linux/io_uring
Gabriel Krisman Bertazi 068c27e32e io-wq: write next_work before dropping acct_lock
Commit 361aee450c ("io-wq: add intermediate work step between pending
list and active work") closed a race between a cancellation and the work
being removed from the wq for execution.  To ensure the request is
always reachable by the cancellation, we need to move it within the wq
lock, which also synchronizes the cancellation.  But commit
42abc95f05 ("io-wq: decouple work_list protection from the big
wqe->lock") replaced the wq lock here and accidentally reintroduced the
race by releasing the acct_lock too early.

In other words:

        worker                |     cancellation
work = io_get_next_work()     |
raw_spin_unlock(&acct->lock); |
			      |
                              | io_acct_cancel_pending_work
                              | io_wq_worker_cancel()
worker->next_work = work

Using acct_lock is still enough since we synchronize on it on
io_acct_cancel_pending_work.

Fixes: 42abc95f05 ("io-wq: decouple work_list protection from the big wqe->lock")
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://lore.kernel.org/r/20240416021054.3940-2-krisman@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-17 08:20:32 -06:00
..
advise.c io_uring: always go async for unsupported fadvise flags 2023-01-29 15:18:26 -07:00
advise.h
alloc_cache.h io_uring/alloc_cache: switch to array based caching 2024-04-15 08:10:25 -06:00
cancel.c io_uring: fix warnings on shadow variables 2024-04-15 08:10:26 -06:00
cancel.h io_uring/cancel: don't default to setting req->work.cancel_seq 2024-02-08 13:27:06 -07:00
epoll.c io_uring: undeprecate epoll_ctl support 2023-05-26 20:22:41 -06:00
epoll.h
fdinfo.c io_uring: fix warnings on shadow variables 2024-04-15 08:10:26 -06:00
fdinfo.h
filetable.c io_uring: drop any code related to SCM_RIGHTS 2023-12-19 12:36:34 -07:00
filetable.h io_uring: expand main struct io_kiocb flags to 64-bits 2024-02-08 13:27:03 -07:00
fs.c io_uring/fs: consider link->flags when getting path for LINKAT 2023-11-20 09:01:42 -07:00
fs.h
futex.c io_uring/alloc_cache: switch to array based caching 2024-04-15 08:10:25 -06:00
futex.h io_uring/alloc_cache: switch to array based caching 2024-04-15 08:10:25 -06:00
io-wq.c io-wq: write next_work before dropping acct_lock 2024-04-17 08:20:32 -06:00
io-wq.h io_uring: break out of iowq iopoll on teardown 2023-09-07 09:02:27 -06:00
io_uring.c io_uring: ensure overflow entries are dropped when ring is exiting 2024-04-15 08:10:27 -06:00
io_uring.h io_uring: unexport io_req_cqe_overflow() 2024-04-15 08:10:26 -06:00
kbuf.c io_uring/kbuf: remove dead define 2024-04-15 08:10:26 -06:00
kbuf.h io_uring: return void from io_put_kbuf_comp() 2024-04-15 08:10:26 -06:00
Makefile io_uring: move mapping/allocation helpers to a separate file 2024-04-15 08:10:26 -06:00
memmap.c io_uring: move mapping/allocation helpers to a separate file 2024-04-15 08:10:26 -06:00
memmap.h io_uring: move mapping/allocation helpers to a separate file 2024-04-15 08:10:26 -06:00
msg_ring.c io_uring: use io_file_from_index in io_msg_grab_file 2023-06-20 09:36:22 -06:00
msg_ring.h io_uring: get rid of double locking 2022-12-07 06:47:13 -07:00
napi.c io_uring/napi: enable even with a timeout of 0 2024-02-15 15:37:28 -07:00
napi.h io_uring: add register/unregister napi function 2024-02-09 11:54:32 -07:00
net.c io_uring/net: set MSG_ZEROCOPY for sendzc in advance 2024-04-15 08:10:26 -06:00
net.h io_uring/alloc_cache: switch to array based caching 2024-04-15 08:10:25 -06:00
nop.c
nop.h
notif.c io_uring/notif: remove ctx var from io_notif_tw_complete 2024-04-15 08:10:49 -06:00
notif.h io_uring/notif: shrink account_pages to u32 2024-04-15 08:10:49 -06:00
opdef.c io_uring: drop ->prep_async() 2024-04-15 08:10:25 -06:00
opdef.h io_uring: drop ->prep_async() 2024-04-15 08:10:25 -06:00
openclose.c io_uring: enable audit and restrict cred override for IORING_OP_FIXED_FD_INSTALL 2024-01-23 15:25:14 -07:00
openclose.h io_uring/openclose: add support for IORING_OP_FIXED_FD_INSTALL 2023-12-12 07:42:57 -07:00
poll.c io_uring/alloc_cache: switch to array based caching 2024-04-15 08:10:25 -06:00
poll.h io_uring/poll: shrink alloc cache size to 32 2024-04-15 08:10:25 -06:00
refs.h io_uring: kill dead code in io_req_complete_post 2024-04-15 08:10:26 -06:00
register.c io_uring: fix warnings on shadow variables 2024-04-15 08:10:26 -06:00
register.h io_uring/register: move io_uring_register(2) related code to register.c 2023-12-19 08:54:20 -07:00
rsrc.c io_uring: move mapping/allocation helpers to a separate file 2024-04-15 08:10:26 -06:00
rsrc.h io_uring: remove io_req_put_rsrc_locked() 2024-04-15 08:10:26 -06:00
rw.c io_uring/alloc_cache: switch to array based caching 2024-04-15 08:10:25 -06:00
rw.h io_uring/alloc_cache: switch to array based caching 2024-04-15 08:10:25 -06:00
slist.h io_uring: silence variable ‘prev’ set but not used warning 2023-03-09 10:10:58 -07:00
splice.c splice: return type ssize_t from all helpers 2023-12-12 16:19:59 +01:00
splice.h
sqpoll.c io_uring/sqpoll: work around a potential audit memory leak 2024-04-15 13:06:19 -06:00
sqpoll.h io_uring/sqpoll: statistics of the true utilization of sq threads 2024-03-01 06:28:19 -07:00
statx.c io_uring: for requests that require async, force it 2023-01-29 15:18:26 -07:00
statx.h
sync.c io_uring: for requests that require async, force it 2023-01-29 15:18:26 -07:00
sync.h
tctx.c io_uring: Add io_uring_setup flag to pre-register ring fd and never install it 2023-05-16 08:06:00 -06:00
tctx.h io_uring: simplify __io_uring_add_tctx_node 2022-10-07 12:25:30 -06:00
timeout.c io_uring/timeout: remove duplicate initialization of the io_timeout list. 2024-04-15 08:10:27 -06:00
timeout.h io_uring: remove unused return from io_disarm_next 2022-09-21 13:15:01 -06:00
truncate.c io_uring: add support for ftruncate 2024-02-09 09:04:39 -07:00
truncate.h io_uring: add support for ftruncate 2024-02-09 09:04:39 -07:00
uring_cmd.c io_uring: separate header for exported net bits 2024-04-15 08:10:26 -06:00
uring_cmd.h io_uring/alloc_cache: switch to array based caching 2024-04-15 08:10:25 -06:00
waitid.c io_uring: remove struct io_tw_state::locked 2024-04-15 08:10:24 -06:00
waitid.h io_uring: add IORING_OP_WAITID support 2023-09-21 12:04:45 -06:00
xattr.c io_uring: use file_mnt_idmap helper 2024-02-06 19:55:14 -07:00
xattr.h