Merge tag 'v6.6.68' into for/openbmc/dev-6.6

This is the 6.6.68 stable release

io_uring/rw: avoid punting to io-wq directly

Commit 6e6b8c62120a22acd8cb759304e4cd2e3215d488 upstream.

kiocb_done() should care to specifically redirecting requests to io-wq.
Remove the hopping to

io_uring/rw: avoid punting to io-wq directly

Commit 6e6b8c62120a22acd8cb759304e4cd2e3215d488 upstream.

kiocb_done() should care to specifically redirecting requests to io-wq.
Remove the hopping to tw to then queue an io-wq, return -EAGAIN and let
the core code io_uring handle offloading.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/413564e550fe23744a970e1783dfa566291b0e6f.1710799188.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
(cherry picked from commit 6e6b8c62120a22acd8cb759304e4cd2e3215d488)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Merge tag 'v6.6.58' into for/openbmc/dev-6.6

This is the 6.6.58 stable release

io_uring/sqpoll: close race on waiting for sqring entries

commit 28aabffae6be54284869a91cd8bccd3720041129 upstream.

When an application uses SQPOLL, it must wait for the SQPOLL thread to
consume SQ

io_uring/sqpoll: close race on waiting for sqring entries

commit 28aabffae6be54284869a91cd8bccd3720041129 upstream.

When an application uses SQPOLL, it must wait for the SQPOLL thread to
consume SQE entries, if it fails to get an sqe when calling
io_uring_get_sqe(). It can do so by calling io_uring_enter(2) with the
flag value of IORING_ENTER_SQ_WAIT. In liburing, this is generally done
with io_uring_sqring_wait(). There's a natural expectation that once
this call returns, a new SQE entry can be retrieved, filled out, and
submitted. However, the kernel uses the cached sq head to determine if
the SQRING is full or not. If the SQPOLL thread is currently in the
process of submitting SQE entries, it may have updated the cached sq
head, but not yet committed it to the SQ ring. Hence the kernel may find
that there are SQE entries ready to be consumed, and return successfully
to the application. If the SQPOLL thread hasn't yet committed the SQ
ring entries by the time the application returns to userspace and
attempts to get a new SQE, it will fail getting a new SQE.

Fix this by having io_sqring_full() always use the user visible SQ ring
head entry, rather than the internally cached one.

Cc: stable@vger.kernel.org # 5.10+
Link: https://github.com/axboe/liburing/discussions/1267
Reported-by: Benedek Thaler <thaler@thaler.hu>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Merge tag 'v6.6.33' into dev-6.6

This is the 6.6.33 stable release

io_uring: use the right type for work_llist empty check

[ Upstream commit 22537c9f79417fed70b352d54d01d2586fee9521 ]

io_task_work_pending() uses wq_list_empty() on ctx->work_llist, but it's
not an

io_uring: use the right type for work_llist empty check

[ Upstream commit 22537c9f79417fed70b352d54d01d2586fee9521 ]

io_task_work_pending() uses wq_list_empty() on ctx->work_llist, but it's
not an io_wq_work_list, it's a struct llist_head. They both have
->first as head-of-list, and it turns out the checks are identical. But
be proper and use the right helper.

Fixes: dac6a0eae793 ("io_uring: ensure iopoll runs local task work as well")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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Merge tag 'v6.6.23' into dev-6.6

Linux 6.6.23

io_uring/unix: drop usage of io_uring socket

Commit a4104821ad651d8a0b374f0b2474c345bbb42f82 upstream.

Since we no longer allow sending io_uring fds over SCM_RIGHTS, move to
using io_is_uring_fops(

io_uring/unix: drop usage of io_uring socket

Commit a4104821ad651d8a0b374f0b2474c345bbb42f82 upstream.

Since we no longer allow sending io_uring fds over SCM_RIGHTS, move to
using io_is_uring_fops() to detect whether this is a io_uring fd or not.
With that done, kill off io_uring_get_socket() as nobody calls it
anymore.

