mdadm test "10ddf-create-fail-rebuild" triggers warnings like the following
[ 215.526357] ------------[ cut here ]------------
[ 215.527243] WARNING: CPU: 18 PID: 1264 at block/bdev.c:617 blkdev_put+0x269/0x350
[ 215.528334] Modules linked in:
[ 215.528806] CPU: 18 PID: 1264 Comm: mdmon Not tainted 6.4.0-rc2+ #768
[ 215.529863] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
[ 215.531464] RIP: 0010:blkdev_put+0x269/0x350
[ 215.532167] Code: ff ff 49 8d 7d 10 e8 56 bf b8 ff 4d 8b 65 10 49 8d bc
24 58 05 00 00 e8 05 be b8 ff 41 83 ac 24 58 05 00 00 01 e9 44 ff ff ff
<0f> 0b e9 52 fe ff ff 0f 0b e9 6b fe ff ff1
[ 215.534780] RSP: 0018:ffffc900040bfbf0 EFLAGS: 00010283
[ 215.535635] RAX: ffff888174001000 RBX: ffff88810b1c3b00 RCX: ffffffff819a4061
[ 215.536645] RDX: dffffc0000000000 RSI: dffffc0000000000 RDI: ffff88810b1c3ba0
[ 215.537657] RBP: ffff88810dbde800 R08: fffffbfff0fca983 R09: fffffbfff0fca983
[ 215.538674] R10: ffffc900040bfbf0 R11: fffffbfff0fca982 R12: ffff88810b1c3b38
[ 215.539687] R13: ffff88810b1c3b10 R14: ffff88810dbdecb8 R15: ffff88810b1c3b00
[ 215.540833] FS: 00007f2aabdff700(0000) GS:ffff888dfb400000(0000) knlGS:0000000000000000
[ 215.541961] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 215.542775] CR2: 00007fa19a85d934 CR3: 000000010c076006 CR4: 0000000000370ee0
[ 215.543814] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 215.544840] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 215.545885] Call Trace:
[ 215.546257] <TASK>
[ 215.546608] export_rdev.isra.63+0x71/0xe0
[ 215.547338] mddev_unlock+0x1b1/0x2d0
[ 215.547898] array_state_store+0x28d/0x450
[ 215.548519] md_attr_store+0xd7/0x150
[ 215.549059] ? __pfx_sysfs_kf_write+0x10/0x10
[ 215.549702] kernfs_fop_write_iter+0x1b9/0x260
[ 215.550351] vfs_write+0x491/0x760
[ 215.550863] ? __pfx_vfs_write+0x10/0x10
[ 215.551445] ? __fget_files+0x156/0x230
[ 215.552053] ksys_write+0xc0/0x160
[ 215.552570] ? __pfx_ksys_write+0x10/0x10
[ 215.553141] ? ktime_get_coarse_real_ts64+0xec/0x100
[ 215.553878] do_syscall_64+0x3a/0x90
[ 215.554403] entry_SYSCALL_64_after_hwframe+0x72/0xdc
[ 215.555125] RIP: 0033:0x7f2aade11847
[ 215.555696] Code: c3 66 90 41 54 49 89 d4 55 48 89 f5 53 89 fb 48 83 ec
10 e8 1b fd ff ff 4c 89 e2 48 89 ee 89 df 41 89 c0 b8 01 00 00 00 0f 05
<48> 3d 00 f0 ff ff 77 35 44 89 c7 48 89 448
[ 215.558398] RSP: 002b:00007f2aabdfeba0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
[ 215.559516] RAX: ffffffffffffffda RBX: 0000000000000010 RCX: 00007f2aade11847
[ 215.560515] RDX: 0000000000000005 RSI: 0000000000438b8b RDI: 0000000000000010
[ 215.561512] RBP: 0000000000438b8b R08: 0000000000000000 R09: 00007f2aaecf0060
[ 215.562511] R10: 000000000e3ba40b R11: 0000000000000293 R12: 0000000000000005
[ 215.563647] R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000c70750
[ 215.564693] </TASK>
[ 215.565029] irq event stamp: 15979
[ 215.565584] hardirqs last enabled at (15991): [<ffffffff811a7432>] __up_console_sem+0x52/0x60
[ 215.566806] hardirqs last disabled at (16000): [<ffffffff811a7417>] __up_console_sem+0x37/0x60
[ 215.568022] softirqs last enabled at (15716): [<ffffffff8277a2db>] __do_softirq+0x3eb/0x531
[ 215.569239] softirqs last disabled at (15711): [<ffffffff810d8f45>] irq_exit_rcu+0x115/0x160
[ 215.570434] ---[ end trace 0000000000000000 ]---
This means export_rdev() calls blkdev_put with a different holder than the
one used by blkdev_get_by_dev(). This is because mddev->major_version == -2
is not a good check for external metadata. Fix this by using
mddev->external instead.
Also, do not clear mddev->external in md_clean(), as the flag might be used
later in export_rdev().
Fixes: 2736e8eeb0cc ("block: use the holder as indication for exclusive opens")
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Song Liu <song@xxxxxxxxxx>
---
drivers/md/md.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index cf3733c90c47..8e7cc2e69bc9 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2458,7 +2458,7 @@ static void export_rdev(struct md_rdev *rdev, struct mddev *mddev)
if (test_bit(AutoDetected, &rdev->flags))
md_autodetect_dev(rdev->bdev->bd_dev);
#endif
- blkdev_put(rdev->bdev, mddev->major_version == -2 ? &claim_rdev : rdev);
+ blkdev_put(rdev->bdev, mddev->external ? &claim_rdev : rdev);
rdev->bdev = NULL;
kobject_put(&rdev->kobj);
}
@@ -6140,7 +6140,7 @@ static void md_clean(struct mddev *mddev)
mddev->resync_min = 0;
mddev->resync_max = MaxSector;
mddev->reshape_position = MaxSector;
- mddev->external = 0;
+ /* we still need mddev->external in export_rdev, do not clear it yet */
mddev->persistent = 0;
mddev->level = LEVEL_NONE;
mddev->clevel[0] = 0;
--
2.34.1
