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Today blk_queue_enter() and __bio_queue_enter() return -EBUSY for the
nowait code path. This is not correct: they should return -EAGAIN
instead.
This problem was detected by fio. The following command exposed the
above problem:
t/io_uring -p0 -d128 -b4096 -s32 -c32 -F1 -B0 -R0 -X1 -n24 -P1 -u1 -O0 /dev/ng0n1
By applying the patch, the retry case is handled correctly in the slow
path.
Signed-off-by: Stefan Roesch <shr@fb.com>
Fixes: bfd343aa1718 ("blk-mq: don't wait in blk_mq_queue_enter() if __GFP_WAIT isn't set")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We're missing TIMED_OUT and RESV. Particularly the former is handy
for debugging, let's get them added.
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull NVMe fixes from Christoph:
"nvme fixes for Linux 6.1
- fix a use after free in nvmet (Bart Van Assche)
- fix a use after free when detecting digest errors (Sagi Grimberg)
- fix regression that causes sporadic TCP requests to time out
(Sagi Grimberg)
- fix two off by ones errors in the nvmet ZNS support
(Dennis Maisenbacher)
- requeue aen after firmware activation (Keith Busch)"
* tag 'nvme-6.0-2022-09-08' of git://git.infradead.org/nvme:
nvme: requeue aen after firmware activation
nvmet: fix mar and mor off-by-one errors
nvme-tcp: fix regression that causes sporadic requests to time out
nvme-tcp: fix UAF when detecting digest errors
nvmet: fix a use-after-free
Commit b9684a71fca7 ("block, loop: support partitions without scanning")
adds GD_SUPPRESS_PART_SCAN for replacing part function of
GENHD_FL_NO_PART. But looks blk_add_partitions() is missed, since
loop doesn't want to add partitions if GENHD_FL_NO_PART was set.
And it causes regression on libblockdev (as called from udisks) which
operates with the LO_FLAGS_PARTSCAN.
Fixes the issue by not adding partitions if GD_SUPPRESS_PART_SCAN is
set.
Fixes: b9684a71fca7 ("block, loop: support partitions without scanning")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220823103819.395776-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The driver prevents async event work while handling a processing paused
event, but someone needs to restart it after the controller returns to a
live state.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216400
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add documentation for ublk subsystem. It was supposed to be documented when
merging the driver, but missing at that time.
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Richard W.M. Jones <rjones@redhat.com>
Cc: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: ZiyangZhang <ZiyangZhang@linux.alibaba.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
[axboe: correct MAINTAINERS addition]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Maximum Active Resources (MAR) and Maximum Open Resources (MOR) are 0's
based vales where a value of 0xffffffff indicates that there is no limit.
Decrement the values that are returned by bdev_max_open_zones and
bdev_max_active_zones as the block layer helpers are not 0's based.
A 0 returned by the block layer helpers indicates no limit, thus convert
it to 0xffffffff (U32_MAX).
Fixes: aaf2e048af27 ("nvmet: add ZBD over ZNS backend support")
Suggested-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Dennis Maisenbacher <dennis.maisenbacher@wdc.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull NVMe fixes from Christoph:
"nvme fixes for Linux 6.0
- error handling fix for the new auth code (Hannes Reinecke)
- fix unhandled tcp states in nvmet_tcp_state_change (Maurizio Lombardi)
- add NVME_QUIRK_BOGUS_NID for Lexar NM610 (Shyamin Ayesh)"
* tag 'nvme-6.0-2022-09-01' of git://git.infradead.org/nvme:
nvmet-tcp: fix unhandled tcp states in nvmet_tcp_state_change()
nvmet-auth: add missing goto in nvmet_setup_auth()
nvme-pci: add NVME_QUIRK_BOGUS_NID for Lexar NM610
When we queue requests, we strive to batch as much as possible and also
signal the network stack that more data is about to be sent over a socket
with MSG_SENDPAGE_NOTLAST. This flag looks at the pending requests queued
as well as queue->more_requests that is derived from the block layer
last-in-batch indication.
We set more_request=true when we flush the request directly from
.queue_rq submission context (in nvme_tcp_send_all), however this is
wrongly assuming that no other requests may be queued during the
execution of nvme_tcp_send_all.
