Commit Graph

784 Commits

Author SHA1 Message Date
Jens Axboe 13b01aedb5 io_uring/net: fix multishot accept overflow handling
commit a37ee9e117ef73bbc2f5c0b31911afd52d229861 upstream.

If we hit CQ ring overflow when attempting to post a multishot accept
completion, we don't properly save the result or return code. This
results in losing the accepted fd value.

Instead, we return the result from the poll operation that triggered
the accept retry. This is generally POLLIN|POLLPRI|POLLRDNORM|POLLRDBAND
which is 0xc3, or 195, which looks like a valid file descriptor, but it
really has no connection to that.

Handle this like we do for other multishot completions - assign the
result, and return IOU_STOP_MULTISHOT to cancel any further completions
from this request when overflow is hit. This preserves the result, as we
should, and tells the application that the request needs to be re-armed.

Cc: stable@vger.kernel.org
Fixes: 515e269612 ("io_uring: revert "io_uring fix multishot accept ordering"")
Link: https://github.com/axboe/liburing/issues/1062
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:25:10 +01:00
Jens Axboe 22ccf61c33 io_uring/net: limit inline multishot retries
Commit 76b367a2d83163cf19173d5cb0b562acbabc8eac upstream.

If we have multiple clients and some/all are flooding the receives to
such an extent that we can retry a LOT handling multishot receives, then
we can be starving some clients and hence serving traffic in an
imbalanced fashion.

Limit multishot retry attempts to some arbitrary value, whose only
purpose serves to ensure that we don't keep serving a single connection
for way too long. We default to 32 retries, which should be more than
enough to provide fairness, yet not so small that we'll spend too much
time requeuing rather than handling traffic.

Cc: stable@vger.kernel.org
Depends-on: 704ea888d646 ("io_uring/poll: add requeue return code from poll multishot handling")
Depends-on: 1e5d765a82f ("io_uring/net: un-indent mshot retry path in io_recv_finish()")
Depends-on: e84b01a880f6 ("io_uring/poll: move poll execution helpers higher up")
Fixes: b3fdea6ecb ("io_uring: multishot recv")
Fixes: 9bb66906f2 ("io_uring: support multishot in recvmsg")
Link: https://github.com/axboe/liburing/issues/1043
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-16 19:10:56 +01:00
Jens Axboe 7cbd3aa59d 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>
2024-02-16 19:10:56 +01:00
Jens Axboe eac52bfe23 io_uring/net: un-indent mshot retry path in io_recv_finish()
Commit 91e5d765a82fb2c9d0b7ad930d8953208081ddf1 upstream.

In preparation for putting some retry logic in there, have the done
path just skip straight to the end rather than have too much nesting
in here.

No functional changes in this patch.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-16 19:10:56 +01:00
Jens Axboe 0848bf7e53 io_uring/poll: move poll execution helpers higher up
Commit e84b01a880f635e3084a361afba41f95ff500d12 upstream.

In preparation for calling __io_poll_execute() higher up, move the
functions to avoid forward declarations.

No functional changes in this patch.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-16 19:10:56 +01:00
Jens Axboe 0ceb7a9230 io_uring/net: fix sr->len for IORING_OP_RECV with MSG_WAITALL and buffers
commit 72bd80252feeb3bef8724230ee15d9f7ab541c6e upstream.

If we use IORING_OP_RECV with provided buffers and pass in '0' as the
length of the request, the length is retrieved from the selected buffer.
If MSG_WAITALL is also set and we get a short receive, then we may hit
the retry path which decrements sr->len and increments the buffer for
a retry. However, the length is still zero at this point, which means
that sr->len now becomes huge and import_ubuf() will cap it to
MAX_RW_COUNT and subsequently return -EFAULT for the range as a whole.

Fix this by always assigning sr->len once the buffer has been selected.

Cc: stable@vger.kernel.org
Fixes: 7ba89d2af1 ("io_uring: ensure recv and recvmsg handle MSG_WAITALL correctly")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-16 19:10:56 +01:00
Pavel Begunkov 8836df0212 io_uring: adjust defer tw counting
[ Upstream commit dc12d1799ce710fd90abbe0ced71e7e1ae0894fc ]

The UINT_MAX work item counting bias in io_req_local_work_add() in case
of !IOU_F_TWQ_LAZY_WAKE works in a sense that we will not miss a wake up,
however it's still eerie. In particular, if we add a lazy work item
after a non-lazy one, we'll increment it and get nr_tw==0, and
subsequent adds may try to unnecessarily wake up the task, which is
though not so likely to happen in real workloads.

Half the bias, it's still large enough to be larger than any valid
->cq_wait_nr, which is limited by IORING_MAX_CQ_ENTRIES, but further
have a good enough of space before it overflows.

Fixes: 8751d15426 ("io_uring: reduce scheduling due to tw")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/108b971e958deaf7048342930c341ba90f75d806.1705438669.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:36:00 -08:00
Jens Axboe 0241f4c2ca io_uring: ensure local task_work is run on wait timeout
commit 6ff1407e24e6fdfa4a16ba9ba551e3d253a26391 upstream.

A previous commit added an earlier break condition here, which is fine if
we're using non-local task_work as it'll be run on return to userspace.
However, if DEFER_TASKRUN is used, then we could be leaving local
task_work that is ready to process in the ctx list until next time that
we enter the kernel to wait for events.

Move the break condition to _after_ we have run task_work.

Cc: stable@vger.kernel.org
Fixes: 846072f16e ("io_uring: mimimise io_cqring_wait_schedule")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-25 15:35:45 -08:00
Jens Axboe c239b77ea4 io_uring/rw: ensure io->bytes_done is always initialized
commit 0a535eddbe0dc1de4386046ab849f08aeb2f8faf upstream.

If IOSQE_ASYNC is set and we fail importing an iovec for a readv or
writev request, then we leave ->bytes_done uninitialized and hence the
eventual failure CQE posted can potentially have a random res value
rather than the expected -EINVAL.

Setup ->bytes_done before potentially failing, so we have a consistent
value if we fail the request early.

Cc: stable@vger.kernel.org
Reported-by: xingwei lee <xrivendell7@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-25 15:35:45 -08:00
Pavel Begunkov 2c487fbf22 io_uring: don't check iopoll if request completes
commit 9b43ef3d52532a0175ed6654618f7db61d390d2e upstream.

IOPOLL request should never return IOU_OK, so the following iopoll
queueing check in io_issue_sqe() after getting IOU_OK doesn't make any
sense as would never turn true. Let's optimise on that and return a bit
earlier. It's also much more resilient to potential bugs from
mischieving iopoll implementations.

Cc:  <stable@vger.kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/2f8690e2fa5213a2ff292fac29a7143c036cdd60.1701390926.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-25 15:35:45 -08:00
Jens Axboe 0c7df8c241 io_uring: use fget/fput consistently
[ Upstream commit 73363c262d6a7d26063da96610f61baf69a70f7c ]

Normally within a syscall it's fine to use fdget/fdput for grabbing a
file from the file table, and it's fine within io_uring as well. We do
that via io_uring_enter(2), io_uring_register(2), and then also for
cancel which is invoked from the latter. io_uring cannot close its own
file descriptors as that is explicitly rejected, and for the cancel
side of things, the file itself is just used as a lookup cookie.

However, it is more prudent to ensure that full references are always
grabbed. For anything threaded, either explicitly in the application
itself or through use of the io-wq worker threads, this is what happens
anyway. Generalize it and use fget/fput throughout.

Also see the below link for more details.

Link: https://lore.kernel.org/io-uring/CAG48ez1htVSO3TqmrF8QcX2WFuYTRM-VZ_N10i-VZgbtg=NNqw@mail.gmail.com/
Suggested-by: Jann Horn <jannh@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-20 11:51:38 +01:00
Al Viro 9566ef570c io_uring/cmd: fix breakage in SOCKET_URING_OP_SIOC* implementation
commit 1ba0e9d69b2000e95267c888cbfa91d823388d47 upstream.

