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2022-05-27block, loop: support partitions without scanningChristoph Hellwig1-0/+2
Historically we did distinguish between a flag that surpressed partition scanning, and a combinations of the minors variable and another flag if any partitions were supported. This was generally confusing and doesn't make much sense, but some corner case uses of the loop driver actually do want to support manually added partitions on a device that does not actively scan for partitions. To make things worsee the loop driver also wants to dynamically toggle the scanning for partitions on a live gendisk, which makes the disk->flags updates non-atomic. Introduce a new GD_SUPPRESS_PART_SCAN bit in disk->state that disables just scanning for partitions, and toggle that instead of GENHD_FL_NO_PART in the loop driver. Fixes: 1ebe2e5f9d68 ("block: remove GENHD_FL_EXT_DEVT") Reported-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220527055806.1972352-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-04-17block: remove queue_discard_alignmentChristoph Hellwig1-1/+1
Just use bdev_alignment_offset in disk_discard_alignment_show instead. That helpers is the same except for an always false branch that doesn't matter in this slow path. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20220415045258.199825-20-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-04-17block: use bdev_alignment_offset in disk_alignment_offset_showChristoph Hellwig1-1/+1
This does the same as the open coded variant except for an extra branch, and allows to remove queue_alignment_offset entirely. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20220415045258.199825-18-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-04-01Merge tag 'for-5.18/block-2022-04-01' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+1
Pull block fixes from Jens Axboe: "Either fixes or a few additions that got missed in the initial merge window pull. In detail: - List iterator fix to avoid leaking value post loop (Jakob) - One-off fix in minor count (Christophe) - Fix for a regression in how io priority setting works for an exiting task (Jiri) - Fix a regression in this merge window with blkg_free() being called in an inappropriate context (Ming) - Misc fixes (Ming, Tom)" * tag 'for-5.18/block-2022-04-01' of git://git.kernel.dk/linux-block: blk-wbt: remove wbt_track stub block: use dedicated list iterator variable block: Fix the maximum minor value is blk_alloc_ext_minor() block: restore the old set_task_ioprio() behaviour wrt PF_EXITING block: avoid calling blkg_free() in atomic context lib/sbitmap: allocate sb->map via kvzalloc_node
2022-03-28block: Fix the maximum minor value is blk_alloc_ext_minor()Christophe JAILLET1-1/+1
ida_alloc_range(..., min, max, ...) returns values from min to max, inclusive. So, NR_EXT_DEVT is a valid idx returned by blk_alloc_ext_minor(). This is an issue because in device_add_disk(), this value is used in: ddev->devt = MKDEV(disk->major, disk->first_minor); and NR_EXT_DEVT is '(1 << MINORBITS)'. So, should 'disk->first_minor' be NR_EXT_DEVT, it would overflow. Fixes: 22ae8ce8b892 ("block: simplify bdev/disk lookup in blkdev_get") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/cc17199798312406b90834e433d2cefe8266823d.1648306232.git.christophe.jaillet@wanadoo.fr Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-24Merge tag 'for-5.18/dm-changes' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - Significant refactoring and fixing of how DM core does bio-based IO accounting with focus on fixing wildly inaccurate IO stats for dm-crypt (and other DM targets that defer bio submission in their own workqueues). End result is proper IO accounting, made possible by targets being updated to use the new dm_submit_bio_remap() interface. - Add hipri bio polling support (REQ_POLLED) to bio-based DM. - Reduce dm_io and dm_target_io structs so that a single dm_io (which contains dm_target_io and first clone bio) weighs in at 256 bytes. For reference the bio struct is 128 bytes. - Various other small cleanups, fixes or improvements in DM core and targets. - Update MAINTAINERS with my kernel.org email address to allow distinction between my "upstream" and "Red" Hats. * tag 'for-5.18/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (46 commits) dm: consolidate spinlocks in dm_io struct dm: reduce size of dm_io and dm_target_io structs dm: switch dm_target_io booleans over to proper flags dm: switch dm_io booleans over to proper flags dm: update email address in MAINTAINERS dm: return void from __send_empty_flush dm: factor out dm_io_complete dm cache: use dm_submit_bio_remap dm: simplify dm_sumbit_bio_remap interface dm thin: use dm_submit_bio_remap dm: add WARN_ON_ONCE to dm_submit_bio_remap dm: support bio polling block: add ->poll_bio to block_device_operations dm mpath: use DMINFO instead of printk with KERN_INFO dm: stop using bdevname dm-zoned: remove the ->name field in struct dmz_dev dm: remove unnecessary local variables in __bind dm: requeue IO if mapping table not yet available dm io: remove stale comment block for dm_io() dm thin metadata: remove unused dm_thin_remove_block and __remove ...
