Yu Kuai [Mon, 29 May 2023 13:11:00 +0000 (21:11 +0800)]
md/raid10: prevent soft lockup while flush writes
Currently, there is no limit for raid1/raid10 plugged bio. While flushing
writes, raid1 has cond_resched() while raid10 doesn't, and too many
writes can cause soft lockup.
Follow up soft lockup can be triggered easily with writeback test for
raid10 with ramdisks:
Fix the problem by adding cond_resched() to raid10 like what raid1 did.
Note that unlimited plugged bio still need to be optimized, for example,
in the case of lots of dirty pages writeback, this will take lots of
memory and io will spend a long time in plug, hence io latency is bad.
Li Nan [Fri, 2 Jun 2023 09:18:39 +0000 (17:18 +0800)]
md/raid10: fix io loss while replacement replace rdev
When removing a disk with replacement, the replacement will be used to
replace rdev. During this process, there is a brief window in which both
rdev and replacement are read as NULL in raid10_write_request(). This
will result in io not being submitted but it should be.
Fix it by reading replacement first and rdev later, meanwhile, use smp_mb()
to prevent memory reordering.
Fixes: 475b0321a4df ("md/raid10: writes should get directed to replacement as well as original.") Signed-off-by: Li Nan <linan122@huawei.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230602091839.743798-3-linan666@huaweicloud.com
Li Nan [Fri, 2 Jun 2023 09:18:38 +0000 (17:18 +0800)]
md/raid10: Do not add spare disk when recovery fails
In raid10_sync_request(), if data cannot be read from any disk for
recovery, it will go to 'giveup' and let 'chunks_skipped' + 1. After
multiple 'giveup', when 'chunks_skipped >= geo.raid_disks', it will
return 'max_sector', indicating that the recovery has been completed.
However, the recovery is just aborted and the data remains inconsistent.
Fix it by setting mirror->recovery_disabled, which will prevent the spare
disk from being added to this mirror. The same issue also exists during
resync, it will be fixed afterwards.
Li Nan [Sat, 27 May 2023 10:18:51 +0000 (18:18 +0800)]
md/raid10: clean up md_add_new_disk()
Commit 1a855a060665 ("md: fix bug with re-adding of partially recovered
device.") only add device which is set to In_sync. But it let devices
without metadata cannot be added when they should be.
Commit bf572541ab44 ("md: fix regression with re-adding devices to arrays
with no metadata") fix the above issue, it set device without metadata to
In_sync when add new disk.
However, after commit f466722ca614 ("md: Change handling of save_raid_disk
and metadata update during recovery.") deletes changes of the first patch,
setting In_sync for devcie without metadata is meanless because the flag
will be cleared soon and will not be used during this period. Clean it up.
Li Nan [Sat, 27 May 2023 09:20:07 +0000 (17:20 +0800)]
md/raid10: prioritize adding disk to 'removed' mirror
When add a new disk to raid10, it will traverse conf->mirror from start
and find one of the following mirror to add:
1. mirror->rdev is set to WantReplacement and it have no replacement,
set new disk to mirror->replacement.
2. no mirror->rdev, set new disk to mirror->rdev.
There is a array as below (sda is set to WantReplacement):
Number Major Minor RaidDevice State
0 8 0 0 active sync set-A /dev/sda
- 0 0 1 removed
2 8 32 2 active sync set-A /dev/sdc
3 8 48 3 active sync set-B /dev/sdd
Use 'mdadm --add' to add a new disk to this array, the new disk will
become sda's replacement instead of add to removed position, which is
confusing for users. Meanwhile, after new disk recovery success, sda
will be set to Faulty.
Prioritize adding disk to 'removed' mirror is a better choice. In the
above scenario, the behavior is the same as before, except sda will not
be deleted. Before other disks are added, continued use sda is more
reliable.
Li Nan [Sat, 27 May 2023 07:22:16 +0000 (15:22 +0800)]
md/raid10: improve code of mrdev in raid10_sync_request
'need_recover' and 'mrdev' are equivalent in raid10_sync_request(), and
inc mrdev->nr_pending is unreasonable if don't need recovery. Replace
'need_recover' with 'mrdev', and only inc nr_pending when needed.