	In 8e9fad0e70 "io_uring: Add io_uring command support for sockets"
you've got an include of asm-generic/ioctls.h done in io_uring/uring_cmd.c.
That had been done for the sake of this chunk -
+               ret = prot->ioctl(sk, SIOCINQ, &arg);
+               if (ret)
+                       return ret;
+               return arg;
+       case SOCKET_URING_OP_SIOCOUTQ:
+               ret = prot->ioctl(sk, SIOCOUTQ, &arg);

SIOC{IN,OUT}Q are defined to symbols (FIONREAD and TIOCOUTQ) that come from
ioctls.h, all right, but the values vary by the architecture.

FIONREAD is
	0x467F on mips
	0x4004667F on alpha, powerpc and sparc
	0x8004667F on sh and xtensa
	0x541B everywhere else
TIOCOUTQ is
	0x7472 on mips
	0x40047473 on alpha, powerpc and sparc
	0x80047473 on sh and xtensa
	0x5411 everywhere else

->ioctl() expects the same values it would've gotten from userland; all
places where we compare with SIOC{IN,OUT}Q are using asm/ioctls.h, so
they pick the correct values.  io_uring_cmd_sock(), OTOH, ends up
passing the default ones.

Fixes: 8e9fad0e70 ("io_uring: Add io_uring command support for sockets")
Cc:  <stable@vger.kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20231214213408.GT1674809@ZenIV
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-20 17:01:52 +01:00
Pavel Begunkov 30df2901c4 io_uring: fix mutex_unlock with unreferenced ctx
commit f7b32e785042d2357c5abc23ca6db1b92c91a070 upstream.

Callers of mutex_unlock() have to make sure that the mutex stays alive
for the whole duration of the function call. For io_uring that means
that the following pattern is not valid unless we ensure that the
context outlives the mutex_unlock() call.

mutex_lock(&ctx->uring_lock);
req_put(req); // typically via io_req_task_submit()
mutex_unlock(&ctx->uring_lock);

Most contexts are fine: io-wq pins requests, syscalls hold the file,
task works are taking ctx references and so on. However, the task work
fallback path doesn't follow the rule.

Cc:  <stable@vger.kernel.org>
Fixes: 04fc6c802d ("io_uring: save ctx put/get for task_work submit")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/io-uring/CAG48ez3xSoYb+45f1RLtktROJrpiDQ1otNvdR+YLQf7m+Krj5Q@mail.gmail.com/
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-13 18:45:20 +01:00
Pavel Begunkov 5a33d385eb io_uring/af_unix: disable sending io_uring over sockets
commit 705318a99a138c29a512a72c3e0043b3cd7f55f4 upstream.

File reference cycles have caused lots of problems for io_uring
in the past, and it still doesn't work exactly right and races with
unix_stream_read_generic(). The safest fix would be to completely
disallow sending io_uring files via sockets via SCM_RIGHT, so there
are no possible cycles invloving registered files and thus rendering
SCM accounting on the io_uring side unnecessary.

Cc:  <stable@vger.kernel.org>
Fixes: 0091bfc817 ("io_uring/af_unix: defer registered files gc to io_uring release")
Reported-and-suggested-by: Jann Horn <jannh@google.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c716c88321939156909cfa1bd8b0faaf1c804103.1701868795.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-13 18:45:20 +01:00
Jens Axboe 7e6621b99d io_uring/kbuf: check for buffer list readiness after NULL check
[ Upstream commit 9865346b7e8374b57f1c3ccacdc77846c6352ff4 ]

Move the buffer list 'is_ready' check below the validity check for
the buffer list for a given group.

Fixes: 5cf4f52e6d8a ("io_uring: free io_buffer_list entries via RCU")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13 18:45:17 +01:00
Dan Carpenter b2173a8b64 io_uring/kbuf: Fix an NULL vs IS_ERR() bug in io_alloc_pbuf_ring()
[ Upstream commit e53f7b54b1fdecae897f25002ff0cff04faab228 ]

The io_mem_alloc() function returns error pointers, not NULL.  Update
the check accordingly.

Fixes: b10b73c102a2 ("io_uring/kbuf: recycle freed mapped buffer ring entries")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/5ed268d3-a997-4f64-bd71-47faa92101ab@moroto.mountain
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13 18:45:17 +01:00
Jens Axboe 9e1152a6c2 io_uring/kbuf: recycle freed mapped buffer ring entries
commit b10b73c102a2eab91e1cd62a03d6446f1dfecc64 upstream.

Right now we stash any potentially mmap'ed provided ring buffer range
for freeing at release time, regardless of when they get unregistered.
Since we're keeping track of these ranges anyway, keep track of their
registration state as well, and use that to recycle ranges when
appropriate rather than always allocate new ones.

The lookup is a basic scan of entries, checking for the best matching
free entry.

Fixes: c392cbecd8ec ("io_uring/kbuf: defer release of mapped buffer rings")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-08 08:52:21 +01:00
Jens Axboe 7138ebbe65 io_uring/kbuf: defer release of mapped buffer rings
commit c392cbecd8eca4c53f2bf508731257d9d0a21c2d upstream.

If a provided buffer ring is setup with IOU_PBUF_RING_MMAP, then the
kernel allocates the memory for it and the application is expected to
mmap(2) this memory. However, io_uring uses remap_pfn_range() for this
operation, so we cannot rely on normal munmap/release on freeing them
for us.

Stash an io_buf_free entry away for each of these, if any, and provide
a helper to free them post ->release().

Cc: stable@vger.kernel.org
Fixes: c56e022c0a ("io_uring: add support for user mapped provided buffer ring")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-08 08:52:20 +01:00
Jens Axboe 4ca5f54af7 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>
2023-12-08 08:52:20 +01:00
Jens Axboe b797b7f83e io_uring: don't guard IORING_OFF_PBUF_RING with SETUP_NO_MMAP
commit 6f007b1406637d3d73d42e41d7e8d9b245185e69 upstream.

This flag only applies to the SQ and CQ rings, it's perfectly valid
to use a mmap approach for the provided ring buffers. Move the
check into where it belongs.

Cc: stable@vger.kernel.org
Fixes: 03d89a2de2 ("io_uring: support for user allocated memory for rings/sqes")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-08 08:52:19 +01:00
Jens Axboe 09f7520048 io_uring: free io_buffer_list entries via RCU
commit 5cf4f52e6d8aa2d3b7728f568abbf9d42a3af252 upstream.

mmap_lock nests under uring_lock out of necessity, as we may be doing
user copies with uring_lock held. However, for mmap of provided buffer
rings, we attempt to grab uring_lock with mmap_lock already held from
do_mmap(). This makes lockdep, rightfully, complain:

WARNING: possible circular locking dependency detected
6.7.0-rc1-00009-gff3337ebaf94-dirty #4438 Not tainted
------------------------------------------------------
buf-ring.t/442 is trying to acquire lock:
ffff00020e1480a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_validate_mmap_request.isra.0+0x4c/0x140

but task is already holding lock:
ffff0000dc226190 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x124/0x264

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&mm->mmap_lock){++++}-{3:3}:
       __might_fault+0x90/0xbc
       io_register_pbuf_ring+0x94/0x488
       __arm64_sys_io_uring_register+0x8dc/0x1318
       invoke_syscall+0x5c/0x17c
       el0_svc_common.constprop.0+0x108/0x130
       do_el0_svc+0x2c/0x38
       el0_svc+0x4c/0x94
       el0t_64_sync_handler+0x118/0x124
       el0t_64_sync+0x168/0x16c

-> #0 (&ctx->uring_lock){+.+.}-{3:3}:
       __lock_acquire+0x19a0/0x2d14
       lock_acquire+0x2e0/0x44c
       __mutex_lock+0x118/0x564
       mutex_lock_nested+0x20/0x28
       io_uring_validate_mmap_request.isra.0+0x4c/0x140
       io_uring_mmu_get_unmapped_area+0x3c/0x98
       get_unmapped_area+0xa4/0x158
       do_mmap+0xec/0x5b4
       vm_mmap_pgoff+0x158/0x264
       ksys_mmap_pgoff+0x1d4/0x254
       __arm64_sys_mmap+0x80/0x9c
       invoke_syscall+0x5c/0x17c
       el0_svc_common.constprop.0+0x108/0x130
       do_el0_svc+0x2c/0x38
       el0_svc+0x4c/0x94
       el0t_64_sync_handler+0x118/0x124
       el0t_64_sync+0x168/0x16c

From that mmap(2) path, we really just need to ensure that the buffer
list doesn't go away from underneath us. For the lower indexed entries,
they never go away until the ring is freed and we can always sanely
reference those as long as the caller has a file reference. For the
higher indexed ones in our xarray, we just need to ensure that the
buffer list remains valid while we return the address of it.