This is in preparation to yanking out the rest of the core related to
unix gc with io_uring.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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Merge tag 'v6.6.17' into dev-6.6

This is the 6.6.17 stable release

io_uring/poll: add requeue return code from poll multishot handling

Commit 704ea888d646cb9d715662944cf389c823252ee0 upstream.

Since our poll handling is edge triggered, multishot handlers retry
int

io_uring/poll: add requeue return code from poll multishot handling

Commit 704ea888d646cb9d715662944cf389c823252ee0 upstream.

Since our poll handling is edge triggered, multishot handlers retry
internally until they know that no more data is available. In
preparation for limiting these retries, add an internal return code,
IOU_REQUEUE, which can be used to inform the poll backend about the
handler wanting to retry, but that this should happen through a normal
task_work requeue rather than keep hammering on the issue side for this
one request.

No functional changes in this patch, nobody is using this return code
just yet.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Merge tag 'v6.6.6' into dev-6.6

This is the 6.6.6 stable release

Signed-off-by: Joel Stanley <joel@jms.id.au>

io_uring: enable io_mem_alloc/free to be used in other parts

commit edecf1689768452ba1a64b7aaf3a47a817da651a upstream.

In preparation for using these helpers, make them non-static and add
them to o

io_uring: enable io_mem_alloc/free to be used in other parts

commit edecf1689768452ba1a64b7aaf3a47a817da651a upstream.

In preparation for using these helpers, make them non-static and add
them to our internal header.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Merge tag 'io_uring-6.6-2023-10-06' of git://git.kernel.dk/linux

Pull io_uring fixes from Jens Axboe:

- syzbot report on a crash on 32-bit arm with highmem, and went digging
to check for potent

Merge tag 'io_uring-6.6-2023-10-06' of git://git.kernel.dk/linux

Pull io_uring fixes from Jens Axboe:

- syzbot report on a crash on 32-bit arm with highmem, and went digging
to check for potentially similar issues and found one more (me)

- Fix a syzbot report with PROVE_LOCKING=y and setting up the ring in a
disabled state (me)

- Fix for race with CPU hotplut and io-wq init (Jeff)

* tag 'io_uring-6.6-2023-10-06' of git://git.kernel.dk/linux:
io-wq: fully initialize wqe before calling cpuhp_state_add_instance_nocalls()
io_uring: don't allow IORING_SETUP_NO_MMAP rings on highmem pages
io_uring: ensure io_lockdep_assert_cq_locked() handles disabled rings
io_uring/kbuf: don't allow registered buffer rings on highmem pages

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io_uring: ensure io_lockdep_assert_cq_locked() handles disabled rings

io_lockdep_assert_cq_locked() checks that locking is correctly done when
a CQE is posted. If the ring is setup in a disabled sta

io_uring: ensure io_lockdep_assert_cq_locked() handles disabled rings

io_lockdep_assert_cq_locked() checks that locking is correctly done when
a CQE is posted. If the ring is setup in a disabled state with
IORING_SETUP_R_DISABLED, then ctx->submitter_task isn't assigned until
the ring is later enabled. We generally don't post CQEs in this state,
as no SQEs can be submitted. However it is possible to generate a CQE
if tagged resources are being updated. If this happens and PROVE_LOCKING
is enabled, then the locking check helper will dereference
ctx->submitter_task, which hasn't been set yet.

Fixup io_lockdep_assert_cq_locked() to handle this case correctly. While
at it, convert it to a static inline as well, so that generated line
offsets will actually reflect which condition failed, rather than just
the line offset for io_lockdep_assert_cq_locked() itself.

Reported-and-tested-by: syzbot+efc45d4e7ba6ab4ef1eb@syzkaller.appspotmail.com
Fixes: f26cc9593581 ("io_uring: lockdep annotate CQ locking")
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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Merge drm/drm-fixes into drm-misc-fixes

Forwarding to v6.6-rc1.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge branch 'next' into for-linus

Prepare input updates for 6.6 merge window.

