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  1. 09 3月, 2018 12 次提交
  3. 07 3月, 2018 2 次提交
  5. 01 3月, 2018 17 次提交
  7. 28 2月, 2018 4 次提交
    • B
      nvme-multipath: fix sysfs dangerously created links · 9bd82b1a
      由 Baegjae Sung 提交于 
      If multipathing is enabled, each NVMe subsystem creates a head
namespace (e.g., nvme0n1) and multiple private namespaces
(e.g., nvme0c0n1 and nvme0c1n1) in sysfs. When creating links for
private namespaces, links of head namespace are used, so the
namespace creation order must be followed (e.g., nvme0n1 ->
nvme0c1n1). If the order is not followed, links of sysfs will be
incomplete or kernel panic will occur.

The kernel panic was:
  kernel BUG at fs/sysfs/symlink.c:27!
  Call Trace:
    nvme_mpath_add_disk_links+0x5d/0x80 [nvme_core]
    nvme_validate_ns+0x5c2/0x850 [nvme_core]
    nvme_scan_work+0x1af/0x2d0 [nvme_core]

Correct order
Context A     Context B
nvme0n1
nvme0c0n1     nvme0c1n1

Incorrect order
Context A     Context B
              nvme0c1n1
nvme0n1
nvme0c0n1

The nvme_mpath_add_disk (for creating head namespace) is called
just before the nvme_mpath_add_disk_links (for creating private
namespaces). In nvme_mpath_add_disk, the first context acquires
the lock of subsystem and creates a head namespace, and other
contexts do nothing by checking GENHD_FL_UP of a head namespace
after waiting to acquire the lock. We verified the code with or
without multipathing using three vendors of dual-port NVMe SSDs.
Signed-off-by: NBaegjae Sung <baegjae@gmail.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
      9bd82b1a
    • G
      nbd: fix return value in error handling path · 0979962f
      由 Gustavo A. R. Silva 提交于 
      It seems that the proper value to return in this particular case is the
one contained into variable new_index instead of ret.

Addresses-Coverity-ID: 1465148 ("Copy-paste error")
Fixes: e46c7287 ("nbd: add a basic netlink interface")
Reviewed-by: NOmar Sandoval <osandov@fb.com>
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      0979962f
    • T
      bcache: fix kcrashes with fio in RAID5 backend dev · 60eb34ec
      由 Tang Junhui 提交于 
      Kernel crashed when run fio in a RAID5 backend bcache device, the call
trace is bellow:
[  440.012034] kernel BUG at block/blk-ioc.c:146!
[  440.012696] invalid opcode: 0000 [#1] SMP NOPTI
[  440.026537] CPU: 2 PID: 2205 Comm: md127_raid5 Not tainted 4.15.0 #8
[  440.027441] Hardware name: HP ProLiant MicroServer Gen8, BIOS J06 07/16
/2015
[  440.028615] RIP: 0010:put_io_context+0x8b/0x90
[  440.029246] RSP: 0018:ffffa8c882b43af8 EFLAGS: 00010246
[  440.029990] RAX: 0000000000000000 RBX: ffffa8c88294fca0 RCX: 0000000000
0f4240
[  440.031006] RDX: 0000000000000004 RSI: 0000000000000286 RDI: ffffa8c882
94fca0
[  440.032030] RBP: ffffa8c882b43b10 R08: 0000000000000003 R09: ffff949cb8
0c1700
[  440.033206] R10: 0000000000000104 R11: 000000000000b71c R12: 00000000000
01000
[  440.034222] R13: 0000000000000000 R14: ffff949cad84db70 R15: ffff949cb11
bd1e0
[  440.035239] FS:  0000000000000000(0000) GS:ffff949cba280000(0000) knlGS:
0000000000000000
[  440.060190] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  440.084967] CR2: 00007ff0493ef000 CR3: 00000002f1e0a002 CR4: 00000000001
606e0
[  440.110498] Call Trace:
[  440.135443]  bio_disassociate_task+0x1b/0x60
[  440.160355]  bio_free+0x1b/0x60
[  440.184666]  bio_put+0x23/0x30
[  440.208272]  search_free+0x23/0x40 [bcache]
[  440.231448]  cached_dev_write_complete+0x31/0x70 [bcache]
[  440.254468]  closure_put+0xb6/0xd0 [bcache]
[  440.277087]  request_endio+0x30/0x40 [bcache]
[  440.298703]  bio_endio+0xa1/0x120
[  440.319644]  handle_stripe+0x418/0x2270 [raid456]
[  440.340614]  ? load_balance+0x17b/0x9c0
[  440.360506]  handle_active_stripes.isra.58+0x387/0x5a0 [raid456]
[  440.380675]  ? __release_stripe+0x15/0x20 [raid456]
[  440.400132]  raid5d+0x3ed/0x5d0 [raid456]
[  440.419193]  ? schedule+0x36/0x80
[  440.437932]  ? schedule_timeout+0x1d2/0x2f0
[  440.456136]  md_thread+0x122/0x150
[  440.473687]  ? wait_woken+0x80/0x80
[  440.491411]  kthread+0x102/0x140
[  440.508636]  ? find_pers+0x70/0x70
[  440.524927]  ? kthread_associate_blkcg+0xa0/0xa0
[  440.541791]  ret_from_fork+0x35/0x40
[  440.558020] Code: c2 48 00 5b 41 5c 41 5d 5d c3 48 89 c6 4c 89 e7 e8 bb c2
48 00 48 8b 3d bc 36 4b 01 48 89 de e8 7c f7 e0 ff 5b 41 5c 41 5d 5d c3 <0f> 0b
0f 1f 00 0f 1f 44 00 00 55 48 8d 47 b8 48 89 e5 41 57 41
[  440.610020] RIP: put_io_context+0x8b/0x90 RSP: ffffa8c882b43af8
[  440.628575] ---[ end trace a1fd79d85643a73e ]--