Free the higher indexed io_buffer_list entries via RCU. With that we can
avoid needing ->uring_lock inside mmap(2), and simply hold the RCU read
lock around the buffer list lookup and address check.

To ensure that the arrayed lookup either returns a valid fully formulated
entry via RCU lookup, add an 'is_ready' flag that we access with store
and release memory ordering. This isn't needed for the xarray lookups,
but doesn't hurt either. Since this isn't a fast path, retain it across
both types. Similarly, for the allocated array inside the ctx, ensure
we use the proper load/acquire as setup could in theory be running in
parallel with mmap.

While in there, add a few lockdep checks for documentation purposes.

Cc: stable@vger.kernel.org
Fixes: c56e022c0a ("io_uring: add support for user mapped provided buffer ring")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-08 08:52:18 +01:00
Jens Axboe 4be625ba36 io_uring: don't allow discontig pages for IORING_SETUP_NO_MMAP
commit 820d070feb668aab5bc9413c285a1dda2a70e076 upstream.

io_sqes_map() is used rather than io_mem_alloc(), if the application
passes in memory for mapping rather than have the kernel allocate it and
then mmap(2) the ranges. This then calls __io_uaddr_map() to perform the
page mapping and pinning, which checks if we end up with the same pages,
if more than one page is mapped. But this check is incorrect and only
checks if the first and last pages are the same, where it really should
be checking if the mapped pages are contigous. This allows mapping a
single normal page, or a huge page range.

Down the line we can add support for remapping pages to be virtually
contigous, which is really all that io_uring cares about.

Cc: stable@vger.kernel.org
Fixes: 03d89a2de2 ("io_uring: support for user allocated memory for rings/sqes")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-08 08:52:18 +01:00
Charles Mirabile ed869aee2a io_uring/fs: consider link->flags when getting path for LINKAT
commit 8479063f1fbee201a8739130e816cc331b675838 upstream.

In order for `AT_EMPTY_PATH` to work as expected, the fact
that the user wants that behavior needs to make it to `getname_flags`
or it will return ENOENT.

Fixes: cf30da90bc ("io_uring: add support for IORING_OP_LINKAT")
Cc:  <stable@vger.kernel.org>
Link: https://github.com/axboe/liburing/issues/995
Signed-off-by: Charles Mirabile <cmirabil@redhat.com>
Link: https://lore.kernel.org/r/20231120105545.1209530-1-cmirabil@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-03 07:33:07 +01:00
Keith Busch 9ab2b08473 io_uring: fix off-by one bvec index
commit d6fef34ee4d102be448146f24caf96d7b4a05401 upstream.

If the offset equals the bv_len of the first registered bvec, then the
request does not include any of that first bvec. Skip it so that drivers
don't have to deal with a zero length bvec, which was observed to break
NVMe's PRP list creation.

Cc: stable@vger.kernel.org
Fixes: bd11b3a391 ("io_uring: don't use iov_iter_advance() for fixed buffers")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20231120221831.2646460-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-03 07:33:07 +01:00
Jens Axboe 5753dbb326 io_uring/fdinfo: remove need for sqpoll lock for thread/pid retrieval
[ Upstream commit a0d45c3f596be53c1bd8822a1984532d14fdcea9 ]

A previous commit added a trylock for getting the SQPOLL thread info via
fdinfo, but this introduced a regression where we often fail to get it if
the thread is busy. For that case, we end up not printing the current CPU
and PID info.

Rather than rely on this lock, just print the pid we already stored in
the io_sq_data struct, and ensure we update the current CPU every time
we've slept or potentially rescheduled. The latter won't potentially be
100% accurate, but that wasn't the case before either as the task can
get migrated at any time unless it has been pinned at creation time.

We retain keeping the io_sq_data dereference inside the ctx->uring_lock,
as it has always been, as destruction of the thread and data happen below
that. We could make this RCU safe, but there's little point in doing that.

With this, we always print the last valid information we had, rather than
have spurious outputs with missing information.

Fixes: 7644b1a1c9 ("io_uring/fdinfo: lock SQ thread while retrieving thread cpu/pid")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 17:19:52 +00:00
Jens Axboe 2bb15fb665 io_uring/net: ensure socket is marked connected on connect retry
commit f8f9ab2d98116e79d220f1d089df7464ad4e026d upstream.

io_uring does non-blocking connection attempts, which can yield some
unexpected results if a connect request is re-attempted by an an
application. This is equivalent to the following sync syscall sequence:

sock = socket(AF_INET, SOCK_STREAM | SOCK_NONBLOCK, IPPROTO_TCP);
connect(sock, &addr, sizeof(addr);

ret == -1 and errno == EINPROGRESS expected here. Now poll for POLLOUT
on sock, and when that returns, we expect the socket to be connected.
But if we follow that procedure with:

connect(sock, &addr, sizeof(addr));

you'd expect ret == -1 and errno == EISCONN here, but you actually get
ret == 0. If we attempt the connection one more time, then we get EISCON
as expected.

io_uring used to do this, but turns out that bluetooth fails with EBADFD
if you attempt to re-connect. Also looks like EISCONN _could_ occur with
this sequence.

Retain the ->in_progress logic, but work-around a potential EISCONN or
EBADFD error and only in those cases look at the sock_error(). This
should work in general and avoid the odd sequence of a repeated connect
request returning success when the socket is already connected.

This is all a side effect of the socket state being in a CONNECTING
state when we get EINPROGRESS, and only a re-connect or other related
operation will turn that into CONNECTED.

Cc: stable@vger.kernel.org
Fixes: 3fb1bd6881 ("io_uring/net: handle -EINPROGRESS correct for IORING_OP_CONNECT")
Link: https://github.com/axboe/liburing/issues/980
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-20 11:59:38 +01:00
Gabriel Krisman Bertazi 464848643e io_uring/kbuf: Allow the full buffer id space for provided buffers
[ Upstream commit f74c746e476b9dad51448b9a9421aae72b60e25f ]

nbufs tracks the number of buffers and not the last bgid. In 16-bit, we
have 2^16 valid buffers, but the check mistakenly rejects the last
bid. Let's fix it to make the interface consistent with the
documentation.

Fixes: ddf0322db7 ("io_uring: add IORING_OP_PROVIDE_BUFFERS")
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://lore.kernel.org/r/20231005000531.30800-3-krisman@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 11:59:11 +01:00
Gabriel Krisman Bertazi de92bc45c0 io_uring/kbuf: Fix check of BID wrapping in provided buffers
[ Upstream commit ab69838e7c75b0edb699c1a8f42752b30333c46f ]

Commit 3851d25c75 ("io_uring: check for rollover of buffer ID when
providing buffers") introduced a check to prevent wrapping the BID
counter when sqe->off is provided, but it's off-by-one too
restrictive, rejecting the last possible BID (65534).

i.e., the following fails with -EINVAL.

     io_uring_prep_provide_buffers(sqe, addr, size, 0xFFFF, 0, 0);

Fixes: 3851d25c75 ("io_uring: check for rollover of buffer ID when providing buffers")
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://lore.kernel.org/r/20231005000531.30800-2-krisman@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 11:59:11 +01:00
Linus Torvalds d1b0949f23 assorted fixes all over the place
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Merge tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull misc filesystem fixes from Al Viro:
 "Assorted fixes all over the place: literally nothing in common, could
  have been three separate pull requests.