2022-03-21Merge tag 'for-5.18/block-2022-03-18' of git://git.kernel.dk/linux-blockLinus Torvalds1-5/+62
Pull block updates from Jens Axboe: - BFQ cleanups and fixes (Yu, Zhang, Yahu, Paolo) - blk-rq-qos completion fix (Tejun) - blk-cgroup merge fix (Tejun) - Add offline error return value to distinguish it from an IO error on the device (Song) - IO stats fixes (Zhang, Christoph) - blkcg refcount fixes (Ming, Yu) - Fix for indefinite dispatch loop softlockup (Shin'ichiro) - blk-mq hardware queue management improvements (Ming) - sbitmap dead code removal (Ming, John) - Plugging merge improvements (me) - Show blk-crypto capabilities in sysfs (Eric) - Multiple delayed queue run improvement (David) - Block throttling fixes (Ming) - Start deprecating auto module loading based on dev_t (Christoph) - bio allocation improvements (Christoph, Chaitanya) - Get rid of bio_devname (Christoph) - bio clone improvements (Christoph) - Block plugging improvements (Christoph) - Get rid of genhd.h header (Christoph) - Ensure drivers use appropriate flush helpers (Christoph) - Refcounting improvements (Christoph) - Queue initialization and teardown improvements (Ming, Christoph) - Misc fixes/improvements (Barry, Chaitanya, Colin, Dan, Jiapeng, Lukas, Nian, Yang, Eric, Chengming) * tag 'for-5.18/block-2022-03-18' of git://git.kernel.dk/linux-block: (127 commits) block: cancel all throttled bios in del_gendisk() block: let blkcg_gq grab request queue's refcnt block: avoid use-after-free on throttle data block: limit request dispatch loop duration block/bfq-iosched: Fix spelling mistake "tenative" -> "tentative" sr: simplify the local variable initialization in sr_block_open() block: don't merge across cgroup boundaries if blkcg is enabled block: fix rq-qos breakage from skipping rq_qos_done_bio() block: flush plug based on hardware and software queue order block: ensure plug merging checks the correct queue at least once block: move rq_qos_exit() into disk_release() block: do more work in elevator_exit block: move blk_exit_queue into disk_release block: move q_usage_counter release into blk_queue_release block: don't remove hctx debugfs dir from blk_mq_exit_queue block: move blkcg initialization/destroy into disk allocation/release handler sr: implement ->free_disk to simplify refcounting sd: implement ->free_disk to simplify refcounting sd: delay calling free_opal_dev sd: call sd_zbc_release_disk before releasing the scsi_device reference ...
2022-03-18block: cancel all throttled bios in del_gendisk()Yu Kuai1-0/+3
Throttled bios can't be issued after del_gendisk() is done, thus it's better to cancel them immediately rather than waiting for throttle is done. For example, if user thread is throttled with low bps while it's issuing large io, and the device is deleted. The user thread will wait for a long time for io to return. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220318130144.1066064-4-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-09block: add ->poll_bio to block_device_operationsMing Lei1-0/+4
Prepare for supporting IO polling for bio-based driver. Add ->poll_bio callback so that bio-based driver can provide their own logic for polling bio. Also fix ->submit_bio_bio typo in comment block above __submit_bio_noacct. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2022-03-08block: move rq_qos_exit() into disk_release()Ming Lei1-2/+1
Keep all teardown of file system I/O related functionality in one place. There can't be file system I/O in disk_release(), so it is safe to move rq_qos_exit() there. Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220308055200.735835-15-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-08block: do more work in elevator_exitChristoph Hellwig1-3/+0
Move the calls to ioc_clear_queue and blk_mq_sched_free_rqs into elevator_exit. Except for one call where we know we can't have io_cq structures yet these always go together, and that extra call in an error path is harmless. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220308055200.735835-14-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-08block: move blk_exit_queue into disk_releaseMing Lei1-1/+30
There can't be file system I/O in disk_release(), so move the call to blk_exit_queue() there, preparing to have the teardown of file system I/O only functionality in one place, when the gendisk that is needed for it is torn down. We still need to freeze queue here since the request is freed after the bio is completed and passthrough request rely on scheduler tags as well. The disk can be released before or after queue is cleaned up, and we have to free the scheduler request pool before blk_cleanup_queue returns, while the static request pool has to be freed before exiting the I/O scheduler. Signed-off-by: Ming Lei <ming.lei@redhat.com> [hch: rebased, updated the commit log] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20220308055200.735835-13-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-08block: move blkcg initialization/destroy into disk allocation/release handlerMing Lei1-0/+9