Li Nan [Sat, 27 May 2023 07:22:15 +0000 (15:22 +0800)]
md/raid10: fix null-ptr-deref of mreplace in raid10_sync_request
There are two check of 'mreplace' in raid10_sync_request(). In the first
check, 'need_replace' will be set and 'mreplace' will be used later if
no-Faulty 'mreplace' exists, In the second check, 'mreplace' will be
set to NULL if it is Faulty, but 'need_replace' will not be changed
accordingly. null-ptr-deref occurs if Faulty is set between two check.
Fix it by merging two checks into one. And replace 'need_replace' with
'mreplace' because their values are always the same.
Yu Kuai [Mon, 29 May 2023 13:34:10 +0000 (21:34 +0800)]
md/raid5: don't start reshape when recovery or replace is in progress
When recovery is interrupted (reboot, etc.) check for MD_RECOVERY_RUNNING
is not enough to tell recovery is in progress. Also check recovery_cp
before starting reshape.
Yu Kuai [Tue, 23 May 2023 02:10:17 +0000 (10:10 +0800)]
md: protect md_thread with rcu
Currently, there are many places that md_thread can be accessed without
protection, following are known scenarios that can cause
null-ptr-dereference or uaf:
1) sync_thread that is allocated and started from md_start_sync()
2) mddev->thread can be accessed directly from timeout_store() and
md_bitmap_daemon_work()
3) md_unregister_thread() from action_store().
Currently, a global spinlock 'pers_lock' is borrowed to protect
'mddev->thread' in some places, this problem can be fixed likewise,
however, use a global lock for all the cases is not good.
Fix this problem by protecting all md_thread with rcu.
Yu Kuai [Tue, 23 May 2023 02:10:16 +0000 (10:10 +0800)]
md/bitmap: factor out a helper to set timeout
Register/unregister 'mddev->thread' are both under 'reconfig_mutex',
however, some context didn't hold the mutex to access mddev->thread,
which can cause null-ptr-deference:
1) md_bitmap_daemon_work() can be called from md_check_recovery() where
'reconfig_mutex' is not held, deference 'mddev->thread' might cause
null-ptr-deference, because md_unregister_thread() reset the pointer
before stopping the thread.
2) timeout_store() access 'mddev->thread' multiple times,
null-ptr-deference can be triggered if 'mddev->thread' is reset in the
middle.
This patch factor out a helper to set timeout, the new helper always
check if 'mddev->thread' is null first, so that problem 1 can be fixed.
Now that this helper only access 'mddev->thread' once, but it's possible
that 'mddev->thread' can be freed while this helper is still in progress,
hence the problem is not fixed yet. Follow up patches will fix this by
protecting md_thread with rcu.
Yu Kuai [Tue, 23 May 2023 02:10:15 +0000 (10:10 +0800)]
md/bitmap: always wake up md_thread in timeout_store
md_wakeup_thread() can handle the case that pass in md_thread is NULL,
the only difference is that md_wakeup_thread() will be called when
current timeout is 'MAX_SCHEDULE_TIMEOUT', this should not matter
because timeout_store() is not hot path, and the daemon process is
woke up more than demand from other context already.
Yu Kuai [Tue, 23 May 2023 02:10:13 +0000 (10:10 +0800)]
md: factor out a helper to wake up md_thread directly
md_wakeup_thread() can't wakeup md_thread->tsk if md_thread->run is
still in progress, and in some cases md_thread->tsk need to be woke up
directly, like md_set_readonly() and do_md_stop().
Commit 9dfbdafda3b3 ("md: unlock mddev before reap sync_thread in
action_store") introduce a new scenario where unregister sync_thread is
not protected by 'reconfig_mutex', this can cause null-ptr-deference in
theroy:
t1: md_set_readonly t2: action_store
md_unregister_thread
// 'reconfig_mutex' is not held
// 'reconfig_mutex' is held by caller
if (mddev->sync_thread)
thread = *threadp
*threadp = NULL
wake_up_process(mddev->sync_thread->tsk)
// null-ptr-deference
Fix this problem by factoring out a helper to wake up md_thread directly,
so that 'sync_thread' won't be accessed multiple times from the reader
side. This helper also prepare to protect md_thread with rcu.