  All are simple regression fixes, but not for anything from this cycle"

* tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ceph_wait_on_conflict_unlink(): grab reference before dropping ->d_lock
  io_uring: kiocb_done() should *not* trust ->ki_pos if ->{read,write}_iter() failed
  sparc32: fix a braino in fault handling in csum_and_copy_..._user()
2023-10-27 16:44:58 -10:00
Al Viro 1939316bf9 io_uring: kiocb_done() should *not* trust ->ki_pos if ->{read,write}_iter() failed
->ki_pos value is unreliable in such cases.  For an obvious example,
consider O_DSYNC write - we feed the data to page cache and start IO,
then we make sure it's completed.  Update of ->ki_pos is dealt with
by the first part; failure in the second ends up with negative value
returned _and_ ->ki_pos left advanced as if sync had been successful.
In the same situation write(2) does not advance the file position
at all.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2023-10-27 20:14:11 -04:00
Jens Axboe 838b35bb6a io_uring/rw: disable IOCB_DIO_CALLER_COMP
If an application does O_DIRECT writes with io_uring and the file system
supports IOCB_DIO_CALLER_COMP, then completions of the dio write side is
done from the task_work that will post the completion event for said
write as well.

Whenever a dio write is done against a file, the inode i_dio_count is
elevated. This enables other callers to use inode_dio_wait() to wait for
previous writes to complete. If we defer the full dio completion to
task_work, we are dependent on that task_work being run before the
inode i_dio_count can be decremented.

If the same task that issues io_uring dio writes with
IOCB_DIO_CALLER_COMP performs a synchronous system call that calls
inode_dio_wait(), then we can deadlock as we're blocked sleeping on
the event to become true, but not processing the completions that will
result in the inode i_dio_count being decremented.

Until we can guarantee that this is the case, then disable the deferred
caller completions.

Fixes: 099ada2c87 ("io_uring/rw: add write support for IOCB_DIO_CALLER_COMP")
Reported-by: Andres Freund <andres@anarazel.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-10-25 08:02:29 -06:00
Jens Axboe 7644b1a1c9 io_uring/fdinfo: lock SQ thread while retrieving thread cpu/pid
We could race with SQ thread exit, and if we do, we'll hit a NULL pointer
dereference when the thread is cleared. Grab the SQPOLL data lock before
attempting to get the task cpu and pid for fdinfo, this ensures we have a
stable view of it.

Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=218032
Reviewed-by: Gabriel Krisman Bertazi <krisman@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-10-25 07:44:14 -06:00
Jens Axboe 8b51a3956d io_uring: fix crash with IORING_SETUP_NO_MMAP and invalid SQ ring address
If we specify a valid CQ ring address but an invalid SQ ring address,
we'll correctly spot this and free the allocated pages and clear them
to NULL. However, we don't clear the ring page count, and hence will
attempt to free the pages again. We've already cleared the address of
the page array when freeing them, but we don't check for that. This
causes the following crash:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Oops [#1]
Modules linked in:
CPU: 0 PID: 20 Comm: kworker/u2:1 Not tainted 6.6.0-rc5-dirty #56
Hardware name: ucbbar,riscvemu-bare (DT)
Workqueue: events_unbound io_ring_exit_work
epc : io_pages_free+0x2a/0x58
 ra : io_rings_free+0x3a/0x50
 epc : ffffffff808811a2 ra : ffffffff80881406 sp : ffff8f80000c3cd0
 status: 0000000200000121 badaddr: 0000000000000000 cause: 000000000000000d
 [<ffffffff808811a2>] io_pages_free+0x2a/0x58
 [<ffffffff80881406>] io_rings_free+0x3a/0x50
 [<ffffffff80882176>] io_ring_exit_work+0x37e/0x424
 [<ffffffff80027234>] process_one_work+0x10c/0x1f4
 [<ffffffff8002756e>] worker_thread+0x252/0x31c
 [<ffffffff8002f5e4>] kthread+0xc4/0xe0
 [<ffffffff8000332a>] ret_from_fork+0xa/0x1c

Check for a NULL array in io_pages_free(), but also clear the page counts
when we free them to be on the safer side.

Reported-by: rtm@csail.mit.edu
Fixes: 03d89a2de2 ("io_uring: support for user allocated memory for rings/sqes")
Cc: stable@vger.kernel.org
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-10-18 09:22:14 -06:00
Jeff Moyer 0f8baa3c98 io-wq: fully initialize wqe before calling cpuhp_state_add_instance_nocalls()
I received a bug report with the following signature:

[ 1759.937637] BUG: unable to handle page fault for address: ffffffffffffffe8
[ 1759.944564] #PF: supervisor read access in kernel mode
[ 1759.949732] #PF: error_code(0x0000) - not-present page
[ 1759.954901] PGD 7ab615067 P4D 7ab615067 PUD 7ab617067 PMD 0
[ 1759.960596] Oops: 0000 1 PREEMPT SMP PTI
[ 1759.964804] CPU: 15 PID: 109 Comm: cpuhp/15 Kdump: loaded Tainted: G X ------- — 5.14.0-362.3.1.el9_3.x86_64 #1
[ 1759.976609] Hardware name: HPE ProLiant DL380 Gen10/ProLiant DL380 Gen10, BIOS U30 06/20/2018
[ 1759.985181] RIP: 0010:io_wq_for_each_worker.isra.0+0x24/0xa0
[ 1759.990877] Code: 90 90 90 90 90 90 0f 1f 44 00 00 41 56 41 55 41 54 55 48 8d 6f 78 53 48 8b 47 78 48 39 c5 74 4f 49 89 f5 49 89 d4 48 8d 58 e8 <8b> 13 85 d2 74 32 8d 4a 01 89 d0 f0 0f b1 0b 75 5c 09 ca 78 3d 48
[ 1760.009758] RSP: 0000:ffffb6f403603e20 EFLAGS: 00010286
[ 1760.015013] RAX: 0000000000000000 RBX: ffffffffffffffe8 RCX: 0000000000000000
[ 1760.022188] RDX: ffffb6f403603e50 RSI: ffffffffb11e95b0 RDI: ffff9f73b09e9400
[ 1760.029362] RBP: ffff9f73b09e9478 R08: 000000000000000f R09: 0000000000000000
[ 1760.036536] R10: ffffffffffffff00 R11: ffffb6f403603d80 R12: ffffb6f403603e50
[ 1760.043712] R13: ffffffffb11e95b0 R14: ffffffffb28531e8 R15: ffff9f7a6fbdf548
[ 1760.050887] FS: 0000000000000000(0000) GS:ffff9f7a6fbc0000(0000) knlGS:0000000000000000
[ 1760.059025] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1760.064801] CR2: ffffffffffffffe8 CR3: 00000007ab610002 CR4: 00000000007706e0
[ 1760.071976] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1760.079150] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1760.086325] PKRU: 55555554
[ 1760.089044] Call Trace:
[ 1760.091501] <TASK>
[ 1760.093612] ? show_trace_log_lvl+0x1c4/0x2df
[ 1760.097995] ? show_trace_log_lvl+0x1c4/0x2df
[ 1760.102377] ? __io_wq_cpu_online+0x54/0xb0
[ 1760.106584] ? __die_body.cold+0x8/0xd
[ 1760.110356] ? page_fault_oops+0x134/0x170
[ 1760.114479] ? kernelmode_fixup_or_oops+0x84/0x110
[ 1760.119298] ? exc_page_fault+0xa8/0x150
[ 1760.123247] ? asm_exc_page_fault+0x22/0x30
[ 1760.127458] ? __pfx_io_wq_worker_affinity+0x10/0x10
[ 1760.132453] ? __pfx_io_wq_worker_affinity+0x10/0x10
[ 1760.137446] ? io_wq_for_each_worker.isra.0+0x24/0xa0
[ 1760.142527] __io_wq_cpu_online+0x54/0xb0
[ 1760.146558] cpuhp_invoke_callback+0x109/0x460
[ 1760.151029] ? __pfx_io_wq_cpu_offline+0x10/0x10
[ 1760.155673] ? __pfx_smpboot_thread_fn+0x10/0x10
[ 1760.160320] cpuhp_thread_fun+0x8d/0x140
[ 1760.164266] smpboot_thread_fn+0xd3/0x1a0
[ 1760.168297] kthread+0xdd/0x100
[ 1760.171457] ? __pfx_kthread+0x10/0x10
[ 1760.175225] ret_from_fork+0x29/0x50
[ 1760.178826] </TASK>
[ 1760.181022] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs rfkill sunrpc vfat fat dm_multipath intel_rapl_msr intel_rapl_common isst_if_common ipmi_ssif nfit libnvdimm mgag200 i2c_algo_bit ioatdma drm_shmem_helper drm_kms_helper acpi_ipmi syscopyarea x86_pkg_temp_thermal sysfillrect ipmi_si intel_powerclamp sysimgblt ipmi_devintf coretemp acpi_power_meter ipmi_msghandler rapl pcspkr dca intel_pch_thermal intel_cstate ses lpc_ich intel_uncore enclosure hpilo mei_me mei acpi_tad fuse drm xfs sd_mod sg bnx2x nvme nvme_core crct10dif_pclmul crc32_pclmul nvme_common ghash_clmulni_intel smartpqi tg3 t10_pi mdio uas libcrc32c crc32c_intel scsi_transport_sas usb_storage hpwdt wmi dm_mirror dm_region_hash dm_log dm_mod
[ 1760.248623] CR2: ffffffffffffffe8

