linux-toradex.git/io_uring, branch v6.3-rc5

Merge tag 'io_uring-6.3-2023-03-30' of git://git.kernel.dk/linux

2023-03-31T19:30:13+00:00

Pull io_uring fixes from Jens Axboe:

 - Fix a regression with the poll retry, introduced in this merge window
   (me)

 - Fix a regression with the alloc cache not decrementing the member
   count on removal. Also a regression from this merge window (Pavel)

 - Fix race around rsrc node grabbing (Pavel)

* tag 'io_uring-6.3-2023-03-30' of git://git.kernel.dk/linux:
  io_uring: fix poll/netmsg alloc caches
  io_uring/rsrc: fix rogue rsrc node grabbing
  io_uring/poll: clear single/double poll flags on poll arming

io_uring: fix poll/netmsg alloc caches

2023-03-30T12:53:42+00:00

We increase cache->nr_cached when we free into the cache but don't
decrease when we take from it, so in some time we'll get an empty
cache with cache->nr_cached larger than IO_ALLOC_CACHE_MAX, that fails
io_alloc_cache_put() and effectively disables caching.

Fixes: 9b797a37c4bd8 ("io_uring: add abstraction around apoll cache")
Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov 
Signed-off-by: Jens Axboe

io_uring/rsrc: fix rogue rsrc node grabbing

2023-03-29T15:23:46+00:00

We should not be looking at ctx->rsrc_node and anyhow modifying the node
without holding uring_lock, grabbing references in such a way is not
safe either.

Cc: stable@vger.kernel.org
Fixes: 5106dd6e74ab6 ("io_uring: propagate issue_flags state down to file assignment")
Signed-off-by: Pavel Begunkov 
Link: https://lore.kernel.org/r/1202ede2d7bb90136e3482b2b84aad9ed483e5d6.1680098433.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe

io_uring/poll: clear single/double poll flags on poll arming

2023-03-28T13:09:01+00:00

Unless we have at least one entry queued, then don't call into
io_poll_remove_entries(). Normally this isn't possible, but if we
retry poll then we can have ->nr_entries cleared again as we're
setting it up. If this happens for a poll retry, then we'll still have
at least REQ_F_SINGLE_POLL set. io_poll_remove_entries() then thinks
it has entries to remove.

Clear REQ_F_SINGLE_POLL and REQ_F_DOUBLE_POLL unconditionally when
arming a poll request.

Fixes: c16bda37594f ("io_uring/poll: allow some retries for poll triggering spuriously")
Cc: stable@vger.kernel.org
Reported-by: Pengfei Xu 
Signed-off-by: Jens Axboe

Merge tag 'block-6.3-2023-03-24' of git://git.kernel.dk/linux

2023-03-24T21:10:39+00:00

Pull block fixes from Jens Axboe:

 - NVMe pull request via Christoph:
     - Send Identify with CNS 06h only to I/O controllers (Martin
       George)
     - Fix nvme_tcp_term_pdu to match spec (Caleb Sander)

 - Pass in issue_flags for uring_cmd, so the end_io handlers don't need
   to assume what the right context is (me)

 - Fix for ublk, marking it as LIVE before adding it to avoid races on
   the initial IO (Ming)

* tag 'block-6.3-2023-03-24' of git://git.kernel.dk/linux:
  nvme-tcp: fix nvme_tcp_term_pdu to match spec
  nvme: send Identify with CNS 06h only to I/O controllers
  block/io_uring: pass in issue_flags for uring_cmd task_work handling
  block: ublk_drv: mark device as LIVE before adding disk

io_uring/rsrc: fix null-ptr-deref in io_file_bitmap_get()

2023-03-22T17:04:55+00:00

When fixed files are unregistered, file_alloc_end and alloc_hint
are not cleared. This can later cause a NULL pointer dereference in
io_file_bitmap_get() if auto index selection is enabled via
IORING_FILE_INDEX_ALLOC:

[    6.519129] BUG: kernel NULL pointer dereference, address: 0000000000000000
[...]
[    6.541468] RIP: 0010:_find_next_zero_bit+0x1a/0x70
[...]
[    6.560906] Call Trace:
[    6.561322]  
[    6.561672]  io_file_bitmap_get+0x38/0x60
[    6.562281]  io_fixed_fd_install+0x63/0xb0
[    6.562851]  ? __pfx_io_socket+0x10/0x10
[    6.563396]  io_socket+0x93/0xf0
[    6.563855]  ? __pfx_io_socket+0x10/0x10
[    6.564411]  io_issue_sqe+0x5b/0x3d0
[    6.564914]  io_submit_sqes+0x1de/0x650
[    6.565452]  __do_sys_io_uring_enter+0x4fc/0xb20
[    6.566083]  ? __do_sys_io_uring_register+0x11e/0xd80
[    6.566779]  do_syscall_64+0x3c/0x90
[    6.567247]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
[...]

To fix the issue, set file alloc range and alloc_hint to zero after
file tables are freed.