Noted that later patches is going to fix that unregister sync_thread is
not protected by 'reconfig_mutex' from action_store().
Yu Kuai [Tue, 23 May 2023 01:27:27 +0000 (09:27 +0800)]
md: fix duplicate filename for rdev
Commit 5792a2856a63 ("[PATCH] md: avoid a deadlock when removing a device
from an md array via sysfs") delays the deletion of rdev, however, this
introduces a window that rdev can be added again while the deletion is
not done yet, and sysfs will complain about duplicate filename.
Follow up patches try to fix this problem by flushing workqueue, however,
flush_rdev_wq() is just dead code, the progress in
md_kick_rdev_from_array():
So in flush_rdev_wq(), if rdev is found in the list, work_pending() can
never pass, in the meantime, if work is queued, then rdev can never be
found in the list.
flush_rdev_wq() can be replaced by flush_workqueue() directly, however,
this approach is not good:
- the workqueue is global, this synchronization for all raid disks is
not necessary.
- flush_workqueue can't be called under 'reconfig_mutex', there is still
a small window between flush_workqueue() and mddev_lock() that other
contexts can queue new work, hence the problem is not solved completely.
sysfs already has apis to support delete itself through writer, and
these apis, specifically sysfs_break/unbreak_active_protection(), is used
to support deleting rdev synchronously. Therefore, the above commit can be
reverted, and sysfs duplicate filename can be avoided.
A new mdadm regression test is proposed as well([1]).
Li Nan [Mon, 22 May 2023 07:25:33 +0000 (15:25 +0800)]
md/raid10: fix overflow of md/safe_mode_delay
There is no input check when echo md/safe_mode_delay in safe_delay_store().
And msec might also overflow when HZ < 1000 in safe_delay_show(), Fix it by
checking overflow in safe_delay_store() and use unsigned long conversion in
safe_delay_show().
Yu Kuai [Fri, 12 May 2023 01:56:10 +0000 (09:56 +0800)]
md/raid5: fix a deadlock in the case that reshape is interrupted
If reshape is in progress and io across reshape_position is issued, such
io will wait for reshape to make progress(see details in the case that
make_stripe_request() return STRIPE_SCHEDULE_AND_RETRY).
It has been reported several times that if system reboot while growing
raid5 to raid6, array assemble will hang infinitely([1, 2]). This is
because following deadlock is triggered:
1) a normal io is waiting for reshape to progress, this io can be from
system-udevd or mdadm.
2) while assemble, mdadm tries to suspend the array, hence
'reconfig_mutex' is held and mddev_suspend() must wait for normal io
to be done.
3) daemon thread can't start reshape because 'reconfig_mutex' can't be
held.
1) and 3) is unbreakable because they're foundation design. In order to
break 2), following is possible solutions that I can think of:
a) Let mddev_suspend() fail is not a good option, because this will
break many scenarios since mddev_suspend() doesn't fail before.
b) Fail the io that is waiting for reshape to make progress from
mddev_suspend().
c) Return false for the io that is waiting for reshape to make
progress from raid5_make_request(), and these io will wait for
suspend to be done in md_handle_request(), where 'active_io' is
not grabbed.
c) sounds better than b), however, b) is used because it's easy and
straightforward, and it's verified that mdadm can assemble in this case.
On the other hand, c) breaks the logic that mddev_suspend() will wait
for submitted io to be completely handled.
Fix the problem by checking reshape in mddev_suspend(), if reshape can't
make progress and there are still some io waiting for reshape, fail
those io.
Yu Kuai [Fri, 12 May 2023 01:56:06 +0000 (09:56 +0800)]
md/raid5: don't allow replacement while reshape is in progress
If reshape is interrupted(for example, echo frozen to sync_action), then
rdev replacement can be set. It's safe because reshape is always prior to
resync in md_check_recovery(). However, if system reboots, then kernel will
complain cannot handle concurrent replacement and reshape and this array
is not able to assemble anymore.
Fix this problem by don't allow replacement until reshape is done.
