linux-stable.git/drivers/md/raid5.c, branch linux-5.0.y

md/raid: raid5 preserve the writeback action after the parity check

2019-05-25T16:22:31+00:00

commit b2176a1dfb518d870ee073445d27055fea64dfb8 upstream.

The problem is that any 'uptodate' vs 'disks' check is not precise
in this path. Put a "WARN_ON(!test_bit(R5_UPTODATE, &dev->flags)" on the
device that might try to kick off writes and then skip the action.
Better to prevent the raid driver from taking unexpected action *and* keep
the system alive vs killing the machine with BUG_ON.

Note: fixed warning reported by kbuild test robot 

Signed-off-by: Dan Williams 
Signed-off-by: Nigel Croxon 
Signed-off-by: Song Liu 
Signed-off-by: Greg Kroah-Hartman

Revert "Don't jump to compute_result state from check_result state"

2019-05-25T16:22:30+00:00

commit a25d8c327bb41742dbd59f8c545f59f3b9c39983 upstream.

This reverts commit 4f4fd7c5798bbdd5a03a60f6269cf1177fbd11ef.

Cc: Dan Williams 
Cc: Nigel Croxon 
Cc: Xiao Ni 
Signed-off-by: Song Liu 
Signed-off-by: Greg Kroah-Hartman

Don't jump to compute_result state from check_result state

2019-05-16T17:40:27+00:00

commit 4f4fd7c5798bbdd5a03a60f6269cf1177fbd11ef upstream.

Changing state from check_state_check_result to
check_state_compute_result not only is unsafe but also doesn't
appear to serve a valid purpose.  A raid6 check should only be
pushing out extra writes if doing repair and a mis-match occurs.
The stripe dev management will already try and do repair writes
for failing sectors.

This patch makes the raid6 check_state_check_result handling
work more like raid5's.  If somehow too many failures for a
check, just quit the check operation for the stripe.  When any
checks pass, don't try and use check_state_compute_result for
a purpose it isn't needed for and is unsafe for.  Just mark the
stripe as in sync for passing its parity checks and let the
stripe dev read/write code and the bad blocks list do their
job handling I/O errors.

Repro steps from Xiao:

These are the steps to reproduce this problem:
1. redefined OPT_MEDIUM_ERR_ADDR to 12000 in scsi_debug.c
2. insmod scsi_debug.ko dev_size_mb=11000  max_luns=1 num_tgts=1
3. mdadm --create /dev/md127 --level=6 --raid-devices=5 /dev/sde1 /dev/sde2 /dev/sde3 /dev/sde5 /dev/sde6
sde is the disk created by scsi_debug
4. echo "2" >/sys/module/scsi_debug/parameters/opts
5. raid-check

It panic:
[ 4854.730899] md: data-check of RAID array md127
[ 4854.857455] sd 5:0:0:0: [sdr] tag#80 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[ 4854.859246] sd 5:0:0:0: [sdr] tag#80 Sense Key : Medium Error [current]
[ 4854.860694] sd 5:0:0:0: [sdr] tag#80 Add. Sense: Unrecovered read error
[ 4854.862207] sd 5:0:0:0: [sdr] tag#80 CDB: Read(10) 28 00 00 00 2d 88 00 04 00 00
[ 4854.864196] print_req_error: critical medium error, dev sdr, sector 11656 flags 0
[ 4854.867409] sd 5:0:0:0: [sdr] tag#100 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[ 4854.869469] sd 5:0:0:0: [sdr] tag#100 Sense Key : Medium Error [current]
[ 4854.871206] sd 5:0:0:0: [sdr] tag#100 Add. Sense: Unrecovered read error
[ 4854.872858] sd 5:0:0:0: [sdr] tag#100 CDB: Read(10) 28 00 00 00 2e e0 00 00 08 00
[ 4854.874587] print_req_error: critical medium error, dev sdr, sector 12000 flags 4000
[ 4854.876456] sd 5:0:0:0: [sdr] tag#101 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[ 4854.878552] sd 5:0:0:0: [sdr] tag#101 Sense Key : Medium Error [current]
[ 4854.880278] sd 5:0:0:0: [sdr] tag#101 Add. Sense: Unrecovered read error
[ 4854.881846] sd 5:0:0:0: [sdr] tag#101 CDB: Read(10) 28 00 00 00 2e e8 00 00 08 00
[ 4854.883691] print_req_error: critical medium error, dev sdr, sector 12008 flags 4000
[ 4854.893927] sd 5:0:0:0: [sdr] tag#166 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[ 4854.896002] sd 5:0:0:0: [sdr] tag#166 Sense Key : Medium Error [current]
[ 4854.897561] sd 5:0:0:0: [sdr] tag#166 Add. Sense: Unrecovered read error
[ 4854.899110] sd 5:0:0:0: [sdr] tag#166 CDB: Read(10) 28 00 00 00 2e e0 00 00 10 00
[ 4854.900989] print_req_error: critical medium error, dev sdr, sector 12000 flags 0
[ 4854.902757] md/raid:md127: read error NOT corrected!! (sector 9952 on sdr1).
[ 4854.904375] md/raid:md127: read error NOT corrected!! (sector 9960 on sdr1).
[ 4854.906201] ------------[ cut here ]------------
[ 4854.907341] kernel BUG at drivers/md/raid5.c:4190!