Cc: stable@vger.kernel.org
Fixes: 4278a0deb1f6 ("io_uring: defer alloc_hint update to io_file_bitmap_set()")
Signed-off-by: Savino Dicanosa 
[axboe: add explicit bitmap == NULL check as well]
Signed-off-by: Jens Axboe

io_uring/net: avoid sending -ECONNABORTED on repeated connection requests

2023-03-21T02:44:45+00:00

Since io_uring does nonblocking connect requests, if we do two repeated
ones without having a listener, the second will get -ECONNABORTED rather
than the expected -ECONNREFUSED. Treat -ECONNABORTED like a normal retry
condition if we're nonblocking, if we haven't already seen it.

Cc: stable@vger.kernel.org
Fixes: 3fb1bd688172 ("io_uring/net: handle -EINPROGRESS correct for IORING_OP_CONNECT")
Link: https://github.com/axboe/liburing/issues/828
Reported-by: Hui, Chunyang 
Signed-off-by: Jens Axboe

block/io_uring: pass in issue_flags for uring_cmd task_work handling

2023-03-21T02:01:25+00:00

io_uring_cmd_done() currently assumes that the uring_lock is held
when invoked, and while it generally is, this is not guaranteed.
Pass in the issue_flags associated with it, so that we have
IO_URING_F_UNLOCKED available to be able to lock the CQ ring
appropriately when completing events.

Cc: stable@vger.kernel.org
Fixes: ee692a21e9bf ("fs,io_uring: add infrastructure for uring-cmd")
Signed-off-by: Jens Axboe

io_uring/rsrc: fix folio accounting

2023-03-16T15:32:18+00:00

| BUG: Bad page state in process kworker/u8:0  pfn:5c001
| page:00000000bfda61c8 refcount:0 mapcount:0 mapping:0000000000000000 index:0x20001 pfn:0x5c001
| head:0000000011409842 order:9 entire_mapcount:0 nr_pages_mapped:0 pincount:1
| anon flags: 0x3fffc00000b0004(uptodate|head|mappedtodisk|swapbacked|node=0|zone=0|lastcpupid=0xffff)
| raw: 03fffc0000000000 fffffc0000700001 ffffffff00700903 0000000100000000
| raw: 0000000000000200 0000000000000000 00000000ffffffff 0000000000000000
| head: 03fffc00000b0004 dead000000000100 dead000000000122 ffff00000a809dc1
| head: 0000000000020000 0000000000000000 00000000ffffffff 0000000000000000
| page dumped because: nonzero pincount
| CPU: 3 PID: 9 Comm: kworker/u8:0 Not tainted 6.3.0-rc2-00001-gc6811bf0cd87 #1
| Hardware name: linux,dummy-virt (DT)
| Workqueue: events_unbound io_ring_exit_work
| Call trace:
|  dump_backtrace+0x13c/0x208
|  show_stack+0x34/0x58
|  dump_stack_lvl+0x150/0x1a8
|  dump_stack+0x20/0x30
|  bad_page+0xec/0x238
|  free_tail_pages_check+0x280/0x350
|  free_pcp_prepare+0x60c/0x830
|  free_unref_page+0x50/0x498
|  free_compound_page+0xcc/0x100
|  free_transhuge_page+0x1f0/0x2b8
|  destroy_large_folio+0x80/0xc8
|  __folio_put+0xc4/0xf8
|  gup_put_folio+0xd0/0x250
|  unpin_user_page+0xcc/0x128
|  io_buffer_unmap+0xec/0x2c0
|  __io_sqe_buffers_unregister+0xa4/0x1e0
|  io_ring_exit_work+0x68c/0x1188
|  process_one_work+0x91c/0x1a58
|  worker_thread+0x48c/0xe30
|  kthread+0x278/0x2f0
|  ret_from_fork+0x10/0x20

Mark reports an issue with the recent patches coalescing compound pages
while registering them in io_uring. The reason is that we try to drop
excessive references with folio_put_refs(), but pages were acquired
with pin_user_pages(), which has extra accounting and so should be put
down with matching unpin_user_pages() or at least gup_put_folio().

As a fix unpin_user_pages() all but first page instead, and let's figure
out a better API after.

Fixes: 57bebf807e2abcf8 ("io_uring/rsrc: optimise registered huge pages")
Reported-by: Mark Rutland 
Reviewed-by: Jens Axboe 
Tested-by: Jens Axboe 
Signed-off-by: Pavel Begunkov 
Link: https://lore.kernel.org/r/10efd5507d6d1f05ea0f3c601830e08767e189bd.1678980230.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe

io_uring/msg_ring: let target know allocated index

2023-03-16T13:16:56+00:00

msg_ring requests transferring files support auto index selection via
IORING_FILE_INDEX_ALLOC, however they don't return the selected index
to the target ring and there is no other good way for the userspace to
know where is the receieved file.

Return the index for allocated slots and 0 otherwise, which is
consistent with other fixed file installing requests.

Cc: stable@vger.kernel.org # v6.0+
Fixes: e6130eba8a848 ("io_uring: add support for passing fixed file descriptors")
Signed-off-by: Pavel Begunkov 
Link: https://github.com/axboe/liburing/issues/809
Signed-off-by: Jens Axboe