A cpu hotplug callback was issued before wq->all_list was initialized.
This results in a null pointer dereference.  The fix is to fully setup
the io_wq before calling cpuhp_state_add_instance_nocalls().

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Link: https://lore.kernel.org/r/x49y1ghnecs.fsf@segfault.boston.devel.redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-10-05 14:11:18 -06:00
Jens Axboe 223ef47431 io_uring: don't allow IORING_SETUP_NO_MMAP rings on highmem pages
On at least arm32, but presumably any arch with highmem, if the
application passes in memory that resides in highmem for the rings,
then we should fail that ring creation. We fail it with -EINVAL, which
is what kernels that don't support IORING_SETUP_NO_MMAP will do as well.

Cc: stable@vger.kernel.org
Fixes: 03d89a2de2 ("io_uring: support for user allocated memory for rings/sqes")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-10-03 09:59:58 -06:00
Jens Axboe 1658633c04 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: f26cc95935 ("io_uring: lockdep annotate CQ locking")
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-10-03 08:12:54 -06:00
Jens Axboe f8024f1f36 io_uring/kbuf: don't allow registered buffer rings on highmem pages
syzbot reports that registering a mapped buffer ring on arm32 can
trigger an OOPS. Registered buffer rings have two modes, one of them
is the application passing in the memory that the buffer ring should
reside in. Once those pages are mapped, we use page_address() to get
a virtual address. This will obviously fail on highmem pages, which
aren't mapped.

Add a check if we have any highmem pages after mapping, and fail the
attempt to register a provided buffer ring if we do. This will return
the same error as kernels that don't support provided buffer rings to
begin with.

Link: https://lore.kernel.org/io-uring/000000000000af635c0606bcb889@google.com/
Fixes: c56e022c0a ("io_uring: add support for user mapped provided buffer ring")
Cc: stable@vger.kernel.org
Reported-by: syzbot+2113e61b8848fa7951d8@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-10-03 08:12:28 -06:00
Jens Axboe a52d4f6575 io_uring/fs: remove sqe->rw_flags checking from LINKAT
This is unionized with the actual link flags, so they can of course be
set and they will be evaluated further down. If not we fail any LINKAT
that has to set option flags.

Fixes: cf30da90bc ("io_uring: add support for IORING_OP_LINKAT")
Cc: stable@vger.kernel.org
Reported-by: Thomas Leonard <talex5@gmail.com>
Link: https://github.com/axboe/liburing/issues/955
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-09-29 03:07:09 -06:00
Pavel Begunkov c21a8027ad io_uring/net: fix iter retargeting for selected buf
When using selected buffer feature, io_uring delays data iter setup
until later. If io_setup_async_msg() is called before that it might see
not correctly setup iterator. Pre-init nr_segs and judge from its state
whether we repointing.

Cc: stable@vger.kernel.org
Reported-by: syzbot+a4c6e5ef999b68b26ed1@syzkaller.appspotmail.com
Fixes: 0455d4ccec ("io_uring: add POLL_FIRST support for send/sendmsg and recv/recvmsg")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0000000000002770be06053c7757@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-09-14 10:12:55 -06:00
Jens Axboe 023464fe33 Revert "io_uring: fix IO hang in io_wq_put_and_exit from do_exit()"
This reverts commit b484a40dc1.

This commit cancels all requests with io-wq, not just the ones from the
originating task. This breaks use cases that have thread pools, or just
multiple tasks issuing requests on the same ring. The liburing
regression test for this also shows that problem:

$ test/thread-exit.t
cqe->res=-125, Expected 512

where an IO thread gets its request canceled rather than complete
successfully.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-09-07 09:41:49 -06:00
Pavel Begunkov 27122c079f io_uring: fix unprotected iopoll overflow
[   71.490669] WARNING: CPU: 3 PID: 17070 at io_uring/io_uring.c:769
io_cqring_event_overflow+0x47b/0x6b0
[   71.498381] Call Trace:
[   71.498590]  <TASK>
[   71.501858]  io_req_cqe_overflow+0x105/0x1e0
[   71.502194]  __io_submit_flush_completions+0x9f9/0x1090
[   71.503537]  io_submit_sqes+0xebd/0x1f00
[   71.503879]  __do_sys_io_uring_enter+0x8c5/0x2380
[   71.507360]  do_syscall_64+0x39/0x80

We decoupled CQ locking from ->task_complete but haven't fixed up places
forcing locking for CQ overflows.

Fixes: ec26c225f0 ("io_uring: merge iopoll and normal completion paths")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-09-07 09:02:29 -06:00
Pavel Begunkov 45500dc4e0 io_uring: break out of iowq iopoll on teardown
io-wq will retry iopoll even when it failed with -EAGAIN. If that
races with task exit, which sets TIF_NOTIFY_SIGNAL for all its workers,
such workers might potentially infinitely spin retrying iopoll again and
again and each time failing on some allocation / waiting / etc. Don't
keep spinning if io-wq is dying.

Fixes: 561fb04a6a ("io_uring: replace workqueue usage with io-wq")
Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-09-07 09:02:27 -06:00
Matteo Rizzo 76d3ccecfa io_uring: add a sysctl to disable io_uring system-wide
Introduce a new sysctl (io_uring_disabled) which can be either 0, 1, or
2. When 0 (the default), all processes are allowed to create io_uring
instances, which is the current behavior.  When 1, io_uring creation is
disabled (io_uring_setup() will fail with -EPERM) for unprivileged
processes not in the kernel.io_uring_group group.  When 2, calls to
io_uring_setup() fail with -EPERM regardless of privilege.

Signed-off-by: Matteo Rizzo <matteorizzo@google.com>
[JEM: modified to add io_uring_group]
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Link: https://lore.kernel.org/r/x49y1i42j1z.fsf@segfault.boston.devel.redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-09-05 08:34:07 -06:00
Jens Axboe 32f5dea040 io_uring/fdinfo: only print ->sq_array[] if it's there
If a ring is setup with IORING_SETUP_NO_SQARRAY, then we don't have
the SQ array. Don't try to dump info from it through fdinfo if that
is the case.

Reported-by: syzbot+216e2ea6e0bf4a0acdd7@syzkaller.appspotmail.com
Fixes: 2af89abda7 ("io_uring: add option to remove SQ indirection")
Reviewed-by: Gabriel Krisman Bertazi <krisman@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-09-01 15:08:29 -06:00
Ming Lei b484a40dc1 io_uring: fix IO hang in io_wq_put_and_exit from do_exit()
io_wq_put_and_exit() is called from do_exit(), but all FIXED_FILE requests
in io_wq aren't canceled in io_uring_cancel_generic() called from do_exit().
Meantime io_wq IO code path may share resource with normal iopoll code
path.

