Hello,
Last week, while running an rbd test which does a lot of maps and
unmaps (read losetup / losetup -d) with slab debugging enabled, I hit
the attached splat. That 6a byte corresponds to the atomic_long_t
count of the percpu_ref refcnt in request_queue::backing_dev_info::wb,
pointing to a percpu_ref_put() on a freed memory. It hasn't reproduced
since.
After a prolonged stare at rbd (we've just fixed an rbd vs sysfs
lifecycle issue, so I naturally assumed we either missed something or
it had something to do with that patch) I looked wider and concluded
that the most likely place a stray percpu_ref_put() could have come
from was inode_detach_wb(). It's called from __destroy_inode(), which
means iput(), which means bdput().
Looking at __blkdev_put(), the issue becomes clear: we are taking
precautions to flush before calling out to ->release() because, at
least according to the comment, ->release() can free queue; we are
recording owner pointer because put_disk() may free both gendisk and
queue, and then, after all that, we are calling bdput() which may
touch the queue through wb_put() in inode_detach_wb(). (The fun part
is wb_put() is supposed to be a noop for root wbs, but slab debugging
interferes with that by poisoning wb->bdi pointer.)
1514 * dirty data before.
1515 */
1516 bdev_write_inode(bdev);
1517 }
1518 if (bdev->bd_contains == bdev) {
1519 if (disk->fops->release)
1520 disk->fops->release(disk, mode);
1521 }
1522 if (!bdev->bd_openers) {
1523 struct module *owner = disk->fops->owner;
1524
1525 disk_put_part(bdev->bd_part);
1526 bdev->bd_part = NULL;
1527 bdev->bd_disk = NULL;
1528 if (bdev != bdev->bd_contains)
1529 victim = bdev->bd_contains;
1530 bdev->bd_contains = NULL;
1531
1532 put_disk(disk); <-- may free q
1533 module_put(owner);
1534 }
1535 mutex_unlock(&bdev->bd_mutex);
1536 bdput(bdev); <-- may touch q.backing_dev_info.wb
To reproduce, apply the attached patch (systemd-udevd condition is just
a convenience: udev reacts to change events by getting the bdev which
it then has to put), boot with slub_debug=,blkdev_queue and do:
$ sudo modprobe loop
$ sudo losetup /dev/loop0 foo.img
$ sudo dd if=/dev/urandom of=/dev/loop0 bs=1M count=1
$ sudo losetup -d /dev/loop0
$ sudo rmmod loop
(rmmod is key - it's the only way to get loop to do put_disk(). For
rbd, it's just rbd map - dd - rbd unmap.)
In the past we used to reassign to default_backing_dev_info here, but
it was nuked in b83ae6d42143 ("fs: remove mapping->backing_dev_info").
Shortly after that cgroup-specific writebacks patches from Tejun got
merged, adding inode::i_wb and inode_detach_wb() call. The fix seems
to be to detach the inode earlier, but I'm not familiar enough with
cgroups code, so sending my findings instead of a patch. Christoph,
Tejun?
Thanks,
Ilya
[18513.199040] =============================================================================
[18513.199459] BUG blkdev_queue (Not tainted): Poison overwritten
[18513.199459] -----------------------------------------------------------------------------
[18513.199459]
[18513.205765] Disabling lock debugging due to kernel taint
[18513.205765] INFO: 0xffff8800659a05d8-0xffff8800659a05d8. First byte 0x6a instead of 0x6b
[18513.205765] INFO: Allocated in blk_alloc_queue_node+0x28/0x2c0 age=10215 cpu=1 pid=1920
[18513.205765] __slab_alloc.constprop.50+0x4d5/0x540
[18513.205765] kmem_cache_alloc+0x2ba/0x320
[18513.205765] blk_alloc_queue_node+0x28/0x2c0
[18513.205765] blk_mq_init_queue+0x20/0x60
[18513.205765] do_rbd_add.isra.23+0x833/0xd70
[18513.205765] rbd_add+0x1d/0x30
[18513.205765] bus_attr_store+0x25/0x30
[18513.205765] sysfs_kf_write+0x45/0x60
[18513.205765] kernfs_fop_write+0x141/0x190
[18513.205765] __vfs_write+0x28/0xe0
[18513.205765] vfs_write+0xa2/0x180
[18513.205765] SyS_write+0x49/0xa0
[18513.219265] entry_SYSCALL_64_fastpath+0x12/0x6f
[18513.219265] INFO: Freed in blk_free_queue_rcu+0x1c/0x20 age=122 cpu=1 pid=1959
[18513.219265] __slab_free+0x148/0x290
[18513.219265] kmem_cache_free+0x2b7/0x340
[18513.219265] blk_free_queue_rcu+0x1c/0x20
[18513.219265] rcu_process_callbacks+0x2fb/0x820
[18513.219265] __do_softirq+0xd4/0x460
[18513.219265] irq_exit+0x95/0xa0
[18513.219265] smp_apic_timer_interrupt+0x42/0x50
[18513.219265] apic_timer_interrupt+0x81/0x90
[18513.219265] __slab_free+0xb5/0x290
[18513.219265] kmem_cache_free+0x2b7/0x340
[18513.219265] ptlock_free+0x19/0x20
[18513.219265] ___pte_free_tlb+0x22/0x50
[18513.219265] free_pgd_range+0x258/0x440
[18513.219265] free_pgtables+0xc4/0x120
[18513.219265] exit_mmap+0xc3/0x130
[18513.219265] mmput+0x3d/0xf0
[18513.219265] INFO: Slab 0xffffea0001966800 objects=9 used=9 fp=0x (null) flags=0x4000000000004080
[18513.219265] INFO: Object 0xffff8800659a0000 @offset=0 fp=0xffff8800659a6c40
[18513.219265]
[18513.219265] Object ffff8800659a0000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0020: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0030: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0040: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0050: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0060: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0070: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0080: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0090: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a00a0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a00b0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a00c0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a00d0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a00e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a00f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0100: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0110: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0120: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0130: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0140: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0150: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0160: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0170: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0180: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0190: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a01a0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a01b0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a01c0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a01d0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a01e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a01f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0200: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0210: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0220: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0230: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0240: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0250: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0260: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0270: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0280: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0290: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a02a0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a02b0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a02c0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a02d0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a02e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a02f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0300: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0310: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0320: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0330: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0340: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0350: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0360: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0370: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0380: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0390: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a03a0