blkcg works on FS bio level, so it is reasonable to make both blkcg and gendisk sharing same lifetime. Meantime there won't be any FS IO when releasing disk, so safe to move blkcg initialization/destroy into disk allocation/release handler Long term, we can move blkcg into gendisk completely. Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220308055200.735835-10-hch@lst.de [axboe: fixup missing blk-cgroup.h include] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-22block: update io_ticks when io hangZhang Wensheng1-2/+12
When the inflight IOs are slow and no new IOs are issued, we expect iostat could manifest the IO hang problem. However after commit 5b18b5a73760 ("block: delete part_round_stats and switch to less precise counting"), io_tick and time_in_queue will not be updated until the end of IO, and the avgqu-sz and %util columns of iostat will be zero. Because it has using stat.nsecs accumulation to express time_in_queue which is not suitable to change, and may %util will express the status better when io hang occur. To fix io_ticks, we use update_io_ticks and inflight to update io_ticks when diskstats_show and part_stat_show been called. Fixes: 5b18b5a73760 ("block: delete part_round_stats and switch to less precise counting") Signed-off-by: Zhang Wensheng <zhangwensheng5@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220217064247.4041435-1-zhangwensheng5@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-17block: fix surprise removal for drivers calling blk_set_queue_dyingChristoph Hellwig1-0/+14
Various block drivers call blk_set_queue_dying to mark a disk as dead due to surprise removal events, but since commit 8e141f9eb803 that doesn't work given that the GD_DEAD flag needs to be set to stop I/O. Replace the driver calls to blk_set_queue_dying with a new (and properly documented) blk_mark_disk_dead API, and fold blk_set_queue_dying into the only remaining caller. Fixes: 8e141f9eb803 ("block: drain file system I/O on del_gendisk") Reported-by: Markus Blöchl <markus.bloechl@ipetronik.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Link: https://lore.kernel.org/r/20220217075231.1140-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-16block: add a ->free_disk methodChristoph Hellwig1-0/+5
Add a method to notify the driver that the gendisk is about to be freed. This allows drivers to tie the lifetime of their private data to that of the gendisk and thus deal with device removal races without expensive synchronization and boilerplate code. A new flag is added so that ->free_disk is only called after a successful call to add_disk, which significantly simplifies the error handling path during probing. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220215094514.3828912-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02block: remove genhd.hChristoph Hellwig1-1/+0
There is no good reason to keep genhd.h separate from the main blkdev.h header that includes it. So fold the contents of genhd.h into blkdev.h and remove genhd.h entirely. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20220124093913.742411-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02block: deprecate autoloading based on dev_tChristoph Hellwig1-0/+6
Make the legacy dev_t based autoloading optional and add a deprecation warning. This kind of autoloading has ceased to be useful about 20 years ago. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220104071647.164918-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-12-21block: check minor range in device_add_disk()Tetsuo Handa1-0/+2
ioctl(fd, LOOP_CTL_ADD, 1048576) causes sysfs: cannot create duplicate filename '/dev/block/7:0' message because such request is treated as if ioctl(fd, LOOP_CTL_ADD, 0) due to MINORMASK == 1048575. Verify that all minor numbers for that device fit in the minor range. Reported-by: wangyangbo <wangyangbo@uniontech.com> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/b1b19379-23ee-5379-0eb5-94bf5f79f1b4@i-love.sakura.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-12-21block: fix error unwinding in device_add_diskChristoph Hellwig1-7/+6
One device_add is called disk->ev will be freed by disk_release, so we should free it twice. Fix this by allocating disk->ev after device_add so that the extra local unwinding can be removed entirely. Based on an earlier patch from Tetsuo Handa. Reported-by: syzbot <syzbot+28a66a9fbc621c939000@syzkaller.appspotmail.com> Tested-by: syzbot <syzbot+28a66a9fbc621c939000@syzkaller.appspotmail.com> Fixes: 83cbce9574462c6b ("block: add error handling for device_add_disk / add_disk") Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211221161851.788424-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-12-03blk-mq: move srcu from blk_mq_hw_ctx to request_queueMing Lei1-1/+1
In case of BLK_MQ_F_BLOCKING, per-hctx srcu is used to protect dispatch critical area. However, this srcu instance stays at the end of hctx, and it often takes standalone cacheline, often cold. Inside srcu_read_lock() and srcu_read_unlock(), WRITE is always done on the indirect percpu variable which is allocated from heap instead of being embedded, srcu->srcu_idx is read only in srcu_read_lock(). It doesn't matter if srcu structure stays in hctx or request queue. So switch to per-request-queue srcu for protecting dispatch, and this way simplifies quiesce a lot, not mention quiesce is always done on the request queue wide. Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20211203131534.3668411-3-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: don't include <linux/part_stat.h> in blk.hChristoph Hellwig1-0/+1