So if any HIPRI request is submittd via io_wq, this request may not get resouce
for moving on, given iopoll isn't possible in io_wq_put_and_exit().

The issue can be triggered when terminating 't/io_uring -n4 /dev/nullb0'
with default null_blk parameters.

Fix it by always cancelling all requests in io_wq by adding helper of
io_uring_cancel_wq(), and this way is reasonable because io_wq destroying
follows canceling requests immediately.

Closes: https://lore.kernel.org/linux-block/3893581.1691785261@warthog.procyon.org.uk/
Reported-by: David Howells <dhowells@redhat.com>
Cc: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20230901134916.2415386-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-09-01 07:54:06 -06:00
Gabriel Krisman Bertazi bd6fc5da4c io_uring: Don't set affinity on a dying sqpoll thread
Syzbot reported a null-ptr-deref of sqd->thread inside
io_sqpoll_wq_cpu_affinity.  It turns out the sqd->thread can go away
from under us during io_uring_register, in case the process gets a
fatal signal during io_uring_register.

It is not particularly hard to hit the race, and while I am not sure
this is the exact case hit by syzbot, it solves it.  Finally, checking
->thread is enough to close the race because we locked sqd while
"parking" the thread, thus preventing it from going away.

I reproduced it fairly consistently with a program that does:

int main(void) {
  ...
  io_uring_queue_init(RING_LEN, &ring1, IORING_SETUP_SQPOLL);
  while (1) {
    io_uring_register_iowq_aff(ring, 1, &mask);
  }
}

Executed in a loop with timeout to trigger SIGTERM:
  while true; do timeout 1 /a.out ; done

This will hit the following BUG() in very few attempts.

BUG: kernel NULL pointer dereference, address: 00000000000007a8
PGD 800000010e949067 P4D 800000010e949067 PUD 10e46e067 PMD 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 0 PID: 15715 Comm: dead-sqpoll Not tainted 6.5.0-rc7-next-20230825-g193296236fa0-dirty #23
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
RIP: 0010:io_sqpoll_wq_cpu_affinity+0x27/0x70
Code: 90 90 90 0f 1f 44 00 00 55 53 48 8b 9f 98 03 00 00 48 85 db 74 4f
48 89 df 48 89 f5 e8 e2 f8 ff ff 48 8b 43 38 48 85 c0 74 22 <48> 8b b8
a8 07 00 00 48 89 ee e8 ba b1 00 00 48 89 df 89 c5 e8 70
RSP: 0018:ffffb04040ea7e70 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff93c010749e40 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffffa7653331 RDI: 00000000ffffffff
RBP: ffffb04040ea7eb8 R08: 0000000000000000 R09: c0000000ffffdfff
R10: ffff93c01141b600 R11: ffffb04040ea7d18 R12: ffff93c00ea74840
R13: 0000000000000011 R14: 0000000000000000 R15: ffff93c00ea74800
FS:  00007fb7c276ab80(0000) GS:ffff93c36f200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000007a8 CR3: 0000000111634003 CR4: 0000000000370ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ? __die_body+0x1a/0x60
 ? page_fault_oops+0x154/0x440
 ? do_user_addr_fault+0x174/0x7b0
 ? exc_page_fault+0x63/0x140
 ? asm_exc_page_fault+0x22/0x30
 ? io_sqpoll_wq_cpu_affinity+0x27/0x70
 __io_register_iowq_aff+0x2b/0x60
 __io_uring_register+0x614/0xa70
 __x64_sys_io_uring_register+0xaa/0x1a0
 do_syscall_64+0x3a/0x90
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8
RIP: 0033:0x7fb7c226fec9
Code: 2e 00 b8 ca 00 00 00 0f 05 eb a5 66 0f 1f 44 00 00 48 89 f8 48 89
f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01
f0 ff ff 73 01 c3 48 8b 0d 97 7f 2d 00 f7 d8 64 89 01 48
RSP: 002b:00007ffe2c0674f8 EFLAGS: 00000246 ORIG_RAX: 00000000000001ab
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb7c226fec9
RDX: 00007ffe2c067530 RSI: 0000000000000011 RDI: 0000000000000003
RBP: 00007ffe2c0675d0 R08: 00007ffe2c067550 R09: 00007ffe2c067550
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe2c067750 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Modules linked in:
CR2: 00000000000007a8
---[ end trace 0000000000000000 ]---

Reported-by: syzbot+c74fea926a78b8a91042@syzkaller.appspotmail.com
Fixes: ebdfefc09c ("io_uring/sqpoll: fix io-wq affinity when IORING_SETUP_SQPOLL is used")
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://lore.kernel.org/r/87v8cybuo6.fsf@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-08-30 09:53:44 -06:00
Linus Torvalds c1b7fcf3f6 for-6.6/io_uring-2023-08-28
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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
  ...
2023-08-29 20:11:33 -07:00
Linus Torvalds b96a3e9142 - Some swap cleanups from Ma Wupeng ("fix WARN_ON in add_to_avail_list")
- Peter Xu has a series (mm/gup: Unify hugetlb, speed up thp") which
   reduces the special-case code for handling hugetlb pages in GUP.  It
   also speeds up GUP handling of transparent hugepages.
 
 - Peng Zhang provides some maple tree speedups ("Optimize the fast path
   of mas_store()").
 
 - Sergey Senozhatsky has improved te performance of zsmalloc during
   compaction (zsmalloc: small compaction improvements").
 
 - Domenico Cerasuolo has developed additional selftest code for zswap
   ("selftests: cgroup: add zswap test program").
 
 - xu xin has doe some work on KSM's handling of zero pages.  These
   changes are mainly to enable the user to better understand the
   effectiveness of KSM's treatment of zero pages ("ksm: support tracking
   KSM-placed zero-pages").
 
 - Jeff Xu has fixes the behaviour of memfd's
   MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED sysctl ("mm/memfd: fix sysctl
   MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED").
 
 - David Howells has fixed an fscache optimization ("mm, netfs, fscache:
   Stop read optimisation when folio removed from pagecache").
 
 - Axel Rasmussen has given userfaultfd the ability to simulate memory
   poisoning ("add UFFDIO_POISON to simulate memory poisoning with UFFD").
 
 - Miaohe Lin has contributed some routine maintenance work on the
   memory-failure code ("mm: memory-failure: remove unneeded PageHuge()
   check").
 
 - Peng Zhang has contributed some maintenance work on the maple tree
   code ("Improve the validation for maple tree and some cleanup").
 
 - Hugh Dickins has optimized the collapsing of shmem or file pages into
   THPs ("mm: free retracted page table by RCU").
 
 - Jiaqi Yan has a patch series which permits us to use the healthy
   subpages within a hardware poisoned huge page for general purposes
   ("Improve hugetlbfs read on HWPOISON hugepages").
 
 - Kemeng Shi has done some maintenance work on the pagetable-check code
   ("Remove unused parameters in page_table_check").
 
 - More folioification work from Matthew Wilcox ("More filesystem folio
   conversions for 6.6"), ("Followup folio conversions for zswap").  And
   from ZhangPeng ("Convert several functions in page_io.c to use a
   folio").
 
 - page_ext cleanups from Kemeng Shi ("minor cleanups for page_ext").
 
 - Baoquan He has converted some architectures to use the GENERIC_IOREMAP
   ioremap()/iounmap() code ("mm: ioremap: Convert architectures to take
   GENERIC_IOREMAP way").
 
 - Anshuman Khandual has optimized arm64 tlb shootdown ("arm64: support
   batched/deferred tlb shootdown during page reclamation/migration").
 
 - Better maple tree lockdep checking from Liam Howlett ("More strict
   maple tree lockdep").  Liam also developed some efficiency improvements
   ("Reduce preallocations for maple tree").
 
 - Cleanup and optimization to the secondary IOMMU TLB invalidation, from
   Alistair Popple ("Invalidate secondary IOMMU TLB on permission
   upgrade").
 
 - Ryan Roberts fixes some arm64 MM selftest issues ("selftests/mm fixes
   for arm64").
 