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a03b0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a03c0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a03d0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a03e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a03f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0400: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0410: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0420: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0430: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0440: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0450: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0460: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0470: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0480: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0490: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a04a0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a04b0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a04c0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a04d0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a04e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a04f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0500: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0510: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0520: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0530: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0540: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0550: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0560: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0570: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0580: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0590: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a05a0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a05b0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a05c0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a05d0: 6b 6b 6b 6b 6b 6b 6b 6b 6a 6b 6b 6b 6b 6b 6b 6b kkkkkkkkjkkkkkkk
[18513.219265] Object ffff8800659a05e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a05f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0600: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0610: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0620: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0630: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0640: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0650: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0660: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0670: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0680: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0690: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a06a0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a06b0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a06c0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a06d0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a06e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a06f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0700: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0710: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0720: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0730: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0740: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0750: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0760: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0770: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0780: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0790: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a07a0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a07b0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a07c0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a07d0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a07e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a07f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0800: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0810: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0820: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0830: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0840: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0850: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0860: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0870: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0880: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0890: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a08a0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a08b0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a08c0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a08d0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a08e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a08f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0900: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0910: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0920: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0930: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0940: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0950: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0960: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0970: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0980: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0990: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a09a0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a09b0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a09c0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a09d0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a09e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a09f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0a00: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0a10: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0a20: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0a30: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0a40: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0a50: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0a60: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0a70: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0a80: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0a90: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0aa0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0ab0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0ac0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0ad0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0ae0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0af0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0b00: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0b10: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0b20: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0b30: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0b40: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0b50: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0b60: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0b70: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0b80: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0b90: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0ba0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0bb0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0bc0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0bd0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0be0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0bf0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0c00: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0c10: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0c20: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
[18513.219265] Object ffff8800659a0c30: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5 kkkkkkkkkkkkkkk.
[18513.219265] Redzone ffff8800659a0c40: bb bb bb bb bb bb bb bb ........