Li Nan [Mon, 15 May 2023 13:48:05 +0000 (21:48 +0800)]
md/raid10: check slab-out-of-bounds in md_bitmap_get_counter
If we write a large number to md/bitmap_set_bits, md_bitmap_checkpage()
will return -EINVAL because 'page >= bitmap->pages', but the return value
was not checked immediately in md_bitmap_get_counter() in order to set
*blocks value and slab-out-of-bounds occurs.
Move check of 'page >= bitmap->pages' to md_bitmap_get_counter() and
return directly if true.
Arnd Bergmann [Wed, 17 May 2023 13:22:12 +0000 (15:22 +0200)]
raid6: neon: add missing prototypes
The raid6 syndrome functions are generated for different sizes and have
no generic prototype, while in the inner functions have a prototype
in a header that cannot be included from the correct file. In both
cases, the compiler warns about missing prototypes:
lib/raid6/recov_neon_inner.c:27:6: warning: no previous prototype for '__raid6_2data_recov_neon' [-Wmissing-prototypes]
lib/raid6/recov_neon_inner.c:77:6: warning: no previous prototype for '__raid6_datap_recov_neon' [-Wmissing-prototypes]
lib/raid6/neon1.c:56:6: warning: no previous prototype for 'raid6_neon1_gen_syndrome_real' [-Wmissing-prototypes]
lib/raid6/neon1.c:86:6: warning: no previous prototype for 'raid6_neon1_xor_syndrome_real' [-Wmissing-prototypes]
lib/raid6/neon2.c:56:6: warning: no previous prototype for 'raid6_neon2_gen_syndrome_real' [-Wmissing-prototypes]
lib/raid6/neon2.c:97:6: warning: no previous prototype for 'raid6_neon2_xor_syndrome_real' [-Wmissing-prototypes]
lib/raid6/neon4.c:56:6: warning: no previous prototype for 'raid6_neon4_gen_syndrome_real' [-Wmissing-prototypes]
lib/raid6/neon4.c:119:6: warning: no previous prototype for 'raid6_neon4_xor_syndrome_real' [-Wmissing-prototypes]
lib/raid6/neon8.c:56:6: warning: no previous prototype for 'raid6_neon8_gen_syndrome_real' [-Wmissing-prototypes]
lib/raid6/neon8.c:163:6: warning: no previous prototype for 'raid6_neon8_xor_syndrome_real' [-Wmissing-prototypes]
Add a new header file that contains the prototypes for both to avoid
the warnings.
Yu Kuai [Sat, 10 Jun 2023 02:30:43 +0000 (10:30 +0800)]
blk-mq: fix potential io hang by wrong 'wake_batch'
In __blk_mq_tag_busy/idle(), updating 'active_queues' and calculating
'wake_batch' is not atomic:
t1: t2:
_blk_mq_tag_busy blk_mq_tag_busy
inc active_queues
// assume 1->2
inc active_queues
// 2 -> 3
blk_mq_update_wake_batch
// calculate based on 3
blk_mq_update_wake_batch
/* calculate based on 2, while active_queues is actually 3. */
Fix this problem by protecting them wih 'tags->lock', this is not a hot
path, so performance should not be concerned. And now that all writers
are inside the lock, switch 'actives_queues' from atomic to unsigned
int.
Christoph Hellwig [Thu, 8 Jun 2023 11:02:57 +0000 (13:02 +0200)]
block: store the holder in file->private_data
Store the file struct used as the holder in file->private_data as an
indicator that this file descriptor was opened exclusively to remove
the last use of FMODE_EXCL.
Christoph Hellwig [Thu, 8 Jun 2023 11:02:55 +0000 (13:02 +0200)]
block: replace fmode_t with a block-specific type for block open flags
The only overlap between the block open flags mapped into the fmode_t and
other uses of fmode_t are FMODE_READ and FMODE_WRITE. Define a new
blk_mode_t instead for use in blkdev_get_by_{dev,path}, ->open and
->ioctl and stop abusing fmode_t.
Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd] Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christian Brauner <brauner@kernel.org> Link: https://lore.kernel.org/r/20230608110258.189493-28-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:51 +0000 (13:02 +0200)]
rnbd-srv: replace sess->open_flags with a "bool readonly"
Stop passing the fmode_t around and just use a simple bool to track if
an export is read-only.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Christian Brauner <brauner@kernel.org> Acked-by: Jack Wang <jinpu.wang@ionos.com> Link: https://lore.kernel.org/r/20230608110258.189493-24-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:48 +0000 (13:02 +0200)]
scsi: replace the fmode_t argument to ->sg_io_fn with a simple bool
Instead of passing a fmode_t and only checking it for FMODE_WRITE, pass
a bool open_for_write to prepare for callers that won't have the fmode_t.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Christian Brauner <brauner@kernel.org> Link: https://lore.kernel.org/r/20230608110258.189493-21-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:47 +0000 (13:02 +0200)]
scsi: replace the fmode_t argument to scsi_ioctl with a simple bool
Instead of passing a fmode_t and only checking it for FMODE_WRITE, pass
a bool open_for_write to prepare for callers that won't have the fmode_t.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Christian Brauner <brauner@kernel.org> Link: https://lore.kernel.org/r/20230608110258.189493-20-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:46 +0000 (13:02 +0200)]
scsi: replace the fmode_t argument to scsi_cmd_allowed with a simple bool
Instead of passing a fmode_t and only checking it for FMODE_WRITE, pass
a bool open_for_write to prepare for callers that won't have the fmode_t.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Christian Brauner <brauner@kernel.org> Link: https://lore.kernel.org/r/20230608110258.189493-19-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:43 +0000 (13:02 +0200)]
block: use the holder as indication for exclusive opens
The current interface for exclusive opens is rather confusing as it
requires both the FMODE_EXCL flag and a holder. Remove the need to pass
FMODE_EXCL and just key off the exclusive open off a non-NULL holder.
For blkdev_put this requires adding the holder argument, which provides
better debug checking that only the holder actually releases the hold,
but at the same time allows removing the now superfluous mode argument.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Christian Brauner <brauner@kernel.org> Acked-by: David Sterba <dsterba@suse.com> [btrfs] Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd] Link: https://lore.kernel.org/r/20230608110258.189493-16-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:42 +0000 (13:02 +0200)]
btrfs: don't pass a holder for non-exclusive blkdev_get_by_path
Passing a holder to blkdev_get_by_path when FMODE_EXCL isn't set doesn't
make sense, so pass NULL instead and remove the holder argument from the
call chains the only end up in non-FMODE_EXCL blkdev_get_by_path calls.
Exclusive mode for device scanning is not used since commit 50d281fc434c
("btrfs: scan device in non-exclusive mode")".
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Christian Brauner <brauner@kernel.org> Acked-by: David Sterba <dsterba@suse.com> Link: https://lore.kernel.org/r/20230608110258.189493-15-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:41 +0000 (13:02 +0200)]
rnbd-srv: don't pass a holder for non-exclusive blkdev_get_by_path
Passing a holder to blkdev_get_by_path when FMODE_EXCL isn't set doesn't
make sense, so pass NULL instead.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Christian Brauner <brauner@kernel.org> Acked-by: Jack Wang <jinpu.wang@ionos.com> Link: https://lore.kernel.org/r/20230608110258.189493-14-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:40 +0000 (13:02 +0200)]
bcache: don't pass a stack address to blkdev_get_by_path
sb is just an on-stack pointer that can easily be reused by other calls.
Switch to use the bcache-wide bcache_kobj instead as there is no need to
claim per-bcache device anyway.
Christoph Hellwig [Thu, 8 Jun 2023 11:02:39 +0000 (13:02 +0200)]
swsusp: don't pass a stack address to blkdev_get_by_path
holder is just an on-stack pointer that can easily be reused by other calls,
replace it with a static variable that doesn't change.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Rafael J. Wysocki <rafael@kernel.org> Link: https://lore.kernel.org/r/20230608110258.189493-12-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:37 +0000 (13:02 +0200)]
block: remove the unused mode argument to ->release
The mode argument to the ->release block_device_operation is never used,
so remove it.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Christian Brauner <brauner@kernel.org> Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd] Link: https://lore.kernel.org/r/20230608110258.189493-10-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:36 +0000 (13:02 +0200)]
block: pass a gendisk to ->open
->open is only called on the whole device. Make that explicit by
passing a gendisk instead of the block_device.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Christian Brauner <brauner@kernel.org> Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd] Link: https://lore.kernel.org/r/20230608110258.189493-9-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:35 +0000 (13:02 +0200)]
block: pass a gendisk on bdev_check_media_change
bdev_check_media_change should only ever be called for the whole device.
