linux-toradex.git/drivers/md, branch v5.1-rc4

dm integrity: fix deadlock with overlapping I/O

2019-04-05T22:49:08+00:00

dm-integrity will deadlock if overlapping I/O is issued to it, the bug
was introduced by commit 724376a04d1a ("dm integrity: implement fair
range locks").  Users rarely use overlapping I/O so this bug went
undetected until now.

Fix this bug by correcting, likely cut-n-paste, typos in
ranges_overlap() and also remove a flawed ranges_overlap() check in
remove_range_unlocked().  This condition could leave unprocessed bios
hanging on wait_list forever.

Cc: stable@vger.kernel.org # v4.19+
Fixes: 724376a04d1a ("dm integrity: implement fair range locks")
Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

dm: disable DISCARD if the underlying storage no longer supports it

2019-04-04T19:33:59+00:00

Storage devices which report supporting discard commands like
WRITE_SAME_16 with unmap, but reject discard commands sent to the
storage device.  This is a clear storage firmware bug but it doesn't
change the fact that should a program cause discards to be sent to a
multipath device layered on this buggy storage, all paths can end up
failed at the same time from the discards, causing possible I/O loss.

The first discard to a path will fail with Illegal Request, Invalid
field in cdb, e.g.:
 kernel: sd 8:0:8:19: [sdfn] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
 kernel: sd 8:0:8:19: [sdfn] tag#0 Sense Key : Illegal Request [current]
 kernel: sd 8:0:8:19: [sdfn] tag#0 Add. Sense: Invalid field in cdb
 kernel: sd 8:0:8:19: [sdfn] tag#0 CDB: Write same(16) 93 08 00 00 00 00 00 a0 08 00 00 00 80 00 00 00
 kernel: blk_update_request: critical target error, dev sdfn, sector 10487808

The SCSI layer converts this to the BLK_STS_TARGET error number, the sd
device disables its support for discard on this path, and because of the
BLK_STS_TARGET error multipath fails the discard without failing any
path or retrying down a different path.  But subsequent discards can
cause path failures.  Any discards sent to the path which already failed
a discard ends up failing with EIO from blk_cloned_rq_check_limits with
an "over max size limit" error since the discard limit was set to 0 by
the sd driver for the path.  As the error is EIO, this now fails the
path and multipath tries to send the discard down the next path.  This
cycle continues as discards are sent until all paths fail.

Fix this by training DM core to disable DISCARD if the underlying
storage already did so.

Also, fix branching in dm_done() and clone_endio() to reflect the
mutually exclussive nature of the IO operations in question.

Cc: stable@vger.kernel.org
Reported-by: David Jeffery 
Signed-off-by: Mike Snitzer

dm table: propagate BDI_CAP_STABLE_WRITES to fix sporadic checksum errors

2019-04-01T20:26:02+00:00

Some devices don't use blk_integrity but still want stable pages
because they do their own checksumming.  Examples include rbd and iSCSI
when data digests are negotiated.  Stacking DM (and thus LVM) on top of
these devices results in sporadic checksum errors.

Set BDI_CAP_STABLE_WRITES if any underlying device has it set.

Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov 
Signed-off-by: Mike Snitzer

dm: revert 8f50e358153d ("dm: limit the max bio size as BIO_MAX_PAGES * PAGE_SIZE")

2019-04-01T20:20:36+00:00

The limit was already incorporated to dm-crypt with commit 4e870e948fba
("dm crypt: fix error with too large bios"), so we don't need to apply
it globally to all targets. The quantity BIO_MAX_PAGES * PAGE_SIZE is
wrong anyway because the variable ti->max_io_len it is supposed to be in
the units of 512-byte sectors not in bytes.

Reduction of the limit to 1048576 sectors could even cause data
corruption in rare cases - suppose that we have a dm-striped device with
stripe size 768MiB. The target will call dm_set_target_max_io_len with
the value 1572864. The buggy code would reduce it to 1048576. Now, the
dm-core will errorneously split the bios on 1048576-sector boundary
insetad of 1572864-sector boundary and pass these stripe-crossing bios
to the striped target.