All the crash issue happened when a bypass IO coming, in such scenario
s->iop.bio is pointed to the s->orig_bio. In search_free(), it finishes the
s->orig_bio by calling bio_complete(), and after that, s->iop.bio became
invalid, then kernel would crash when calling bio_put(). Maybe its upper
layer's faulty, since bio should not be freed before we calling bio_put(),
but we'd better calling bio_put() first before calling bio_complete() to
notify upper layer ending this bio.

This patch moves bio_complete() under bio_put() to avoid kernel crash.

[mlyle: fixed commit subject for character limits]
Reported-by: NMatthias Ferdinand <bcache@mfedv.net>
Tested-by: NMatthias Ferdinand <bcache@mfedv.net>
Signed-off-by: NTang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: NMichael Lyle <mlyle@lyle.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      60eb34ec
    • C
      bcache: correct flash only vols (check all uuids) · 02aa8a8b
      由 Coly Li 提交于 
      Commit 2831231d ("bcache: reduce cache_set devices iteration by
devices_max_used") adds c->devices_max_used to reduce iteration of
c->uuids elements, this value is updated in bcache_device_attach().

But for flash only volume, when calling flash_devs_run(), the function
bcache_device_attach() is not called yet and c->devices_max_used is not
updated. The unexpected result is, the flash only volume won't be run
by flash_devs_run().

This patch fixes the issue by iterate all c->uuids elements in
flash_devs_run(). c->devices_max_used will be updated properly when
bcache_device_attach() gets called.

[mlyle: commit subject edited for character limit]

Fixes: 2831231d ("bcache: reduce cache_set devices iteration by devices_max_used")
Reported-by: NTang Junhui <tang.junhui@zte.com.cn>
Signed-off-by: NColy Li <colyli@suse.de>
Reviewed-by: NMichael Lyle <mlyle@lyle.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      02aa8a8b
  9. 27 2月, 2018 5 次提交
    • E
      blktrace_api.h: fix comment for struct blk_user_trace_setup · 9c722588
      由 Eric Biggers 提交于 
      'struct blk_user_trace_setup' is passed to BLKTRACESETUP, not
BLKTRACESTART.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      9c722588
    • J
      blockdev: Avoid two active bdev inodes for one device · 560e7cb2
      由 Jan Kara 提交于 
      When blkdev_open() races with device removal and creation it can happen
that unhashed bdev inode gets associated with newly created gendisk
like:

CPU0					CPU1
blkdev_open()
  bdev = bd_acquire()
					del_gendisk()
					  bdev_unhash_inode(bdev);
					remove device
					create new device with the same number
  __blkdev_get()
    disk = get_gendisk()
      - gets reference to gendisk of the new device

Now another blkdev_open() will not find original 'bdev' as it got
unhashed, create a new one and associate it with the same 'disk' at
which point problems start as we have two independent page caches for
one device.

