From: Mariusz Tkaczyk mariusz.tkaczyk@linux.intel.com
commit 57668f0a4cc4083a120cc8c517ca0055c4543b59 upstream.
Raid456 module had allowed to achieve failed state. It was fixed by fb73b357fb9 ("raid5: block failing device if raid will be failed"). This fix introduces a bug, now if raid5 fails during IO, it may result with a hung task without completion. Faulty flag on the device is necessary to process all requests and is checked many times, mainly in analyze_stripe(). Allow to set faulty on drive again and set MD_BROKEN if raid is failed.
As a result, this level is allowed to achieve failed state again, but communication with userspace (via -EBUSY status) will be preserved.
This restores possibility to fail array via #mdadm --set-faulty command and will be fixed by additional verification on mdadm side.
Reproduction steps: mdadm -CR imsm -e imsm -n 3 /dev/nvme[0-2]n1 mdadm -CR r5 -e imsm -l5 -n3 /dev/nvme[0-2]n1 --assume-clean mkfs.xfs /dev/md126 -f mount /dev/md126 /mnt/root/
fio --filename=/mnt/root/file --size=5GB --direct=1 --rw=randrw --bs=64k --ioengine=libaio --iodepth=64 --runtime=240 --numjobs=4 --time_based --group_reporting --name=throughput-test-job --eta-newline=1 &
echo 1 > /sys/block/nvme2n1/device/device/remove echo 1 > /sys/block/nvme1n1/device/device/remove
[ 1475.787779] Call Trace: [ 1475.793111] __schedule+0x2a6/0x700 [ 1475.799460] schedule+0x38/0xa0 [ 1475.805454] raid5_get_active_stripe+0x469/0x5f0 [raid456] [ 1475.813856] ? finish_wait+0x80/0x80 [ 1475.820332] raid5_make_request+0x180/0xb40 [raid456] [ 1475.828281] ? finish_wait+0x80/0x80 [ 1475.834727] ? finish_wait+0x80/0x80 [ 1475.841127] ? finish_wait+0x80/0x80 [ 1475.847480] md_handle_request+0x119/0x190 [ 1475.854390] md_make_request+0x8a/0x190 [ 1475.861041] generic_make_request+0xcf/0x310 [ 1475.868145] submit_bio+0x3c/0x160 [ 1475.874355] iomap_dio_submit_bio.isra.20+0x51/0x60 [ 1475.882070] iomap_dio_bio_actor+0x175/0x390 [ 1475.889149] iomap_apply+0xff/0x310 [ 1475.895447] ? iomap_dio_bio_actor+0x390/0x390 [ 1475.902736] ? iomap_dio_bio_actor+0x390/0x390 [ 1475.909974] iomap_dio_rw+0x2f2/0x490 [ 1475.916415] ? iomap_dio_bio_actor+0x390/0x390 [ 1475.923680] ? atime_needs_update+0x77/0xe0 [ 1475.930674] ? xfs_file_dio_aio_read+0x6b/0xe0 [xfs] [ 1475.938455] xfs_file_dio_aio_read+0x6b/0xe0 [xfs] [ 1475.946084] xfs_file_read_iter+0xba/0xd0 [xfs] [ 1475.953403] aio_read+0xd5/0x180 [ 1475.959395] ? _cond_resched+0x15/0x30 [ 1475.965907] io_submit_one+0x20b/0x3c0 [ 1475.972398] __x64_sys_io_submit+0xa2/0x180 [ 1475.979335] ? do_io_getevents+0x7c/0xc0 [ 1475.986009] do_syscall_64+0x5b/0x1a0 [ 1475.992419] entry_SYSCALL_64_after_hwframe+0x65/0xca [ 1476.000255] RIP: 0033:0x7f11fc27978d [ 1476.006631] Code: Bad RIP value. [ 1476.073251] INFO: task fio:3877 blocked for more than 120 seconds.
Cc: stable@vger.kernel.org Fixes: fb73b357fb9 ("raid5: block failing device if raid will be failed") Reviewd-by: Xiao Ni xni@redhat.com Signed-off-by: Mariusz Tkaczyk mariusz.tkaczyk@linux.intel.com Signed-off-by: Song Liu song@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/md/raid5.c | 47 ++++++++++++++++++++++------------------------- 1 file changed, 22 insertions(+), 25 deletions(-)
--- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -686,17 +686,17 @@ int raid5_calc_degraded(struct r5conf *c return degraded; }
-static int has_failed(struct r5conf *conf) +static bool has_failed(struct r5conf *conf) { - int degraded; + int degraded = conf->mddev->degraded;
- if (conf->mddev->reshape_position == MaxSector) - return conf->mddev->degraded > conf->max_degraded; + if (test_bit(MD_BROKEN, &conf->mddev->flags)) + return true;
- degraded = raid5_calc_degraded(conf); - if (degraded > conf->max_degraded) - return 1; - return 0; + if (conf->mddev->reshape_position != MaxSector) + degraded = raid5_calc_degraded(conf); + + return degraded > conf->max_degraded; }
struct stripe_head * @@ -2877,34 +2877,31 @@ static void raid5_error(struct mddev *md unsigned long flags; pr_debug("raid456: error called\n");
+ pr_crit("md/raid:%s: Disk failure on %s, disabling device.\n", + mdname(mddev), bdevname(rdev->bdev, b)); + spin_lock_irqsave(&conf->device_lock, flags); + set_bit(Faulty, &rdev->flags); + clear_bit(In_sync, &rdev->flags); + mddev->degraded = raid5_calc_degraded(conf);
- if (test_bit(In_sync, &rdev->flags) && - mddev->degraded == conf->max_degraded) { - /* - * Don't allow to achieve failed state - * Don't try to recover this device - */ + if (has_failed(conf)) { + set_bit(MD_BROKEN, &conf->mddev->flags); conf->recovery_disabled = mddev->recovery_disabled; - spin_unlock_irqrestore(&conf->device_lock, flags); - return; + + pr_crit("md/raid:%s: Cannot continue operation (%d/%d failed).\n", + mdname(mddev), mddev->degraded, conf->raid_disks); + } else { + pr_crit("md/raid:%s: Operation continuing on %d devices.\n", + mdname(mddev), conf->raid_disks - mddev->degraded); }
- set_bit(Faulty, &rdev->flags); - clear_bit(In_sync, &rdev->flags); - mddev->degraded = raid5_calc_degraded(conf); spin_unlock_irqrestore(&conf->device_lock, flags); set_bit(MD_RECOVERY_INTR, &mddev->recovery);
set_bit(Blocked, &rdev->flags); set_mask_bits(&mddev->sb_flags, 0, BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_PENDING)); - pr_crit("md/raid:%s: Disk failure on %s, disabling device.\n" - "md/raid:%s: Operation continuing on %d devices.\n", - mdname(mddev), - bdevname(rdev->bdev, b), - mdname(mddev), - conf->raid_disks - mddev->degraded); r5c_update_on_rdev_error(mddev, rdev); }