Pass a gendisk to make that explicit and rename the function to
disk_check_media_change.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Christian Brauner <brauner@kernel.org> Link: https://lore.kernel.org/r/20230608110258.189493-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:33 +0000 (13:02 +0200)]
cdrom: track if a cdrom_device_info was opened for data
Set a flag when a cdrom_device_info is opened for writing, instead of
trying to figure out this at release time. This will allow to eventually
remove the mode argument to the ->release block_device_operation as
nothing but the CDROM drivers uses that argument.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Phillip Potter <phil@philpotter.co.uk> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20230608110258.189493-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Thu, 8 Jun 2023 11:02:29 +0000 (13:02 +0200)]
block: also call ->open for incremental partition opens
For whole devices ->open is called for each open, but for partitions it
is only called on the first open of a partition, e.g.:
open("/dev/vdb", ...)
open("/dev/vdb", ...)
- 2 call to ->open
open("/dev/vdb1", ...)
open("/dev/vdb", ...)
- 2 call to ->open
open("/dev/vdb", ...)
open("/dev/vdb", ...)
- just open call to ->open
This is problematic as various block drivers look at open flags and
might not do all the required setup if the earlier open was with an
odd flag like O_NDELAY or the magic 3 ioctl-only open mode.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Phillip Potter <phil@philpotter.co.uk> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Christian Brauner <brauner@kernel.org> Link: https://lore.kernel.org/r/20230608110258.189493-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Guoqing Jiang [Wed, 24 May 2023 07:00:21 +0000 (15:00 +0800)]
block/rnbd: introduce rnbd_access_modes
Add one new array (marked with __maybe_unused to prevent gcc warning about
"defined but not used" with W=1), then we can remove rnbd_access_mode_str
and rnbd-common.c accordingly.
Andy Shevchenko [Fri, 10 Mar 2023 16:45:44 +0000 (18:45 +0200)]
pktcdvd: Get rid of pkt_seq_show() forward declaration
The code can be neater without forward declarations.
Get rid of pkt_seq_show() forward declaration. This
will also allow futher cleanups to be cleaner.
Andy Shevchenko [Fri, 10 Mar 2023 16:45:43 +0000 (18:45 +0200)]
pktcdvd: use sysfs_emit() to instead of scnprintf()
Follow the advice of the Documentation/filesystems/sysfs.rst and show()
should only use sysfs_emit() or sysfs_emit_at() when formatting the
value to be returned to user space.
Waiman Long [Tue, 6 Jun 2023 18:07:24 +0000 (14:07 -0400)]
blk-cgroup: Reinit blkg_iostat_set after clearing in blkcg_reset_stats()
When blkg_alloc() is called to allocate a blkcg_gq structure
with the associated blkg_iostat_set's, there are 2 fields within
blkg_iostat_set that requires proper initialization - blkg & sync.
The former field was introduced by commit 3b8cc6298724 ("blk-cgroup:
Optimize blkcg_rstat_flush()") while the later one was introduced by
commit f73316482977 ("blk-cgroup: reimplement basic IO stats using
cgroup rstat").
Unfortunately those fields in the blkg_iostat_set's are not properly
re-initialized when they are cleared in v1's blkcg_reset_stats(). This
can lead to a kernel panic due to NULL pointer access of the blkg
pointer. The missing initialization of sync is less problematic and
can be a problem in a debug kernel due to missing lockdep initialization.
Fix these problems by re-initializing them after memory clearing.
Fixes: 3b8cc6298724 ("blk-cgroup: Optimize blkcg_rstat_flush()") Fixes: f73316482977 ("blk-cgroup: reimplement basic IO stats using cgroup rstat") Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20230606180724.2455066-1-longman@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
Yu Kuai [Tue, 6 Jun 2023 01:14:38 +0000 (09:14 +0800)]
blk-ioc: fix recursive spin_lock/unlock_irq() in ioc_clear_queue()
Recursive spin_lock/unlock_irq() is not safe, because spin_unlock_irq()
will enable irq unconditionally:
spin_lock_irq queue_lock -> disable irq
spin_lock_irq ioc->lock
spin_unlock_irq ioc->lock -> enable irq
/*
* AA dead lock will be triggered if current context is preempted by irq,
* and irq try to hold queue_lock again.