raid5.c:4190 above is this BUG_ON:

    handle_parity_checks6()
        ...
        BUG_ON(s->uptodate < disks - 1); /* We don't need Q to recover */

Cc:  # v3.16+
OriginalAuthor: David Jeffery 
Cc: Xiao Ni 
Tested-by: David Jeffery 
Signed-off-by: David Jeffy 
Signed-off-by: Nigel Croxon 
Signed-off-by: Song Liu 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

md: Fix failed allocation of md_register_thread

2019-03-23T19:11:38+00:00

commit e406f12dde1a8375d77ea02d91f313fb1a9c6aec upstream.

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 
Signed-off-by: Greg Kroah-Hartman

md/raid5: fix 'out of memory' during raid cache recovery

2019-01-28T19:44:40+00:00

This fixes the case when md array assembly fails because of raid cache recovery
unable to allocate a stripe, despite attempts to replay stripes and increase
cache size. This happens because stripes released by r5c_recovery_replay_stripes
and raid5_set_cache_size don't become available for allocation immediately.
Released stripes first are placed on conf->released_stripes list and require
md thread to merge them on conf->inactive_list before they can be allocated.

Patch allows final allocation attempt during cache recovery to wait for
new stripes to become availabe for allocation.

Cc: linux-raid@vger.kernel.org
Cc: Shaohua Li 
Cc: linux-stable  # 4.10+
Fixes: b4c625c67362 ("md/r5cache: r5cache recovery: part 1")
Signed-off-by: Alexei Naberezhnov 
Signed-off-by: Song Liu

raid5: block failing device if raid will be failed

2018-09-28T18:13:15+00:00

Currently there is an inconsistency for failing the member drives
for arrays with different RAID levels. For RAID456 - there is a possibility
to fail all of the devices. However - for other RAID levels - kernel blocks
removing the member drive, if the operation results in array's FAIL state
(EBUSY is returned). For example - removing last drive from RAID1 is not
possible.
This kind of blocker was never implemented for raid456 and we cannot see
the reason why.

We had tested following patch and did not observe any regression, so do you
have any comments/reasons for current approach, or we can send the proper
patch for this?

Signed-off-by: Mariusz Tkaczyk 
Signed-off-by: Shaohua Li

md/raid5-cache: disable reshape completely

2018-09-01T00:38:09+00:00

We don't support reshape yet if an array supports log device. Previously we
determine the fact by checking ->log. However, ->log could be NULL after a log
device is removed, but the array is still marked to support log device. Don't
allow reshape in this case too. User can disable log device support by setting
'consistency_policy' to 'resync' then do reshape.