Due to this, a race condition may happen where:
1. request X is queued as !last-in-batch
2. request X submission context calls nvme_tcp_send_all directly
3. nvme_tcp_send_all is preempted and schedules to a different cpu
4. request Y is queued as last-in-batch
5. nvme_tcp_send_all context sends request X+Y, however signals for
both MSG_SENDPAGE_NOTLAST because queue->more_requests=true.
==> none of the requests is pushed down to the wire as the network
stack is waiting for more data, both requests timeout.
To fix this, we eliminate queue->more_requests and only rely on
the queue req_list and send_list to be not-empty.
Fixes: 122e5b9f3d37 ("nvme-tcp: optimize network stack with setting msg flags according to batch size")
Reported-by: Jonathan Nicklin <jnicklin@blockbridge.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Tested-by: Jonathan Nicklin <jnicklin@blockbridge.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull MD fixes from Song:
"1. Fix for clustered raid, by Guoqing Jiang.
2. req_op fix, by Bart Van Assche.
3. Fix race condition in raid recreate, by David Sloan."
* 'md-fixes' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md:
md: call __md_stop_writes in md_stop
Revert "md-raid: destroy the bitmap after destroying the thread"
md: Flush workqueue md_rdev_misc_wq in md_alloc()
md/raid10: Fix the data type of an r10_sync_page_io() argument
TCP_FIN_WAIT2 and TCP_LAST_ACK were not handled, the connection is closing
so we can ignore them and avoid printing the "unhandled state"
warning message.
[ 1298.852386] nvmet_tcp: queue 2 unhandled state 5
[ 1298.879112] nvmet_tcp: queue 7 unhandled state 5
[ 1298.884253] nvmet_tcp: queue 8 unhandled state 5
[ 1298.889475] nvmet_tcp: queue 9 unhandled state 5
v2: Do not call nvmet_tcp_schedule_release_queue(), just ignore
the fin_wait2 and last_ack states.
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
We should also bail from the io_work loop when we set rd_enabled to true,
so we don't attempt to read data from the socket when the TCP stream is
already out-of-sync or corrupted.
Fixes: 3f2304f8c6d6 ("nvme-tcp: add NVMe over TCP host driver")
Reported-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The userspace can configure a loop using an ioctl call, wherein
a configuration of type loop_config is passed (see lo_ioctl()'s
case on line 1550 of drivers/block/loop.c). This proceeds to call
loop_configure() which in turn calls loop_set_status_from_info()
(see line 1050 of loop.c), passing &config->info which is of type
loop_info64*. This function then sets the appropriate values, like
the offset.
loop_device has lo_offset of type loff_t (see line 52 of loop.c),
which is typdef-chained to long long, whereas loop_info64 has
lo_offset of type __u64 (see line 56 of include/uapi/linux/loop.h).
The function directly copies offset from info to the device as
follows (See line 980 of loop.c):
lo->lo_offset = info->lo_offset;
This results in an overflow, which triggers a warning in iomap_iter()
due to a call to iomap_iter_done() which has:
WARN_ON_ONCE(iter->iomap.offset > iter->pos);
Thus, check for negative value during loop_set_status_from_info().
Bug report: https://syzkaller.appspot.com/bug?id=c620fe14aac810396d3c3edc9ad73848bf69a29e
Reported-and-tested-by: syzbot+a8e049cd3abd342936b6@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Siddh Raman Pant <code@siddh.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220823160810.181275-1-code@siddh.me
Signed-off-by: Jens Axboe <axboe@kernel.dk>
From the link [1], we can see raid1d was running even after the path
raid_dtr -> md_stop -> __md_stop.
Let's stop write first in destructor to align with normal md-raid to
fix the KASAN issue.
[1]. https://lore.kernel.org/linux-raid/CAPhsuW5gc4AakdGNdF8ubpezAuDLFOYUO_sfMZcec6hQFm8nhg@mail.gmail.com/T/#m7f12bf90481c02c6d2da68c64aeed4779b7df74a
Fixes: 48df498daf62 ("md: move bitmap_destroy to the beginning of __md_stop")
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
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