*/
spin_unlock_irq queue_lock
Fix this problem by using spin_lock/unlock() directly for 'ioc->lock'.
Zhong Jinghua [Mon, 5 Jun 2023 12:21:59 +0000 (20:21 +0800)]
nbd: Add the maximum limit of allocated index in nbd_dev_add
If the index allocated by idr_alloc greater than MINORMASK >> part_shift,
the device number will overflow, resulting in failure to create a block
device.
Hou Tao [Fri, 28 Apr 2023 07:44:04 +0000 (15:44 +0800)]
blk-ioprio: Introduce promote-to-rt policy
Since commit a78418e6a04c ("block: Always initialize bio IO priority on
submit"), bio->bi_ioprio will never be IOPRIO_CLASS_NONE when calling
blkcg_set_ioprio(), so there will be no way to promote the io-priority
of one cgroup to IOPRIO_CLASS_RT, because bi_ioprio will always be
greater than or equals to IOPRIO_CLASS_RT.
It seems possible to call blkcg_set_ioprio() first then try to
initialize bi_ioprio later in bio_set_ioprio(), but this doesn't work
for bio in which bi_ioprio is already initialized (e.g., direct-io), so
introduce a new promote-to-rt policy to promote the iopriority of bio to
IOPRIO_CLASS_RT if the ioprio is not already RT.
For none-to-rt policy, although it doesn't work now, but considering
that its purpose was also to override the io-priority to RT and allowing
for a smoother transition, just keep it and treat it as an alias of
the promote-to-rt policy.
Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Hou Tao <houtao1@huawei.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Link: https://lore.kernel.org/r/20230428074404.280532-1-houtao@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
Li Nan [Sat, 27 May 2023 09:19:04 +0000 (17:19 +0800)]
blk-iocost: use spin_lock_irqsave in adjust_inuse_and_calc_cost
adjust_inuse_and_calc_cost() use spin_lock_irq() and IRQ will be enabled
when unlock. DEADLOCK might happen if we have held other locks and disabled
IRQ before invoking it.
Fix it by using spin_lock_irqsave() instead, which can keep IRQ state
consistent with before when unlock.
================================
WARNING: inconsistent lock state 5.10.0-02758-g8e5f91fd772f #26 Not tainted
--------------------------------
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
kworker/2:3/388 [HC0[0]:SC0[0]:HE0:SE1] takes: ffff888118c00c28 (&bfqd->lock){?.-.}-{2:2}, at: spin_lock_irq ffff888118c00c28 (&bfqd->lock){?.-.}-{2:2}, at: bfq_bio_merge+0x141/0x390
{IN-HARDIRQ-W} state was registered at:
__lock_acquire+0x3d7/0x1070
lock_acquire+0x197/0x4a0
__raw_spin_lock_irqsave
_raw_spin_lock_irqsave+0x3b/0x60
bfq_idle_slice_timer_body
bfq_idle_slice_timer+0x53/0x1d0
__run_hrtimer+0x477/0xa70
__hrtimer_run_queues+0x1c6/0x2d0
hrtimer_interrupt+0x302/0x9e0
local_apic_timer_interrupt
__sysvec_apic_timer_interrupt+0xfd/0x420
run_sysvec_on_irqstack_cond
sysvec_apic_timer_interrupt+0x46/0xa0
asm_sysvec_apic_timer_interrupt+0x12/0x20
irq event stamp: 837522
hardirqs last enabled at (837521): [<ffffffff84b9419d>] __raw_spin_unlock_irqrestore
hardirqs last enabled at (837521): [<ffffffff84b9419d>] _raw_spin_unlock_irqrestore+0x3d/0x40
hardirqs last disabled at (837522): [<ffffffff84b93fa3>] __raw_spin_lock_irq
hardirqs last disabled at (837522): [<ffffffff84b93fa3>] _raw_spin_lock_irq+0x43/0x50
softirqs last enabled at (835852): [<ffffffff84e00558>] __do_softirq+0x558/0x8ec
softirqs last disabled at (835845): [<ffffffff84c010ff>] asm_call_irq_on_stack+0xf/0x20
other info that might help us debug this:
Possible unsafe locking scenario:
Christoph Hellwig [Wed, 31 May 2023 12:55:34 +0000 (14:55 +0200)]
mtd: block2mtd: don't call early_lookup_bdev after the system is running
early_lookup_bdev is supposed to only be called from the early boot
code, but mdtblock_early_get_bdev is called as a general fallback when
lookup_bdev fails, which is problematic because early_lookup_bdev
bypasses all normal path based permission checking, and might cause
problems with certain container environments renaming devices.
