() to deduplicate the way the area token is calculated out of the area index. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/c7752161065a1f7273ce3de9683804dd105c6d53.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: don't reload skb_shinfoPavel Begunkov
Keep skb_shinfo in a local variable so that it doesn't reload it on every iteration of the loop. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/1e4c864a5ea639803c866aea70b8d5bf558f189f.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_urint/zcrx: narrow var scope in io_zcrx_recv_skb()Pavel Begunkov
A preparation patch that limits scopes of a couple variables in io_zcrx_recv_skb() and rename them, it makes it easier to reason about the code. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/182c140502e7be534caf10360714a4d78f2ce5f4.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: constify area_reg on importPavel Begunkov
io_import_area() doesn't modify its struct io_uring_zcrx_area_reg argument, add const to enforce that, it'll make later modifications easier. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/2cd4a3e43875576587c900ebdf8f1fb4af266e4a.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: coalesce same-niov RQEs on refillPavel Begunkov
With large rx piages I often see >10 sequential RQEs referring to the same niov. Instead of putting them one by one, count such RQEs during parsing and batch refcounting for the niov. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/71f11d5de47553f187737e0e892ab783b03f53b1.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: cache RQ tailPavel Begunkov
The RQ tail is updated by the user space. Cache it to reduce cache line bouncing. Refilling now tries to exhaust the previous batch of rqes, but since it could be too low, the iterator is allowed to recalculate the rqes to process once after synching the tail value. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/b42d2ed8b0e697110b646573b5da2a5f8e85f92e.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: add RQ iteratorPavel Begunkov
Add a iterator structure and helper functions for the refill queue processing to avoid polluting io_zcrx_ring_refill() with extra state and logic once it's extended in following patches. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/5d2933ea7bcf9c19c44e43afb3638d7afb362b3c.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: move RQ head/tail to separate cache linesPavel Begunkov
RQ head and tail are currently put into the same cache line, which can cause false sharing problems when refill is run on another CPU. Put them into separate cache lines. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Mina Almasry <almasrymina@google.com> Link: https://patch.msgid.link/f769116a3f5267f06cb9a9a819d482ddea2e0852.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/zcrx: scale refilling with large pagesPavel Begunkov
io_zcrx_ring_refill() caps the loop by mixing the max number of allocated netmems and the number of available RQEs together, which caps the number of entries to process the pp cache size. As a result, when niovs are heavily fragmented, the refilling logic allocates only a small number of niovs per call on average and sometimes even none. Keep a separate counter for the number of processed RQ entries, which is capped by a roughly calculated from the page size value to keep the cache full. And separately break if it allocates enough niovs. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/143cf439299728759eb0a840c866363fe99293f0.1786108672.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/io-wq: fix worker accounting when canceling creation callbacksVishnu Razdan
create_worker_cb() reserves an io-wq worker slot only after its task-work callback runs. If the callback is canceled before then, io_worker_cancel_cb() still decrements acct->nr_workers. When an existing worker retires with its creation callback pending, that worker has already decremented the same account's worker count. The resulting undercount permits worker creation beyond the account's configured limit. On an AST2600 OpenBMC system, an unchanged sensor daemon reached 4,291 threads with the original kernel. With an equivalent downstream fix, 25 passive samples under its normal workload showed 6-9 threads. Decrement nr_workers only when the canceled callback is not create_worker_cb(). Continuation callbacks still release their reserved slot, and both callback types retain the existing running-count, reference-count, and create-state cleanup. Fixes: 1d5f5ea7cb7d ("io-wq: remove worker to owner tw dependency") Cc: stable@vger.kernel.org Assisted-by: Codex:gpt-5.6-sol Signed-off-by: Vishnu Razdan <vrazdan@openai.com> Reviewed-by: Gabriel Krisman Bertazi <krisman@suse.de> Link: https://patch.msgid.link/20260811-vrazdan-io-wq-b4-submit-v1-1-719ced16c921@openai.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/net: Drop ddir argument from io_msg_copy_hdrGabriel Krisman Bertazi
ddir was only ever forwarded to io_compat_msg_copy_hdr, which never looked at it. Drop it. Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de> Link: https://patch.msgid.link/20260813004022.3514537-4-krisman@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/net: Drop custom iov copy in io_msg_copy_hdrGabriel Krisman Bertazi
Similar to commit f4eaf8eda89e ("io_uring/rsrc: Drop io_copy_iov in favor of iovec API"), avoid the custom copy of a single iovec and just rely on the iovec api. This lets the compat and native paths share the buffer-select length lookup Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de> Link: https://patch.msgid.link/20260813004022.3514537-3-krisman@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/rw: Drop custom iov copy in io_iov_buffer_select_prepGabriel Krisman Bertazi
Similar to commit f4eaf8eda89e ("io_uring/rsrc: Drop io_copy_iov in favor of iovec API"), avoid custom copy and just rely on the iovec api. Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de> Link: https://patch.msgid.link/20260813004022.3514537-2-krisman@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring: defer eventfd signaling when queued from a wakeup handlerJens Axboe
io_req_local_work_add() signals the CQ ring eventfd inline when it is the one to push the first entry onto ->work_list. For DEFER_TASKRUN rings that add is frequently done from a waitqueue wakeup handler, where an arbitrary waitqueue lock is held. eventfd_signal_mask() only refuses to recurse when current->in_eventfd is set, but that bit is set by eventfd_signal_mask() itself. If the wake chain starts somewhere else, signal goes out inline and can feed back into epoll. Add IOU_F_TWQ_IN_WAKE, set it on the task_work add done from the three waitqueue callbacks, and use it to force io_eventfd_signal() down the existing call_rcu_hurry() deferral instead of signaling inline. Fixes: 21a091b970cd ("io_uring: signal registered eventfd to process deferred task work") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20260813133843.2933127-1-4ncienth@gmail.com/ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-12io_uring/rsrc: reject overflowing regvec bvec byte countsJérémy Jean
io_import_reg_vec() converts the estimated number of bio_vec entries into iovec-sized storage when struct bio_vec is larger than struct iovec. The conversion still multiplies nr_segs by sizeof(struct bio_vec) in size_t without checking for overflow. On 32-bit kernels, a registered buffer large enough to make io_estimate_bvec_size() return 357913942 segments wraps the byte count from 0x100000008 to 8. io_vec_realloc() then reserves only the input iovecs plus one extra slot while io_vec_fill_bvec() writes the full bio_vec array. Check both the multiplication and the rounding addition before deriving the replacement iovec count. Fixes: b4e41050b212 ("io_uring/rsrc: raise registered buffer 1GB limit") Assisted-by: Codex:gpt-5 Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr> Link: https://patch.msgid.link/20260812203042.720348-1-Jeremy.Jean@oss.cyber.gouv.fr Signed-off-by: Jens Axboe <axboe@kernel.dk>