Not needed, shift it into the source files that need it instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211123185312.1432157-9-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: don't include blk-mq-sched.h in blk.hChristoph Hellwig1-0/+1
No needed, shift it into the source files that need it instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211123185312.1432157-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: don't set GENHD_FL_NO_PART for hidden gendisksChristoph Hellwig1-7/+2
Hidden gendisks can't be opened using blkdev_get_*, so we can't really reach any of the partition scanning paths or partitioning ioctls except for the initial partition scan from add_disk. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211122130625.1136848-13-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: remove GENHD_FL_EXT_DEVTChristoph Hellwig1-3/+3
All modern drivers can support extra partitions using the extended dev_t. In fact except for the ioctl method drivers never even see partitions in normal operation. So remove the GENHD_FL_EXT_DEVT and allow extra partitions for all block devices that do support partitions, and require those that do not support partitions to explicit disallow them using GENHD_FL_NO_PART. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211122130625.1136848-12-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: remove GENHD_FL_SUPPRESS_PARTITION_INFOChristoph Hellwig1-8/+3
This flag is not set directly anywhere and only inherited from GENHD_FL_HIDDEN. Just check for GENHD_FL_HIDDEN instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211122130625.1136848-11-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: rename GENHD_FL_NO_PART_SCAN to GENHD_FL_NO_PARTChristoph Hellwig1-1/+1
The GENHD_FL_NO_PART_SCAN controls more than just partitions canning, so rename it to GENHD_FL_NO_PART. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://lore.kernel.org/r/20211122130625.1136848-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: merge disk_scan_partitions and blkdev_reread_partChristoph Hellwig1-7/+12
Unify the functionality that implements a partition rescan for a gendisk. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211122130625.1136848-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: remove a dead check in show_partitionChristoph Hellwig1-3/+1
disk_max_parts never returns 0 given that ->minors for devices not using the extended dev_t must be non-zero, and disk_max_parts always returns DISK_MAX_PARTS for the latter. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211122130625.1136848-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-15blk-mq: cancel blk-mq dispatch work in both blk_cleanup_queue and disk_release()Ming Lei1-0/+2
For avoiding to slow down queue destroy, we don't call blk_mq_quiesce_queue() in blk_cleanup_queue(), instead of delaying to cancel dispatch work in blk_release_queue(). However, this way has caused kernel oops[1], reported by Changhui. The log shows that scsi_device can be freed before running blk_release_queue(), which is expected too since scsi_device is released after the scsi disk is closed and the scsi_device is removed. Fixes the issue by canceling blk-mq dispatch work in both blk_cleanup_queue() and disk_release(): 1) when disk_release() is run, the disk has been closed, and any sync dispatch activities have been done, so canceling dispatch work is enough to quiesce filesystem I/O dispatch activity. 2) in blk_cleanup_queue(), we only focus on passthrough request, and passthrough request is always explicitly allocated & freed by its caller, so once queue is frozen, all sync dispatch activity for passthrough request has been done, then it is enough to just cancel dispatch work for avoiding any dispatch activity. [1] kernel panic log [12622.769416] BUG: kernel NULL pointer dereference, address: 0000000000000300 [12622.777186] #PF: supervisor read access in kernel mode [12622.782918] #PF: error_code(0x0000) - not-present page [12622.788649] PGD 0 P4D 0 [12622.791474] Oops: 0000 [#1] PREEMPT SMP PTI [12622.796138] CPU: 10 PID: 744 Comm: kworker/10:1H Kdump: loaded Not tainted 5.15.0+ #1 [12622.804877] Hardware name: Dell Inc. PowerEdge R730/0H21J3, BIOS 1.5.4 10/002/2015 [12622.813321] Workqueue: kblockd blk_mq_run_work_fn [12622.818572] RIP: 0010:sbitmap_get+0x75/0x190 [12622.823336] Code: 85 80 00 00 00 41 8b 57 08 85 d2 0f 84 b1 00 00 00 45 31 e4 48 63 cd 48 8d 1c 49 48 c1 e3 06 49 03 5f 10 4c 8d 6b 40 83 f0 01 <48> 8b 33 44 89 f2 4c 89 ef 0f b6 c8 e8 fa f3 ff ff 83 f8 ff 75 58 [12622.844290] RSP: 0018:ffffb00a446dbd40 EFLAGS: 00010202 [12622.850120] RAX: 0000000000000001 RBX: 0000000000000300 RCX: 0000000000000004 [12622.858082] RDX: 0000000000000006 RSI: 0000000000000082 RDI: ffffa0b7a2dfe030 [12622.866042] RBP: 0000000000000004 R08: 0000000000000001 R09: ffffa0b742721334 [12622.874003] R10: 0000000000000008 R11: 0000000000000008 R12: 0000000000000000 [12622.881964] R13: 0000000000000340 R14: 0000000000000000 R15: ffffa0b7a2dfe030 [12622.889926] FS: 0000000000000000(0000) GS:ffffa0baafb40000(0000) knlGS:0000000000000000 [12622.898956] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [12622.905367] CR2: 0000000000000300 CR3: 0000000641210001 CR4: 00000000001706e0 [12622.913328] Call Trace: [12622.916055] <TASK> [12622.918394] scsi_mq_get_budget+0x1a/0x110 [12622.922969] __blk_mq_do_dispatch_sched+0x1d4/0x320 [12622.928404] ? pick_next_task_fair+0x39/0x390 [12622.933268] __blk_mq_sched_dispatch_requests+0xf4/0x140 [12622.939194] blk_mq_sched_dispatch_requests+0x30/0x60 [12622.944829] __blk_mq_run_hw_queue+0x30/0xa0 [12622.949593] process_one_work+0x1e8/0x3c0 [12622.954059] worker_thread+0x50/0x3b0 [12622.958144] ? rescuer_thread+0x370/0x370 [12622.962616] kthread+0x158/0x180 [12622.966218] ? set_kthread_struct+0x40/0x40 [12622.970884] ret_from_fork+0x22/0x30 [12622.974875] </TASK> [12622.977309] Modules linked in: scsi_debug rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs sunrpc dm_multipath intel_rapl_msr intel_rapl_common dell_wmi_descriptor sb_edac rfkill video x86_pkg_temp_thermal intel_powerclamp dcdbas coretemp kvm_intel kvm mgag200 irqbypass i2c_algo_bit rapl drm_kms_helper ipmi_ssif intel_cstate intel_uncore syscopyarea sysfillrect sysimgblt fb_sys_fops pcspkr cec mei_me lpc_ich mei ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter drm fuse xfs libcrc32c sr_mod cdrom sd_mod t10_pi sg ixgbe ahci libahci crct10dif_pclmul crc32_pclmul crc32c_intel libata megaraid_sas ghash_clmulni_intel tg3 wdat_wdt mdio dca wmi dm_mirror dm_region_hash dm_log dm_mod [last unloaded: scsi_debug] Reported-by: ChanghuiZhong <czhong@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Bart Van Assche <bvanassche@acm.org> Cc: linux-scsi@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20211116014343.610501-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-09block: add __must_check for *add_disk*() callersLuis Chamberlain1-3/+3
Now that we have done a spring cleaning on all drivers and added error checking / handling, let's keep it that way and ensure no new drivers fail to stick with it. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20211110002949.999380-1-mcgrof@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-09Merge tag 'for-5.16/drivers-2021-11-09' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+4
Pull more block driver updates from Jens Axboe: - Last series adding error handling support for add_disk() in drivers. After this one, and once the SCSI side has been merged, we can finally annotate add_disk() as must_check. (Luis) - bcache fixes (Coly) - zram fixes (Ming) - ataflop locking fix (Tetsuo) - nbd fixes (Ye, Yu) - MD merge via Song - Cleanup (Yang) - sysfs fix (Guoqing) - Misc fixes (Geert, Wu, luo) * tag 'for-5.16/drivers-2021-11-09' of git://git.kernel.dk/linux-block: (34 commits) bcache: Revert "bcache: use bvec_virt" ataflop: Add missing semicolon to return statement floppy: address add_disk() error handling on probe ataflop: address add_disk() error handling on probe block: update __register_blkdev() probe documentation ataflop: remove ataflop_probe_lock mutex mtd/ubi/block: add error handling support for add_disk() block/sunvdc: add error handling support for add_disk() z2ram: add error handling support for add_disk() nvdimm/pmem: use add_disk() error handling nvdimm/pmem: cleanup the disk if pmem_release_disk() is yet assigned nvdimm/blk: add error handling support for add_disk() nvdimm/blk: avoid calling del_gendisk() on early failures nvdimm/btt: add error handling support for add_disk() nvdimm/btt: use goto error labels on btt_blk_init() loop: Remove duplicate assignments drbd: Fix double free problem in drbd_create_device nvdimm/btt: do not call del_gendisk() if not needed bcache: fix use-after-free problem in bcache_device_free() zram: replace fsync_bdev with sync_blockdev ...
2021-11-09Merge tag 'for-5.16/block-2021-11-09' of git://git.kernel.dk/linux-blockLinus Torvalds1-2/+6
Pull block fixes from Jens Axboe: - Set of fixes for the batched tag allocation (Ming, me) - add_disk() error handling fix (Luis) - Nested queue quiesce fixes (Ming) - Shared tags init error handling fix (Ye) - Misc cleanups (Jean, Ming, me) * tag 'for-5.16/block-2021-11-09' of git://git.kernel.dk/linux-block: nvme: wait until quiesce is done scsi: make sure that request queue queiesce and unquiesce balanced scsi: avoid to quiesce sdev->request_queue two times blk-mq: add one API for waiting until quiesce is done blk-mq: don't free tags if the tag_set is used by other device in queue initialztion block: fix device_add_disk() kobject_create_and_add() error handling block: ensure cached plug request matches the current queue block: move queue enter logic into blk_mq_submit_bio() block: make bio_queue_enter() fast-path available inline block: split request allocation components into helpers block: have plug stored requests hold references to the queue blk-mq: update hctx->nr_active in blk_mq_end_request_batch() blk-mq: add RQF_ELV debug entry blk-mq: only try to run plug merge if request has same queue with incoming bio block: move RQF_ELV setting into allocators dm: don't stop request queue after the dm device is suspended block: replace always false argument with 'false' block: assign correct tag before doing prefetch of request blk-mq: fix redundant check of !e expression