Reported-by: Xiao Ni 
Tested-by: Xiao Ni 
Signed-off-by: Shaohua Li

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

2018-08-18T23:48:07+00:00

Pull input updates from Dmitry Torokhov:

 - a new driver for Rohm BU21029 touch controller

 - new bitmap APIs: bitmap_alloc, bitmap_zalloc and bitmap_free

 - updates to Atmel, eeti. pxrc and iforce drivers

 - assorted driver cleanups and fixes.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (57 commits)
  MAINTAINERS: Add PhoenixRC Flight Controller Adapter
  Input: do not use WARN() in input_alloc_absinfo()
  Input: mark expected switch fall-throughs
  Input: raydium_i2c_ts - use true and false for boolean values
  Input: evdev - switch to bitmap API
  Input: gpio-keys - switch to bitmap_zalloc()
  Input: elan_i2c_smbus - cast sizeof to int for comparison
  bitmap: Add bitmap_alloc(), bitmap_zalloc() and bitmap_free()
  md: Avoid namespace collision with bitmap API
  dm: Avoid namespace collision with bitmap API
  Input: pm8941-pwrkey - add resin entry
  Input: pm8941-pwrkey - abstract register offsets and event code
  Input: iforce - reorganize joystick configuration lists
  Input: atmel_mxt_ts - move completion to after config crc is updated
  Input: atmel_mxt_ts - don't report zero pressure from T9
  Input: atmel_mxt_ts - zero terminate config firmware file
  Input: atmel_mxt_ts - refactor config update code to add context struct
  Input: atmel_mxt_ts - config CRC may start at T71
  Input: atmel_mxt_ts - remove unnecessary debug on ENOMEM
  Input: atmel_mxt_ts - remove duplicate setup of ABS_MT_PRESSURE
  ...

md/raid5: fix data corruption of replacements after originals dropped

2018-08-02T18:22:06+00:00

During raid5 replacement, the stripes can be marked with R5_NeedReplace
flag. Data can be read from being-replaced devices and written to
replacing spares without reading all other devices. (It's 'replace'
mode. s.replacing = 1) If a being-replaced device is dropped, the
replacement progress will be interrupted and resumed with pure recovery
mode. However, existing stripes before being interrupted cannot read
from the dropped device anymore. It prints lots of WARN_ON messages.
And it results in data corruption because existing stripes write
problematic data into its replacement device and update the progress.

\# Erase disks (1MB + 2GB)
dd if=/dev/zero of=/dev/sda bs=1MB count=2049
dd if=/dev/zero of=/dev/sdb bs=1MB count=2049
dd if=/dev/zero of=/dev/sdc bs=1MB count=2049
dd if=/dev/zero of=/dev/sdd bs=1MB count=2049
mdadm -C /dev/md0 -amd -R -l5 -n3 -x0 /dev/sd[abc] -z 2097152
\# Ensure array stores non-zero data
dd if=/root/data_4GB.iso of=/dev/md0 bs=1MB
\# Start replacement
mdadm /dev/md0 -a /dev/sdd
mdadm /dev/md0 --replace /dev/sda

Then, Hot-plug out /dev/sda during recovery, and wait for recovery done.
echo check > /sys/block/md0/md/sync_action
cat /sys/block/md0/md/mismatch_cnt # it will be greater than 0.

Soon after you hot-plug out /dev/sda, you will see many WARN_ON
messages. The replacement recovery will be interrupted shortly. After
the recovery finishes, it will result in data corruption.

Actually, it's just an unhandled case of replacement. In commit
 (md/raid5: fix interaction of 'replace' and 'recovery'.),
if a NeedReplace device is not UPTODATE then that is an error, the
commit just simply print WARN_ON but also mark these corrupted stripes
with R5_WantReplace. (it means it's ready for writes.)

To fix this case, we can leverage 'sync and replace' mode mentioned in
commit <9a3e1101b827> (md/raid5: detect and handle replacements during
recovery.). We can add logics to detect and use 'sync and replace' mode
for these stripes.

Reported-by: Alex Chen 
Reviewed-by: Alex Wu 
Reviewed-by: Chung-Chiang Cheng 
Signed-off-by: BingJing Chang 
Signed-off-by: Shaohua Li

md: Avoid namespace collision with bitmap API

2018-08-01T22:49:39+00:00

bitmap API (include/linux/bitmap.h) has 'bitmap' prefix for its methods.

On the other hand MD bitmap API is special case.
Adding 'md' prefix to it to avoid name space collision.

No functional changes intended.

Signed-off-by: Andy Shevchenko 
Acked-by: Shaohua Li 
Signed-off-by: Dmitry Torokhov