linux/block
Tomas Henzl 7b74e91278 block: fix ext_devt_idr handling
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>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:12 -08:00
..
partitions Merge branch 'for-3.8/drivers' of git://git.kernel.dk/linux-block 2012-12-17 13:39:11 -08:00
blk-cgroup.c Merge branch 'for-3.8/core' of git://git.kernel.dk/linux-block 2012-12-17 08:27:23 -08:00
blk-cgroup.h blkcg: implement per-blkg request allocation 2012-06-26 18:42:49 -04:00
blk-core.c block: optionally snapshot page contents to provide stable pages during write 2013-02-21 17:22:20 -08:00
blk-exec.c sched: Move sched.h sysctl bits into separate header 2013-02-07 20:50:54 +01:00
blk-flush.c blk-flush: move the queue kick into 2011-10-24 16:24:31 +02:00
blk-integrity.c bdi: allow block devices to say that they require stable page writes 2013-02-21 17:22:19 -08:00
blk-ioc.c block: uninitialized ioc->nr_tasks triggers WARN_ON 2012-08-01 12:17:27 +02:00
blk-iopoll.c tree-wide: fix assorted typos all over the place 2009-12-04 15:39:55 +01:00
blk-lib.c block: add plug for blkdev_issue_discard 2012-12-14 20:46:04 +01:00
blk-map.c block: re-use existing 'reading' variable instead of checking direction again 2011-12-21 15:27:24 +01:00
blk-merge.c block: Implement support for WRITE SAME 2012-09-20 14:31:45 +02:00
blk-settings.c block: discard granularity might not be power of 2 2012-12-14 20:46:04 +01:00
blk-softirq.c sched, block: Unify cache detection 2012-01-27 13:28:48 +01:00
blk-sysfs.c block: Rename queue dead flag 2012-12-06 14:30:58 +01:00
blk-tag.c block/blk-tag.c: Remove useless kfree 2012-09-12 22:25:12 +02:00
blk-throttle.c block: Rename queue dead flag 2012-12-06 14:30:58 +01:00
blk-timeout.c block: Drop dead function blk_abort_queue() 2012-06-15 08:46:23 +02:00
blk.h block: Avoid that request_fn is invoked on a dead queue 2012-12-06 14:32:01 +01:00
bsg-lib.c bsg: Remove unused function bsg_goose_queue() 2012-12-06 14:33:02 +01:00
bsg.c bsg: fix sysfs link remove warning 2012-02-08 20:02:03 +01:00
cfq-iosched.c block CFQ: avoid moving request to different queue 2012-11-06 12:39:51 +01:00
compat_ioctl.c block: Add BLKROTATIONAL ioctl 2012-01-11 16:29:31 +01:00
deadline-iosched.c deadline: Allow 0ms deadline latency, increase the read speed 2012-12-09 19:19:23 +01:00
elevator.c block: don't request module during elevator init 2013-01-22 16:48:03 -08:00
genhd.c block: fix ext_devt_idr handling 2013-02-27 19:10:12 -08:00
ioctl.c Merge branch 'for-3.7/core' of git://git.kernel.dk/linux-block 2012-10-11 09:04:23 +09:00
Kconfig percpu_rw_semaphore: introduce CONFIG_PERCPU_RWSEM 2012-12-17 17:15:18 -08:00
Kconfig.iosched blkcg: make CONFIG_BLK_CGROUP bool 2012-03-06 21:27:21 +01:00
Makefile separate partition format handling from generic code 2012-01-03 22:54:06 -05:00
noop-iosched.c elevator: make elevator_init_fn() return 0/-errno 2012-03-06 21:27:21 +01:00
partition-generic.c block: fix ext_devt_idr handling 2013-02-27 19:10:12 -08:00
scsi_ioctl.c scsi: Silence unnecessary warnings about ioctl to partition 2012-06-15 12:52:46 +02:00