Merge tag 'for-6.6/io_uring-2023-08-28' of git://git.kernel.dk/linux

Pull io_uring updates from Jens Axboe:
"Fairly quiet round in terms of features, mostly just improvements all
over the map for

Merge tag 'for-6.6/io_uring-2023-08-28' of git://git.kernel.dk/linux

Pull io_uring updates from Jens Axboe:
"Fairly quiet round in terms of features, mostly just improvements all
over the map for existing code. In detail:

- Initial support for socket operations through io_uring. Latter half
of this will likely land with the 6.7 kernel, then allowing things
like get/setsockopt (Breno)

- Cleanup of the cancel code, and then adding support for canceling
requests with the opcode as the key (me)

- Improvements for the io-wq locking (me)

- Fix affinity setting for SQPOLL based io-wq (me)

- Remove the io_uring userspace code. These were added initially as
copies from liburing, but all of them have since bitrotted and are
way out of date at this point. Rather than attempt to keep them in
sync, just get rid of them. People will have liburing available
anyway for these examples. (Pavel)

- Series improving the CQ/SQ ring caching (Pavel)

- Misc fixes and cleanups (Pavel, Yue, me)"

* tag 'for-6.6/io_uring-2023-08-28' of git://git.kernel.dk/linux: (47 commits)
io_uring: move iopoll ctx fields around
io_uring: move multishot cqe cache in ctx
io_uring: separate task_work/waiting cache line
io_uring: banish non-hot data to end of io_ring_ctx
io_uring: move non aligned field to the end
io_uring: add option to remove SQ indirection
io_uring: compact SQ/CQ heads/tails
io_uring: force inline io_fill_cqe_req
io_uring: merge iopoll and normal completion paths
io_uring: reorder cqring_flush and wakeups
io_uring: optimise extra io_get_cqe null check
io_uring: refactor __io_get_cqe()
io_uring: simplify big_cqe handling
io_uring: cqe init hardening
io_uring: improve cqe !tracing hot path
io_uring/rsrc: Annotate struct io_mapped_ubuf with __counted_by
io_uring/sqpoll: fix io-wq affinity when IORING_SETUP_SQPOLL is used
io_uring: simplify io_run_task_work_sig return
io_uring/rsrc: keep one global dummy_ubuf
io_uring: never overflow io_aux_cqe
...

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io_uring: force inline io_fill_cqe_req

There are only 2 callers of io_fill_cqe_req left, and one of them is
extremely hot. Force inline the function.

Signed-off-by: Pavel Begunkov <asml.silence@gma

io_uring: force inline io_fill_cqe_req

There are only 2 callers of io_fill_cqe_req left, and one of them is
extremely hot. Force inline the function.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/ffce4fc5e3521966def848a4d930586dfe33ae11.1692916914.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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io_uring: merge iopoll and normal completion paths

io_do_iopoll() and io_submit_flush_completions() are pretty similar,
both filling CQEs and then free a list of requests. Don't duplicate it
and mak

io_uring: merge iopoll and normal completion paths

io_do_iopoll() and io_submit_flush_completions() are pretty similar,
both filling CQEs and then free a list of requests. Don't duplicate it
and make iopoll use __io_submit_flush_completions(), which also helps
with inlining and other optimisations.

For that, we need to first find all completed iopoll requests and splice
them from the iopoll list and then pass it down. This adds one extra
list traversal, which should be fine as requests will stay hot in cache.

CQ locking is already conditional, introduce ->lockless_cq and skip
locking for IOPOLL as it's protected by ->uring_lock.

We also add a wakeup optimisation for IOPOLL to __io_cq_unlock_post(),
so it works just like io_cqring_ev_posted_iopoll().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/3840473f5e8a960de35b77292026691880f6bdbc.1692916914.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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io_uring: optimise extra io_get_cqe null check

If the cached cqe check passes in io_get_cqe*() it already means that
the cqe we return is valid and non-zero, however the compiler is unable
to optimi

io_uring: optimise extra io_get_cqe null check

If the cached cqe check passes in io_get_cqe*() it already means that
the cqe we return is valid and non-zero, however the compiler is unable
to optimise null checks like in io_fill_cqe_req().