2021-11-04block: fix device_add_disk() kobject_create_and_add() error handlingLuis Chamberlain1-2/+6
Commit 83cbce957446 ("block: add error handling for device_add_disk / add_disk") added error handling to device_add_disk(), however the goto label for the kobject_create_and_add() failure did not set the return value correctly, and so we can end up in a situation where kobject_create_and_add() fails but we report success. Fixes: 83cbce957446 ("block: add error handling for device_add_disk / add_disk") Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211103164023.1384821-1-mcgrof@kernel.org [axboe: fold in followup fix from Wu Bo <wubo40@huawei.com>] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-04block: update __register_blkdev() probe documentationLuis Chamberlain1-1/+4
__register_blkdev() is used to register a probe callback, and that callback is typically used to call add_disk(). Now that we are able to capture errors for add_disk(), we need to fix those probe calls where add_disk() fails and clean up resources. We don't extend the probe call to return the error given: 1) we'd have to always special-case the case where the disk was already present, as otherwise concurrent requests to open an existing block device would fail, and this would be a userspace visible change 2) the error from ilookup() on blkdev_get_no_open() is sufficient 3) The only thing the probe call is used for is to support pre-devtmpfs, pre-udev semantics that want to create disks when their pre-created device node is accessed, and so we don't care for failures on probe there. Expand documentation for the probe callback to ensure users cleanup resources if add_disk() is used and to clarify this interface may be removed in the future. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20211103230437.1639990-12-mcgrof@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-01Merge tag 'for-5.16/bdev-size-2021-10-29' of git://git.kernel.dk/linux-blockLinus Torvalds1-0/+1
Pull bdev size cleanups from Jens Axboe: "Clean up the bdev size handling with new bdev_nr_bytes() helper" * tag 'for-5.16/bdev-size-2021-10-29' of git://git.kernel.dk/linux-block: (34 commits) partitions/ibm: use bdev_nr_sectors instead of open coding it partitions/efi: use bdev_nr_bytes instead of open coding it block/ioctl: use bdev_nr_sectors and bdev_nr_bytes block: cache inode size in bdev udf: use sb_bdev_nr_blocks reiserfs: use sb_bdev_nr_blocks ntfs: use sb_bdev_nr_blocks jfs: use sb_bdev_nr_blocks ext4: use sb_bdev_nr_blocks block: add a sb_bdev_nr_blocks helper block: use bdev_nr_bytes instead of open coding it in blkdev_fallocate squashfs: use bdev_nr_bytes instead of open coding it reiserfs: use bdev_nr_bytes instead of open coding it pstore/blk: use bdev_nr_bytes instead of open coding it ntfs3: use bdev_nr_bytes instead of open coding it nilfs2: use bdev_nr_bytes instead of open coding it nfs/blocklayout: use bdev_nr_bytes instead of open coding it jfs: use bdev_nr_bytes instead of open coding it hfsplus: use bdev_nr_sectors instead of open coding it hfs: use bdev_nr_sectors instead of open coding it ...
2021-11-01Merge tag 'for-5.16/block-2021-10-29' of git://git.kernel.dk/linux-blockLinus Torvalds1-9/+26
Pull block updates from Jens Axboe: - mq-deadline accounting improvements (Bart) - blk-wbt timer fix (Andrea) - Untangle the block layer includes (Christoph) - Rework the poll support to be bio based, which will enable adding support for polling for bio based drivers (Christoph) - Block layer core support for multi-actuator drives (Damien) - blk-crypto improvements (Eric) - Batched tag allocation support (me) - Request completion batching support (me) - Plugging improvements (me) - Shared tag set improvements (John) - Concurrent queue quiesce support (Ming) - Cache bdev in ->private_data for block devices (Pavel) - bdev dio improvements (Pavel) - Block device invalidation and block size improvements (Xie) - Various cleanups, fixes, and improvements (Christoph, Jackie, Masahira, Tejun, Yu, Pavel, Zheng, me) * tag 'for-5.16/block-2021-10-29' of git://git.kernel.dk/linux-block: (174 commits) blk-mq-debugfs: Show active requests per queue for shared tags block: improve readability of blk_mq_end_request_batch() virtio-blk: Use blk_validate_block_size() to validate block size loop: Use blk_validate_block_size() to validate block size nbd: Use blk_validate_block_size() to validate block size block: Add a helper to validate the block size block: re-flow blk_mq_rq_ctx_init() block: prefetch request to be initialized block: pass in blk_mq_tags to blk_mq_rq_ctx_init() block: add rq_flags to struct blk_mq_alloc_data block: add async version of bio_set_polled block: kill DIO_MULTI_BIO block: kill unused polling bits in __blkdev_direct_IO() block: avoid extra iter advance with async iocb block: Add independent access ranges support blk-mq: don't issue request directly in case that current is to be blocked sbitmap: silence data race warning blk-cgroup: synchronize blkg creation against policy deactivation block: refactor bio_iov_bvec_set() block: add single bio async direct IO helper ...