Cc: stable@vger.kernel.org # v4.16+
Fixes: 8f50e358153d ("dm: limit the max bio size as BIO_MAX_PAGES * PAGE_SIZE")
Signed-off-by: Mikulas Patocka 
Acked-by: Ming Lei 
Signed-off-by: Mike Snitzer

dm init: fix const confusion for dm_allowed_targets array

2019-04-01T20:16:37+00:00

A non const pointer to const cannot be marked initconst.
Mark the array actually const.

Fixes: 6bbc923dfcf5 dm: add support to directly boot to a mapped device
Signed-off-by: Andi Kleen 
Signed-off-by: Mike Snitzer

dm integrity: make dm_integrity_init and dm_integrity_exit static

2019-04-01T20:16:36+00:00

Fix sparse warnings:

drivers/md/dm-integrity.c:3619:12: warning:
 symbol 'dm_integrity_init' was not declared. Should it be static?
drivers/md/dm-integrity.c:3638:6: warning:
 symbol 'dm_integrity_exit' was not declared. Should it be static?

Signed-off-by: YueHaibing 
Signed-off-by: Mike Snitzer

dm integrity: change memcmp to strncmp in dm_integrity_ctr

2019-04-01T20:11:11+00:00

If the string opt_string is small, the function memcmp can access bytes
that are beyond the terminating nul character. In theory, it could cause
segfault, if opt_string were located just below some unmapped memory.

Change from memcmp to strncmp so that we don't read bytes beyond the end
of the string.

Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

Merge tag 'for-5.1/block-post-20190315' of git://git.kernel.dk/linux-block

2019-03-16T19:36:39+00:00

Pull more block layer changes from Jens Axboe:
 "This is a collection of both stragglers, and fixes that came in after
  I finalized the initial pull. This contains:

   - An MD pull request from Song, with a few minor fixes

   - Set of NVMe patches via Christoph

   - Pull request from Konrad, with a few fixes for xen/blkback

   - pblk fix IO calculation fix (Javier)

   - Segment calculation fix for pass-through (Ming)

   - Fallthrough annotation for blkcg (Mathieu)"

* tag 'for-5.1/block-post-20190315' of git://git.kernel.dk/linux-block: (25 commits)
  blkcg: annotate implicit fall through
  nvme-tcp: support C2HData with SUCCESS flag
  nvmet: ignore EOPNOTSUPP for discard
  nvme: add proper write zeroes setup for the multipath device
  nvme: add proper discard setup for the multipath device
  nvme: remove nvme_ns_config_oncs
  nvme: disable Write Zeroes for qemu controllers
  nvmet-fc: bring Disconnect into compliance with FC-NVME spec
  nvmet-fc: fix issues with targetport assoc_list list walking
  nvme-fc: reject reconnect if io queue count is reduced to zero
  nvme-fc: fix numa_node when dev is null
  nvme-fc: use nr_phys_segments to determine existence of sgl
  nvme-loop: init nvmet_ctrl fatal_err_work when allocate
  nvme: update comment to make the code easier to read
  nvme: put ns_head ref if namespace fails allocation
  nvme-trace: fix cdw10 buffer overrun
  nvme: don't warn on block content change effects
  nvme: add get-feature to admin cmds tracer
  md: Fix failed allocation of md_register_thread
  It's wrong to add len to sector_nr in raid10 reshape twice
  ...

md: Fix failed allocation of md_register_thread

2019-03-12T17:15:18+00:00

mddev->sync_thread can be set to NULL on kzalloc failure downstream.
The patch checks for such a scenario and frees allocated resources.

Committer node:

Added similar fix to raid5.c, as suggested by Guoqing.

Cc: stable@vger.kernel.org # v3.16+
Acked-by: Guoqing Jiang 
Signed-off-by: Aditya Pakki 
Signed-off-by: Song Liu

It's wrong to add len to sector_nr in raid10 reshape twice

2019-03-12T17:15:18+00:00

In reshape_request it already adds len to sector_nr already. It's wrong to add len to
sector_nr again after adding pages to bio. If there is bad block it can't copy one chunk
at a time, it needs to goto read_more. Now the sector_nr is wrong. It can cause data
corruption.

Cc: stable@vger.kernel.org # v3.16+
Signed-off-by: Xiao Ni 
Signed-off-by: Song Liu