Andrey Vagin
8515736604
block: fix memory leaks on unplugging block device
All objects, which are allocated in blk_mq_register_disk, must be
released in blk_mq_unregister_disk.
I use a KVM virtual machine and virtio disk to reproduce this issue.
kmemleak: 18 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
$ cat /sys/kernel/debug/kmemleak | head -n 30
unreferenced object 0xffff8800b6636150 (size 8):
comm "kworker/0:2", pid 65, jiffies 4294809903 (age 86.358s)
hex dump (first 8 bytes):
76 69 72 74 69 6f 34 00 virtio4.
backtrace:
[<ffffffff8165d41e>] kmemleak_alloc+0x4e/0xb0
[<ffffffff8118cfc5>] __kmalloc_track_caller+0xf5/0x260
[<ffffffff81155b11>] kstrdup+0x31/0x60
[<ffffffff812242be>] sysfs_new_dirent+0x2e/0x140
[<ffffffff81224678>] create_dir+0x38/0xe0
[<ffffffff812249e3>] sysfs_create_dir_ns+0x73/0xc0
[<ffffffff8130dfa9>] kobject_add_internal+0xc9/0x340
[<ffffffff8130e535>] kobject_add+0x65/0xb0
[<ffffffff813f34f8>] device_add+0x128/0x660
[<ffffffff813f3a4a>] device_register+0x1a/0x20
[<ffffffff813ae6f8>] register_virtio_device+0x98/0xe0
[<ffffffff813b0cce>] virtio_pci_probe+0x12e/0x1c0
[<ffffffff81340675>] local_pci_probe+0x45/0xa0
[<ffffffff81341a51>] pci_device_probe+0x121/0x130
[<ffffffff813f67f7>] driver_probe_device+0x87/0x390
[<ffffffff813f6b3b>] __device_attach+0x3b/0x40
unreferenced object 0xffff8800b65aa1d8 (size 144):
Fixes: 320ae51fee (blk-mq: new multi-queue block IO queueing mechanism)
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>