[18513.219265] Padding ffff8800659a0d80: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ
[18513.219265] CPU: 1 PID: 1920 Comm: test_librbd_fsx Tainted: G B 4.3.0-rc7-vm+ #129
[18513.219265] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014
[18513.219265] ffff8800659a0000 ffff880065a73b08 ffffffff813750bc ffff88007cb5d440
[18513.219265] ffff880065a73b48 ffffffff8115bd07 0000000000000008 ffff880000000001
[18513.219265] ffff8800659a05d9 ffff88007cb5d440 000000000000006b ffff8800659a0000
[18513.219265] Call Trace:
[18513.219265] [<ffffffff813750bc>] dump_stack+0x4e/0x82
[18513.219265] [<ffffffff8115bd07>] print_trailer+0x147/0x1e0
[18513.219265] [<ffffffff8115c0c5>] check_bytes_and_report+0xc5/0x110
[18513.219265] [<ffffffff8115c2d4>] check_object+0x1c4/0x240
[18513.219265] [<ffffffff8134da48>] ? blk_alloc_queue_node+0x28/0x2c0
[18513.219265] [<ffffffff8115d044>] alloc_debug_processing+0x104/0x180
[18513.219265] [<ffffffff8115ea45>] __slab_alloc.constprop.50+0x4d5/0x540
[18513.219265] [<ffffffff8134da48>] ? blk_alloc_queue_node+0x28/0x2c0
[18513.219265] [<ffffffff8134da48>] ? blk_alloc_queue_node+0x28/0x2c0
[18513.219265] [<ffffffff8115f80a>] kmem_cache_alloc+0x2ba/0x320
[18513.219265] [<ffffffff8134da48>] blk_alloc_queue_node+0x28/0x2c0
[18513.219265] [<ffffffff8135e520>] blk_mq_init_queue+0x20/0x60
[18513.219265] [<ffffffff81430f83>] do_rbd_add.isra.23+0x833/0xd70
[18513.219265] [<ffffffff814314fd>] rbd_add+0x1d/0x30
[18513.219265] [<ffffffff8141aa05>] bus_attr_store+0x25/0x30
[18513.219265] [<ffffffff811eed15>] sysfs_kf_write+0x45/0x60
[18513.219265] [<ffffffff811ee081>] kernfs_fop_write+0x141/0x190
[18513.219265] [<ffffffff81173e38>] __vfs_write+0x28/0xe0
[18513.219265] [<ffffffff8108464a>] ? percpu_down_read+0x5a/0xa0
[18513.219265] [<ffffffff81176be9>] ? __sb_start_write+0xc9/0x110
[18513.219265] [<ffffffff81176be9>] ? __sb_start_write+0xc9/0x110
[18513.219265] [<ffffffff81174522>] vfs_write+0xa2/0x180
[18513.219265] [<ffffffff81175089>] SyS_write+0x49/0xa0
[18513.219265] [<ffffffff8155b257>] entry_SYSCALL_64_fastpath+0x12/0x6f
[18513.219265] FIX blkdev_queue: Restoring 0xffff8800659a05d8-0xffff8800659a05d8=0x6b
[18513.219265]
[18513.219265] FIX blkdev_queue: Marking all objects used
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 565b8dac5782..5a4ff505fd12 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -552,6 +552,7 @@ static void blk_free_queue_rcu(struct rcu_head *rcu_head)
{
struct request_queue *q = container_of(rcu_head, struct request_queue,
rcu_head);
+ printk("freeing q\n");
kmem_cache_free(blk_requestq_cachep, q);
}
diff --git a/fs/block_dev.c b/fs/block_dev.c
index bb0dfb1c7af1..6475dac5f3bc 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1496,6 +1496,8 @@ static int blkdev_open(struct inode * inode, struct file * filp)
return blkdev_get(bdev, filp->f_mode, filp);
}
+#include <linux/delay.h>
+
static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part)
{
struct gendisk *disk = bdev->bd_disk;
@@ -1531,6 +1533,12 @@ static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part)
put_disk(disk);
module_put(owner);
+
+ if (!strcmp(current->comm, "systemd-udevd")) {
+ printk("sleep start %d\n", task_pid_nr(current));
+ ssleep(3);
+ printk("sleep end %d\n", task_pid_nr(current));
+ }
}
mutex_unlock(&bdev->bd_mutex);
bdput(bdev);
diff --git a/fs/inode.c b/fs/inode.c
index 1be5f9003eb3..10625eeb7816 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1490,6 +1490,8 @@ void iput(struct inode *inode)
{
if (!inode)
return;
+ if (inode->i_wb)
+ BUG_ON(atomic_long_read(&inode->i_wb->refcnt.count) == 0x6b6b6b6b6b6b6b6b);
BUG_ON(inode->i_state & I_CLEAR);
retry:
if (atomic_dec_and_lock(&inode->i_count, &inode->i_lock)) {