Fix the problem by verifying that the bdev inode didn't get unhashed
before we acquired gendisk reference. That way we make sure gendisk can
get associated only with visible bdev inodes.
Tested-by: NHou Tao <houtao1@huawei.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      560e7cb2
    • J
      genhd: Fix BUG in blkdev_open() · 56c0908c
      由 Jan Kara 提交于 
      When two blkdev_open() calls for a partition race with device removal
and recreation, we can hit BUG_ON(!bd_may_claim(bdev, whole, holder)) in
blkdev_open(). The race can happen as follows:

CPU0				CPU1			CPU2
							del_gendisk()
							  bdev_unhash_inode(part1);

blkdev_open(part1, O_EXCL)	blkdev_open(part1, O_EXCL)
  bdev = bd_acquire()		  bdev = bd_acquire()
  blkdev_get(bdev)
    bd_start_claiming(bdev)
      - finds old inode 'whole'
      bd_prepare_to_claim() -> 0
							  bdev_unhash_inode(whole);
							<device removed>
							<new device under same
							 number created>
				  blkdev_get(bdev);
				    bd_start_claiming(bdev)
				      - finds new inode 'whole'
				      bd_prepare_to_claim()
					- this also succeeds as we have
					  different 'whole' here...
					- bad things happen now as we
					  have two exclusive openers of
					  the same bdev

The problem here is that block device opens can see various intermediate
states while gendisk is shutting down and then being recreated.

We fix the problem by introducing new lookup_sem in gendisk that
synchronizes gendisk deletion with get_gendisk() and furthermore by
making sure that get_gendisk() does not return gendisk that is being (or
has been) deleted. This makes sure that once we ever manage to look up
newly created bdev inode, we are also guaranteed that following
get_gendisk() will either return failure (and we fail open) or it
returns gendisk for the new device and following bdget_disk() will
return new bdev inode (i.e., blkdev_open() follows the path as if it is
completely run after new device is created).
Reported-and-analyzed-by: NHou Tao <houtao1@huawei.com>
Tested-by: NHou Tao <houtao1@huawei.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      56c0908c
    • J
      genhd: Fix use after free in __blkdev_get() · 89736653
      由 Jan Kara 提交于 
      When two blkdev_open() calls race with device removal and recreation,
__blkdev_get() can use looked up gendisk after it is freed:

CPU0				CPU1			CPU2
							del_gendisk(disk);
							  bdev_unhash_inode(inode);
blkdev_open()			blkdev_open()
  bdev = bd_acquire(inode);
    - creates and returns new inode
				  bdev = bd_acquire(inode);
				    - returns the same inode
  __blkdev_get(devt)		  __blkdev_get(devt)
    disk = get_gendisk(devt);
      - got structure of device going away
							<finish device removal>
							<new device gets
							 created under the same
							 device number>
				  disk = get_gendisk(devt);
				    - got new device structure
				  if (!bdev->bd_openers) {
				    does the first open
				  }
    if (!bdev->bd_openers)
      - false
    } else {
      put_disk_and_module(disk)
        - remember this was old device - this was last ref and disk is
          now freed
    }
    disk_unblock_events(disk); -> oops

Fix the problem by making sure we drop reference to disk in
__blkdev_get() only after we are really done with it.
Reported-by: NHou Tao <houtao1@huawei.com>
Tested-by: NHou Tao <houtao1@huawei.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      89736653
    • J
      genhd: Add helper put_disk_and_module() · 9df6c299
      由 Jan Kara 提交于 
      Add a proper counterpart to get_disk_and_module() -
put_disk_and_module(). Currently it is opencoded in several places.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      9df6c299