2021-10-26block: drain queue after disk is removed from sysfsMing Lei1-10/+12
Before removing disk from sysfs, userspace still may change queue via sysfs, such as switching elevator or setting wbt latency, both may reinitialize wbt, then the warning in blk_free_queue_stats() will be triggered since rq_qos_exit() is moved to del_gendisk(). Fixes the issue by moving draining queue & tearing down after disk is removed from sysfs, at that time no one can come into queue's store()/show(). Reported-by: Yi Zhang <yi.zhang@redhat.com> Tested-by: Yi Zhang <yi.zhang@redhat.com> Fixes: 8e141f9eb803 ("block: drain file system I/O on del_gendisk") Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20211026101204.2897166-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-21block: Add invalidate_disk() helper to invalidate the gendiskXie Yongji1-0/+20
To hide internal implementation and simplify some driver code, this adds a helper to invalidate the gendisk. It will clean the gendisk's associated buffer/page caches and reset its internal states. Signed-off-by: Xie Yongji <xieyongji@bytedance.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210922123711.187-2-xieyongji@bytedance.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19block: move bdev_read_only() into the headerJens Axboe1-6/+0
This is called for every write in the fast path, move it inline next to get_disk_ro() which is called internally. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18block: cache inode size in bdevJens Axboe1-0/+1
Reading the inode size brings in a new cacheline for IO submit, and it's in the hot path being checked for every single IO. When doing millions of IOs per core per second, this is noticeable overhead. Cache the nr_sectors in the bdev itself. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18block: convert the rest of block to bdev_get_queuePavel Begunkov1-2/+2
Convert bdev->bd_disk->queue to bdev_get_queue(), it's uses a cached queue pointer and so is faster. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/addf6ea988c04213697ba3684c853e4ed7642a39.1634219547.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18block: cache request queue in bdevPavel Begunkov1-1/+3
There are tons of places where we need to get a request_queue only having bdev, which turns into bdev->bd_disk->queue. There are probably a hundred of such places considering inline helpers, and enough of them are in hot paths. Cache queue pointer in struct block_device and make use of it in bdev_get_queue(). Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/a3bfaecdd28956f03629d0ca5c63ebc096e1c809.1634219547.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18block: drop unused includes in <linux/genhd.h>Christoph Hellwig1-0/+1
Drop various include not actually used in genhd.h itself, and move the remaning includes closer together. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210920123328.1399408-15-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-17block: warn when putting the final reference on a registered diskChristoph Hellwig1-0/+1
Warn when the last reference on a live disk is put without calling del_gendisk first. There are some BDI related bug reports that look like a case of this, so make sure we have the proper instrumentation to catch it. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211014130231.1468538-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-15block: keep q_usage_counter in atomic mode after del_gendiskChristoph Hellwig1-1/+2
Don't switch back to percpu mode to avoid the double RCU grace period when tearing down SCSI devices. After removing the disk only passthrough commands can be send anyway. Suggested-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Darrick J. Wong <djwong@kernel.org> Link: https://lore.kernel.org/r/20210929071241.934472-6-hch@lst.de Tested-by: Yi Zhang <yi.zhang@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-15block: drain file system I/O on del_gendiskChristoph Hellwig1-0/+21
Instead of delaying draining of file system I/O related items like the blk-qos queues, the integrity read workqueue and timeouts only when the request_queue is removed, do that when del_gendisk is called. This is important for SCSI where the upper level drivers that control the gendisk are separate entities, and the disk can be freed much earlier than the request_queue, or can even be unbound without tearing down the queue. Fixes: edb0872f44ec ("block: move the bdi from the request_queue to the gendisk") Reported-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Darrick J. Wong <djwong@kernel.org> Link: https://lore.kernel.org/r/20210929071241.934472-5-hch@lst.de Tested-by: Yi Zhang <yi.zhang@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-02block: genhd: fix double kfree() in __alloc_disk_node()Tetsuo Handa1-0/+1
syzbot is reporting use-after-free read at bdev_free_inode() [1], for kfree() from __alloc_disk_node() is called before bdev_free_inode() (which is called after RCU grace period) reads bdev->bd_disk and calls kfree(bdev->bd_disk). Fix use-after-free read followed by double kfree() problem by making sure that bdev->bd_disk is NULL when calling iput(). Link: https://syzkaller.appspot.com/bug?extid=8281086e8a6fbfbd952a [1] Reported-by: syzbot <syzbot+8281086e8a6fbfbd952a@syzkaller.appspotmail.com> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/e6dd13c5-8db0-4392-6e78-a42ee5d2a1c4@i-love.sakura.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-09-07block: genhd: don't call blkdev_show() with major_names_lock heldTetsuo Handa1-2/+7