Switch to only call early_lookup_bdev when block2mtd is built-in and the
system state in not running yet.
Note that this strictly speaking changes the kernel ABI as the PARTUUID=
and PARTLABEL= style syntax is now not available during a running
systems. They never were intended for that, but this breaks things
we'll have to figure out a way to make them available again. But if
avoidable in any way I'd rather avoid that.
Christoph Hellwig [Wed, 31 May 2023 12:55:32 +0000 (14:55 +0200)]
PM: hibernate: don't use early_lookup_bdev in resume_store
resume_store is a sysfs attribute written during normal kernel runtime,
and it should not use the early_lookup_bdev API that bypasses all normal
path based permission checking, and might cause problems with certain
container environments renaming devices.
Switch to lookup_bdev, which does a normal path lookup instead, and fall
back to trying to parse a numeric dev_t just like early_lookup_bdev did.
Note that this strictly speaking changes the kernel ABI as the PARTUUID=
and PARTLABEL= style syntax is now not available during a running
systems. They never were intended for that, but this breaks things
we'll have to figure out a way to make them available again. But if
avoidable in any way I'd rather avoid that.
Fixes: 421a5fa1a6cf ("PM / hibernate: use name_to_dev_t to parse resume") Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Rafael J. Wysocki <rafael@kernel.org> Link: https://lore.kernel.org/r/20230531125535.676098-22-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph Hellwig [Wed, 31 May 2023 12:55:31 +0000 (14:55 +0200)]
dm: only call early_lookup_bdev from early boot context
early_lookup_bdev is supposed to only be called from the early boot
code, but dm_get_device calls it as a general fallback when lookup_bdev
fails, which is problematic because early_lookup_bdev bypasses all normal
path based permission checking, and might cause problems with certain
container environments renaming devices.
Switch to only call early_lookup_bdev when dm is built-in and the system
state in not running yet. This means it is still available when tables
are constructed by dm-init.c from the kernel command line, but not
otherwise.
Note that this strictly speaking changes the kernel ABI as the PARTUUID=
and PARTLABEL= style syntax is now not available during a running
systems. They never were intended for that, but this breaks things
we'll have to figure out a way to make them available again. But if
avoidable in any way I'd rather avoid that.
Christoph Hellwig [Wed, 31 May 2023 12:55:25 +0000 (14:55 +0200)]
init: clear root_wait on all invalid root= strings
Instead of only clearing root_wait in devt_from_partuuid when the UUID
format was invalid, do that in parse_root_device for all strings that
failed to parse.
Christoph Hellwig [Wed, 31 May 2023 12:55:24 +0000 (14:55 +0200)]
init: improve the name_to_dev_t interface
name_to_dev_t has a very misleading name, that doesn't make clear
it should only be used by the early init code, and also has a bad
calling convention that doesn't allow returning different kinds of
errors. Rename it to early_lookup_bdev to make the use case clear,
and return an errno, where -EINVAL means the string could not be
parsed, and -ENODEV means it the string was valid, but there was
no device found for it.
Also stub out the whole call for !CONFIG_BLOCK as all the non-block
root cases are always covered in the caller.
Christoph Hellwig [Wed, 31 May 2023 12:55:21 +0000 (14:55 +0200)]
init: handle ubi/mtd root mounting like all other root types
Assign a Root_Generic magic value for UBI/MTD root and handle the root
mounting in mount_root like all other root types. Besides making the
code more clear this also means that UBI/MTD root can be used together
with an initrd (not that anyone should care).
Also factor parsing of the root name into a helper now that it can
be easily done and will get more complicated with subsequent patches.
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