 - Kemeng Shi provides some maintenance work on the compaction code ("Two
   minor cleanups for compaction").
 
 - Some reduction in mmap_lock pressure from Matthew Wilcox ("Handle most
   file-backed faults under the VMA lock").
 
 - Aneesh Kumar contributes code to use the vmemmap optimization for DAX
   on ppc64, under some circumstances ("Add support for DAX vmemmap
   optimization for ppc64").
 
 - page-ext cleanups from Kemeng Shi ("add page_ext_data to get client
   data in page_ext"), ("minor cleanups to page_ext header").
 
 - Some zswap cleanups from Johannes Weiner ("mm: zswap: three
   cleanups").
 
 - kmsan cleanups from ZhangPeng ("minor cleanups for kmsan").
 
 - VMA handling cleanups from Kefeng Wang ("mm: convert to
   vma_is_initial_heap/stack()").
 
 - DAMON feature work from SeongJae Park ("mm/damon/sysfs-schemes:
   implement DAMOS tried total bytes file"), ("Extend DAMOS filters for
   address ranges and DAMON monitoring targets").
 
 - Compaction work from Kemeng Shi ("Fixes and cleanups to compaction").
 
 - Liam Howlett has improved the maple tree node replacement code
   ("maple_tree: Change replacement strategy").
 
 - ZhangPeng has a general code cleanup - use the K() macro more widely
   ("cleanup with helper macro K()").
 
 - Aneesh Kumar brings memmap-on-memory to ppc64 ("Add support for memmap
   on memory feature on ppc64").
 
 - pagealloc cleanups from Kemeng Shi ("Two minor cleanups for pcp list
   in page_alloc"), ("Two minor cleanups for get pageblock migratetype").
 
 - Vishal Moola introduces a memory descriptor for page table tracking,
   "struct ptdesc" ("Split ptdesc from struct page").
 
 - memfd selftest maintenance work from Aleksa Sarai ("memfd: cleanups
   for vm.memfd_noexec").
 
 - MM include file rationalization from Hugh Dickins ("arch: include
   asm/cacheflush.h in asm/hugetlb.h").
 
 - THP debug output fixes from Hugh Dickins ("mm,thp: fix sloppy text
   output").
 
 - kmemleak improvements from Xiaolei Wang ("mm/kmemleak: use
   object_cache instead of kmemleak_initialized").
 
 - More folio-related cleanups from Matthew Wilcox ("Remove _folio_dtor
   and _folio_order").
 
 - A VMA locking scalability improvement from Suren Baghdasaryan
   ("Per-VMA lock support for swap and userfaults").
 
 - pagetable handling cleanups from Matthew Wilcox ("New page table range
   API").
 
 - A batch of swap/thp cleanups from David Hildenbrand ("mm/swap: stop
   using page->private on tail pages for THP_SWAP + cleanups").
 
 - Cleanups and speedups to the hugetlb fault handling from Matthew
   Wilcox ("Change calling convention for ->huge_fault").
 
 - Matthew Wilcox has also done some maintenance work on the MM subsystem
   documentation ("Improve mm documentation").
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Merge tag 'mm-stable-2023-08-28-18-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - Some swap cleanups from Ma Wupeng ("fix WARN_ON in
   add_to_avail_list")

 - Peter Xu has a series (mm/gup: Unify hugetlb, speed up thp") which
   reduces the special-case code for handling hugetlb pages in GUP. It
   also speeds up GUP handling of transparent hugepages.

 - Peng Zhang provides some maple tree speedups ("Optimize the fast path
   of mas_store()").

 - Sergey Senozhatsky has improved te performance of zsmalloc during
   compaction (zsmalloc: small compaction improvements").

 - Domenico Cerasuolo has developed additional selftest code for zswap
   ("selftests: cgroup: add zswap test program").

 - xu xin has doe some work on KSM's handling of zero pages. These
   changes are mainly to enable the user to better understand the
   effectiveness of KSM's treatment of zero pages ("ksm: support
   tracking KSM-placed zero-pages").

 - Jeff Xu has fixes the behaviour of memfd's
   MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED sysctl ("mm/memfd: fix sysctl
   MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED").

 - David Howells has fixed an fscache optimization ("mm, netfs, fscache:
   Stop read optimisation when folio removed from pagecache").

 - Axel Rasmussen has given userfaultfd the ability to simulate memory
   poisoning ("add UFFDIO_POISON to simulate memory poisoning with
   UFFD").

 - Miaohe Lin has contributed some routine maintenance work on the
   memory-failure code ("mm: memory-failure: remove unneeded PageHuge()
   check").

 - Peng Zhang has contributed some maintenance work on the maple tree
   code ("Improve the validation for maple tree and some cleanup").

 - Hugh Dickins has optimized the collapsing of shmem or file pages into
   THPs ("mm: free retracted page table by RCU").

 - Jiaqi Yan has a patch series which permits us to use the healthy
   subpages within a hardware poisoned huge page for general purposes
   ("Improve hugetlbfs read on HWPOISON hugepages").

 - Kemeng Shi has done some maintenance work on the pagetable-check code
   ("Remove unused parameters in page_table_check").

 - More folioification work from Matthew Wilcox ("More filesystem folio
   conversions for 6.6"), ("Followup folio conversions for zswap"). And
   from ZhangPeng ("Convert several functions in page_io.c to use a
   folio").

 - page_ext cleanups from Kemeng Shi ("minor cleanups for page_ext").

 - Baoquan He has converted some architectures to use the
   GENERIC_IOREMAP ioremap()/iounmap() code ("mm: ioremap: Convert
   architectures to take GENERIC_IOREMAP way").

 - Anshuman Khandual has optimized arm64 tlb shootdown ("arm64: support
   batched/deferred tlb shootdown during page reclamation/migration").

 - Better maple tree lockdep checking from Liam Howlett ("More strict
   maple tree lockdep"). Liam also developed some efficiency
   improvements ("Reduce preallocations for maple tree").

 - Cleanup and optimization to the secondary IOMMU TLB invalidation,
   from Alistair Popple ("Invalidate secondary IOMMU TLB on permission
   upgrade").

 - Ryan Roberts fixes some arm64 MM selftest issues ("selftests/mm fixes
   for arm64").

 - Kemeng Shi provides some maintenance work on the compaction code
   ("Two minor cleanups for compaction").

 - Some reduction in mmap_lock pressure from Matthew Wilcox ("Handle
   most file-backed faults under the VMA lock").

 - Aneesh Kumar contributes code to use the vmemmap optimization for DAX
   on ppc64, under some circumstances ("Add support for DAX vmemmap
   optimization for ppc64").

 - page-ext cleanups from Kemeng Shi ("add page_ext_data to get client
   data in page_ext"), ("minor cleanups to page_ext header").

 - Some zswap cleanups from Johannes Weiner ("mm: zswap: three
   cleanups").

 - kmsan cleanups from ZhangPeng ("minor cleanups for kmsan").

 - VMA handling cleanups from Kefeng Wang ("mm: convert to
   vma_is_initial_heap/stack()").

 - DAMON feature work from SeongJae Park ("mm/damon/sysfs-schemes:
   implement DAMOS tried total bytes file"), ("Extend DAMOS filters for
   address ranges and DAMON monitoring targets").

 - Compaction work from Kemeng Shi ("Fixes and cleanups to compaction").

 - Liam Howlett has improved the maple tree node replacement code
   ("maple_tree: Change replacement strategy").

 - ZhangPeng has a general code cleanup - use the K() macro more widely
   ("cleanup with helper macro K()").

 - Aneesh Kumar brings memmap-on-memory to ppc64 ("Add support for
   memmap on memory feature on ppc64").

 - pagealloc cleanups from Kemeng Shi ("Two minor cleanups for pcp list
   in page_alloc"), ("Two minor cleanups for get pageblock
   migratetype").

 - Vishal Moola introduces a memory descriptor for page table tracking,
   "struct ptdesc" ("Split ptdesc from struct page").

 - memfd selftest maintenance work from Aleksa Sarai ("memfd: cleanups
   for vm.memfd_noexec").