If CONFIG_BLK_DEV_LOOP && CONFIG_MTD (at least; there might be other combinations), lockdep complains circular locking dependency at __loop_clr_fd(), for major_names_lock serves as a locking dependency aggregating hub across multiple block modules. ====================================================== WARNING: possible circular locking dependency detected 5.14.0+ #757 Tainted: G E ------------------------------------------------------ systemd-udevd/7568 is trying to acquire lock: ffff88800f334d48 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x70/0x560 but task is already holding lock: ffff888014a7d4a0 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x4d/0x400 [loop] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&lo->lo_mutex){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_killable_nested+0x17/0x20 lo_open+0x23/0x50 [loop] blkdev_get_by_dev+0x199/0x540 blkdev_open+0x58/0x90 do_dentry_open+0x144/0x3a0 path_openat+0xa57/0xda0 do_filp_open+0x9f/0x140 do_sys_openat2+0x71/0x150 __x64_sys_openat+0x78/0xa0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #5 (&disk->open_mutex){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_nested+0x17/0x20 bd_register_pending_holders+0x20/0x100 device_add_disk+0x1ae/0x390 loop_add+0x29c/0x2d0 [loop] blk_request_module+0x5a/0xb0 blkdev_get_no_open+0x27/0xa0 blkdev_get_by_dev+0x5f/0x540 blkdev_open+0x58/0x90 do_dentry_open+0x144/0x3a0 path_openat+0xa57/0xda0 do_filp_open+0x9f/0x140 do_sys_openat2+0x71/0x150 __x64_sys_openat+0x78/0xa0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #4 (major_names_lock){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_nested+0x17/0x20 blkdev_show+0x19/0x80 devinfo_show+0x52/0x60 seq_read_iter+0x2d5/0x3e0 proc_reg_read_iter+0x41/0x80 vfs_read+0x2ac/0x330 ksys_read+0x6b/0xd0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #3 (&p->lock){+.+.}-{3:3}: lock_acquire+0xbe/0x1f0 __mutex_lock_common+0xb6/0xe10 mutex_lock_nested+0x17/0x20 seq_read_iter+0x37/0x3e0 generic_file_splice_read+0xf3/0x170 splice_direct_to_actor+0x14e/0x350 do_splice_direct+0x84/0xd0 do_sendfile+0x263/0x430 __se_sys_sendfile64+0x96/0xc0 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (sb_writers#3){.+.+}-{0:0}: lock_acquire+0xbe/0x1f0 lo_write_bvec+0x96/0x280 [loop] loop_process_work+0xa68/0xc10 [loop] process_one_work+0x293/0x480 worker_thread+0x23d/0x4b0 kthread+0x163/0x180 ret_from_fork+0x1f/0x30 -> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}: lock_acquire+0xbe/0x1f0 process_one_work+0x280/0x480 worker_thread+0x23d/0x4b0 kthread+0x163/0x180 ret_from_fork+0x1f/0x30 -> #0 ((wq_completion)loop0){+.+.}-{0:0}: validate_chain+0x1f0d/0x33e0 __lock_acquire+0x92d/0x1030 lock_acquire+0xbe/0x1f0 flush_workqueue+0x8c/0x560 drain_workqueue+0x80/0x140 destroy_workqueue+0x47/0x4f0 __loop_clr_fd+0xb4/0x400 [loop] blkdev_put+0x14a/0x1d0 blkdev_close+0x1c/0x20 __fput+0xfd/0x220 task_work_run+0x69/0xc0 exit_to_user_mode_prepare+0x1ce/0x1f0 syscall_exit_to_user_mode+0x26/0x60 do_syscall_64+0x4c/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: (wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&lo->lo_mutex); lock(&disk->open_mutex); lock(&lo->lo_mutex); lock((wq_completion)loop0); *** DEADLOCK *** 2 locks held by systemd-udevd/7568: #0: ffff888012554128 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x4c/0x1d0 #1: ffff888014a7d4a0 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x4d/0x400 [loop] stack backtrace: CPU: 0 PID: 7568 Comm: systemd-udevd Tainted: G E 5.14.0+ #757 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 02/27/2020 Call Trace: dump_stack_lvl+0x79/0xbf print_circular_bug+0x5d6/0x5e0 ? stack_trace_save+0x42/0x60 ? save_trace+0x3d/0x2d0 check_noncircular+0x10b/0x120 validate_chain+0x1f0d/0x33e0 ? __lock_acquire+0x953/0x1030 ? __lock_acquire+0x953/0x1030 __lock_acquire+0x92d/0x1030 ? flush_workqueue+0x70/0x560 lock_acquire+0xbe/0x1f0 ? flush_workqueue+0x70/0x560 flush_workqueue+0x8c/0x560 ? flush_workqueue+0x70/0x560 ? sched_clock_cpu+0xe/0x1a0 ? drain_workqueue+0x41/0x140 drain_workqueue+0x80/0x140 destroy_workqueue+0x47/0x4f0 ? blk_mq_freeze_queue_wait+0xac/0xd0 __loop_clr_fd+0xb4/0x400 [loop] ? __mutex_unlock_slowpath+0x35/0x230 blkdev_put+0x14a/0x1d0 blkdev_close+0x1c/0x20 __fput+0xfd/0x220 task_work_run+0x69/0xc0 exit_to_user_mode_prepare+0x1ce/0x1f0 syscall_exit_to_user_mode+0x26/0x60 do_syscall_64+0x4c/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f0fd4c661f7 Code: 00 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 13 fc ff ff RSP: 002b:00007ffd1c9e9fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 00007f0fd46be6c8 RCX: 00007f0fd4c661f7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 0000000000000006 R08: 000055fff1eaf400 R09: 0000000000000000 R10: 00007f0fd46be6c8 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000002f08 R15: 00007ffd1c9ea050 Commit 1c500ad706383f1a ("loop: reduce the loop_ctl_mutex scope") is for breaking "loop_ctl_mutex => &lo->lo_mutex" dependency chain. But enabling a different block module results in forming circular locking dependency due to shared major_names_lock mutex. The simplest fix is to call probe function without holding major_names_lock [1], but Christoph Hellwig does not like such idea. Therefore, instead of holding major_names_lock in blkdev_show(), introduce a different lock for blkdev_show() in order to break "sb_writers#$N => &p->lock => major_names_lock" dependency chain. Link: https://lkml.kernel.org/r/b2af8a5b-3c1b-204e-7f56-bea0b15848d6@i-love.sakura.ne.jp [1] Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Link: https://lore.kernel.org/r/18a02da2-0bf3-550e-b071-2b4ab13c49f0@i-love.sakura.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-24block: refine the disk_live check in del_gendiskChristoph Hellwig1-1/+1
hidden gendisks will never be marked live. Fixes: 40b3a52ffc5b ("block: add a sanity check for a live disk in del_gendisk") Reported-by: Bruno Goncalves <bgoncalv@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210824144310.1487816-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-03 05:50:53 +0000