diff options
| author | Tomas Henzl <thenzl@redhat.com> | 2013-02-27 17:03:32 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-03-04 06:03:35 +0800 |
| commit | c5799187ac9e45170a0ddfe1df074227b9a0b8f6 (patch) | |
| tree | 38e1fe84b963cb6dfb034061166d2f35556c6fbe | |
| parent | 68719e23c62aff61969713cd2158dd0fa37d45cd (diff) | |
block: fix ext_devt_idr handling
commit 7b74e912785a11572da43292786ed07ada7e3e0c upstream.
While adding and removing a lot of disks disks and partitions this
sometimes shows up:
WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xc9/0x130() (Not tainted)
Hardware name:
sysfs: cannot create duplicate filename '/dev/block/259:751'
Modules linked in: raid1 autofs4 bnx2fc cnic uio fcoe libfcoe libfc 8021q scsi_transport_fc scsi_tgt garp stp llc sunrpc cpufreq_ondemand powernow_k8 freq_table mperf ipv6 dm_mirror dm_region_hash dm_log power_meter microcode dcdbas serio_raw amd64_edac_mod edac_core edac_mce_amd i2c_piix4 i2c_core k10temp bnx2 sg ixgbe dca mdio ext4 mbcache jbd2 dm_round_robin sr_mod cdrom sd_mod crc_t10dif ata_generic pata_acpi pata_atiixp ahci mptsas mptscsih mptbase scsi_transport_sas dm_multipath dm_mod [last unloaded: scsi_wait_scan]
Pid: 44103, comm: async/16 Not tainted 2.6.32-195.el6.x86_64 #1
Call Trace:
warn_slowpath_common+0x87/0xc0
warn_slowpath_fmt+0x46/0x50
sysfs_add_one+0xc9/0x130
sysfs_do_create_link+0x12b/0x170
sysfs_create_link+0x13/0x20
device_add+0x317/0x650
idr_get_new+0x13/0x50
add_partition+0x21c/0x390
rescan_partitions+0x32b/0x470
sd_open+0x81/0x1f0 [sd_mod]
__blkdev_get+0x1b6/0x3c0
blkdev_get+0x10/0x20
register_disk+0x155/0x170
add_disk+0xa6/0x160
sd_probe_async+0x13b/0x210 [sd_mod]
add_wait_queue+0x46/0x60
async_thread+0x102/0x250
default_wake_function+0x0/0x20
async_thread+0x0/0x250
kthread+0x96/0xa0
child_rip+0xa/0x20
kthread+0x0/0xa0
child_rip+0x0/0x20
This most likely happens because dev_t is freed while the number is
still used and idr_get_new() is not protected on every use. The fix
adds a mutex where it wasn't before and moves the dev_t free function so
it is called after device del.
Signed-off-by: Tomas Henzl <thenzl@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | block/genhd.c | 6 | ||||
| -rw-r--r-- | block/partition-generic.c | 2 |
2 files changed, 6 insertions, 2 deletions
diff --git a/block/genhd.c b/block/genhd.c index 3993ebf4135..35d0290885a 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -422,14 +422,18 @@ int blk_alloc_devt(struct hd_struct *part, dev_t *devt) do { if (!idr_pre_get(&ext_devt_idr, GFP_KERNEL)) return -ENOMEM; + mutex_lock(&ext_devt_mutex); rc = idr_get_new(&ext_devt_idr, part, &idx); + mutex_unlock(&ext_devt_mutex); } while (rc == -EAGAIN); if (rc) return rc; if (idx > MAX_EXT_DEVT) { + mutex_lock(&ext_devt_mutex); idr_remove(&ext_devt_idr, idx); + mutex_unlock(&ext_devt_mutex); return -EBUSY; } @@ -646,7 +650,6 @@ void del_gendisk(struct gendisk *disk) disk_part_iter_exit(&piter); invalidate_partition(disk, 0); - blk_free_devt(disk_to_dev(disk)->devt); set_capacity(disk, 0); disk->flags &= ~GENHD_FL_UP; @@ -664,6 +667,7 @@ void del_gendisk(struct gendisk *disk) if (!sysfs_deprecated) sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk))); device_del(disk_to_dev(disk)); + blk_free_devt(disk_to_dev(disk)->devt); } EXPORT_SYMBOL(del_gendisk); diff --git a/block/partition-generic.c b/block/partition-generic.c index f1d14519cc0..1cb4deca132 100644 --- a/block/partition-generic.c +++ b/block/partition-generic.c @@ -249,11 +249,11 @@ void delete_partition(struct gendisk *disk, int partno) if (!part) return; - blk_free_devt(part_devt(part)); rcu_assign_pointer(ptbl->part[partno], NULL); rcu_assign_pointer(ptbl->last_lookup, NULL); kobject_put(part->holder_dir); device_del(part_to_dev(part)); + blk_free_devt(part_devt(part)); hd_struct_put(part); } |