 - MM include file rationalization from Hugh Dickins ("arch: include
   asm/cacheflush.h in asm/hugetlb.h").

 - THP debug output fixes from Hugh Dickins ("mm,thp: fix sloppy text
   output").

 - kmemleak improvements from Xiaolei Wang ("mm/kmemleak: use
   object_cache instead of kmemleak_initialized").

 - More folio-related cleanups from Matthew Wilcox ("Remove _folio_dtor
   and _folio_order").

 - A VMA locking scalability improvement from Suren Baghdasaryan
   ("Per-VMA lock support for swap and userfaults").

 - pagetable handling cleanups from Matthew Wilcox ("New page table
   range API").

 - A batch of swap/thp cleanups from David Hildenbrand ("mm/swap: stop
   using page->private on tail pages for THP_SWAP + cleanups").

 - Cleanups and speedups to the hugetlb fault handling from Matthew
   Wilcox ("Change calling convention for ->huge_fault").

 - Matthew Wilcox has also done some maintenance work on the MM
   subsystem documentation ("Improve mm documentation").

* tag 'mm-stable-2023-08-28-18-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (489 commits)
  maple_tree: shrink struct maple_tree
  maple_tree: clean up mas_wr_append()
  secretmem: convert page_is_secretmem() to folio_is_secretmem()
  nios2: fix flush_dcache_page() for usage from irq context
  hugetlb: add documentation for vma_kernel_pagesize()
  mm: add orphaned kernel-doc to the rst files.
  mm: fix clean_record_shared_mapping_range kernel-doc
  mm: fix get_mctgt_type() kernel-doc
  mm: fix kernel-doc warning from tlb_flush_rmaps()
  mm: remove enum page_entry_size
  mm: allow ->huge_fault() to be called without the mmap_lock held
  mm: move PMD_ORDER to pgtable.h
  mm: remove checks for pte_index
  memcg: remove duplication detection for mem_cgroup_uncharge_swap
  mm/huge_memory: work on folio->swap instead of page->private when splitting folio
  mm/swap: inline folio_set_swap_entry() and folio_swap_entry()
  mm/swap: use dedicated entry for swap in folio
  mm/swap: stop using page->private on tail pages for THP_SWAP
  selftests/mm: fix WARNING comparing pointer to 0
  selftests: cgroup: fix test_kmem_memcg_deletion kernel mem check
  ...
2023-08-29 14:25:26 -07:00
Linus Torvalds 6016fc9162 New code for 6.6:
* Make large writes to the page cache fill sparse parts of the cache
    with large folios, then use large memcpy calls for the large folio.
  * Track the per-block dirty state of each large folio so that a
    buffered write to a single byte on a large folio does not result in a
    (potentially) multi-megabyte writeback IO.
  * Allow some directio completions to be performed in the initiating
    task's context instead of punting through a workqueue.  This will
    reduce latency for some io_uring requests.
 
 Signed-off-by: Darrick J. Wong <djwong@kernel.org>
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Merge tag 'iomap-6.6-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull iomap updates from Darrick Wong:
 "We've got some big changes for this release -- I'm very happy to be
  landing willy's work to enable large folios for the page cache for
  general read and write IOs when the fs can make contiguous space
  allocations, and Ritesh's work to track sub-folio dirty state to
  eliminate the write amplification problems inherent in using large
  folios.

  As a bonus, io_uring can now process write completions in the caller's
  context instead of bouncing through a workqueue, which should reduce
  io latency dramatically. IOWs, XFS should see a nice performance bump
  for both IO paths.

  Summary:

   - Make large writes to the page cache fill sparse parts of the cache
     with large folios, then use large memcpy calls for the large folio.

   - Track the per-block dirty state of each large folio so that a
     buffered write to a single byte on a large folio does not result in
     a (potentially) multi-megabyte writeback IO.

   - Allow some directio completions to be performed in the initiating
     task's context instead of punting through a workqueue. This will
     reduce latency for some io_uring requests"

* tag 'iomap-6.6-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (26 commits)
  iomap: support IOCB_DIO_CALLER_COMP
  io_uring/rw: add write support for IOCB_DIO_CALLER_COMP
  fs: add IOCB flags related to passing back dio completions
  iomap: add IOMAP_DIO_INLINE_COMP
  iomap: only set iocb->private for polled bio
  iomap: treat a write through cache the same as FUA
  iomap: use an unsigned type for IOMAP_DIO_* defines
  iomap: cleanup up iomap_dio_bio_end_io()
  iomap: Add per-block dirty state tracking to improve performance
  iomap: Allocate ifs in ->write_begin() early
  iomap: Refactor iomap_write_delalloc_punch() function out
  iomap: Use iomap_punch_t typedef
  iomap: Fix possible overflow condition in iomap_write_delalloc_scan
  iomap: Add some uptodate state handling helpers for ifs state bitmap
  iomap: Drop ifs argument from iomap_set_range_uptodate()
  iomap: Rename iomap_page to iomap_folio_state and others
  iomap: Copy larger chunks from userspace
  iomap: Create large folios in the buffered write path
  filemap: Allow __filemap_get_folio to allocate large folios
  filemap: Add fgf_t typedef
  ...
2023-08-28 11:59:52 -07:00
Linus Torvalds de16588a77 v6.6-vfs.misc
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Merge tag 'v6.6-vfs.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull misc vfs updates from Christian Brauner:
 "This contains the usual miscellaneous features, cleanups, and fixes
  for vfs and individual filesystems.

  Features:

   - Block mode changes on symlinks and rectify our broken semantics

   - Report file modifications via fsnotify() for splice

   - Allow specifying an explicit timeout for the "rootwait" kernel
     command line option. This allows to timeout and reboot instead of
     always waiting indefinitely for the root device to show up

   - Use synchronous fput for the close system call

  Cleanups:

   - Get rid of open-coded lockdep workarounds for async io submitters
     and replace it all with a single consolidated helper

   - Simplify epoll allocation helper

   - Convert simple_write_begin and simple_write_end to use a folio

   - Convert page_cache_pipe_buf_confirm() to use a folio

   - Simplify __range_close to avoid pointless locking

   - Disable per-cpu buffer head cache for isolated cpus

   - Port ecryptfs to kmap_local_page() api

   - Remove redundant initialization of pointer buf in pipe code

   - Unexport the d_genocide() function which is only used within core
     vfs

   - Replace printk(KERN_ERR) and WARN_ON() with WARN()

  Fixes:

   - Fix various kernel-doc issues

   - Fix refcount underflow for eventfds when used as EFD_SEMAPHORE

   - Fix a mainly theoretical issue in devpts

   - Check the return value of __getblk() in reiserfs

   - Fix a racy assert in i_readcount_dec

   - Fix integer conversion issues in various functions

   - Fix LSM security context handling during automounts that prevented
     NFS superblock sharing"

* tag 'v6.6-vfs.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (39 commits)
  cachefiles: use kiocb_{start,end}_write() helpers
  ovl: use kiocb_{start,end}_write() helpers
  aio: use kiocb_{start,end}_write() helpers
  io_uring: use kiocb_{start,end}_write() helpers
  fs: create kiocb_{start,end}_write() helpers
  fs: add kerneldoc to file_{start,end}_write() helpers
  io_uring: rename kiocb_end_write() local helper
  splice: Convert page_cache_pipe_buf_confirm() to use a folio
  libfs: Convert simple_write_begin and simple_write_end to use a folio
  fs/dcache: Replace printk and WARN_ON by WARN
  fs/pipe: remove redundant initialization of pointer buf
  fs: Fix kernel-doc warnings
  devpts: Fix kernel-doc warnings
  doc: idmappings: fix an error and rephrase a paragraph
  init: Add support for rootwait timeout parameter
  vfs: fix up the assert in i_readcount_dec
  fs: Fix one kernel-doc comment
  docs: filesystems: idmappings: clarify from where idmappings are taken
  fs/buffer.c: disable per-CPU buffer_head cache for isolated CPUs
  vfs, security: Fix automount superblock LSM init problem, preventing NFS sb sharing
  ...
2023-08-28 10:17:14 -07:00