Do a bit of trickery, return success/fail boolean from io_get_cqe*()
and store cqe in the cqe parameter. That makes it do the right thing,
erasing the check together with the introduced indirection.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/322ea4d3377d3d4efd8ae90ab8ed28a99f518210.1692916914.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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io_uring: refactor __io_get_cqe()

Make __io_get_cqe simpler by not grabbing the cqe from refilled cached,
but letting io_get_cqe() do it for us. That's cleaner and removes some
duplication.

Signed-

io_uring: refactor __io_get_cqe()

Make __io_get_cqe simpler by not grabbing the cqe from refilled cached,
but letting io_get_cqe() do it for us. That's cleaner and removes some
duplication.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/74dc8fdf2657e438b2e05e1d478a3596924604e9.1692916914.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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io_uring: simplify big_cqe handling

Don't keep big_cqe bits of req in a union with hash_node, find a
separate space for it. It's bit safer, but also if we keep it always
initialised, we can get rid

io_uring: simplify big_cqe handling

Don't keep big_cqe bits of req in a union with hash_node, find a
separate space for it. It's bit safer, but also if we keep it always
initialised, we can get rid of ugly REQ_F_CQE32_INIT handling.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/447aa1b2968978c99e655ba88db536e903df0fe9.1692916914.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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io_uring: improve cqe !tracing hot path

While looking at io_fill_cqe_req()'s asm I stumbled on our trace points
turning into the chunk below:

trace_io_uring_complete(req->ctx, req, req->cqe.user_da

io_uring: improve cqe !tracing hot path

While looking at io_fill_cqe_req()'s asm I stumbled on our trace points
turning into the chunk below:

trace_io_uring_complete(req->ctx, req, req->cqe.user_data,
req->cqe.res, req->cqe.flags,
req->extra1, req->extra2);

io_uring/io_uring.c:898: trace_io_uring_complete(req->ctx, req, req->cqe.user_data,
movq 232(%rbx), %rdi # req_44(D)->big_cqe.extra2, _5
movq 224(%rbx), %rdx # req_44(D)->big_cqe.extra1, _6
movl 84(%rbx), %r9d # req_44(D)->cqe.D.81184.flags, _7
movl 80(%rbx), %r8d # req_44(D)->cqe.res, _8
movq 72(%rbx), %rcx # req_44(D)->cqe.user_data, _9
movq 88(%rbx), %rsi # req_44(D)->ctx, _10
./arch/x86/include/asm/jump_label.h:27: asm_volatile_goto("1:"
1:jmp .L1772 # objtool NOPs this #
...

It does a jump_label for actual tracing, but those 6 moves will stay
there in the hottest io_uring path. As an optimisation, add a
trace_io_uring_complete_enabled() check, which is also uses jump_labels,
it tricks the compiler into behaving. It removes the junk without
changing anything else int the hot path.

Note: apparently, it's not only me noticing it, and people are also
working it around. We should remove the check when it's solved
generically or rework tracing.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/555d8312644b3776f4be7e23f9b92943875c4bc7.1692916914.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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io_uring: never overflow io_aux_cqe

Now all callers of io_aux_cqe() set allow_overflow to false, remove the
parameter and not allow overflowing auxilary multishot cqes.

When CQ is full the function

io_uring: never overflow io_aux_cqe

Now all callers of io_aux_cqe() set allow_overflow to false, remove the
parameter and not allow overflowing auxilary multishot cqes.

When CQ is full the function callers and all multishot requests in
general are expected to complete the request. That prevents indefinite
in-background grows of the overflow list and let's the userspace to
handle the backlog at its own pace.

Resubmitting a request should also be faster than accounting a bunch of
overflows, so it should be better for perf when it happens, but a well
behaving userspace should be trying to avoid overflows in any case.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/bb20d14d708ea174721e58bb53786b0521e4dd6d.1691757663.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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io_uring: remove return from io_req_cqe_overflow()

Nobody checks io_req_cqe_overflow()'s return, make it return void.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kerne

io_uring: remove return from io_req_cqe_overflow()

Nobody checks io_req_cqe_overflow()'s return, make it return void.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/8f2029ad0c22f73451664172d834372608ee0a77.1691757663.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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