<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/block/genhd.c, branch v3.10.2</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>block: do not pass disk names as format strings</title>
<updated>2013-07-13T18:42:26+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2013-07-03T22:01:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=88ce7cf76ced99962699d0ebb4d47d6a88b94c29'/>
<id>88ce7cf76ced99962699d0ebb4d47d6a88b94c29</id>
<content type='text'>
commit ffc8b30866879ed9ba62bd0a86fecdbd51cd3d19 upstream.

Disk names may contain arbitrary strings, so they must not be
interpreted as format strings.  It seems that only md allows arbitrary
strings to be used for disk names, but this could allow for a local
memory corruption from uid 0 into ring 0.

CVE-2013-2851

Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit ffc8b30866879ed9ba62bd0a86fecdbd51cd3d19 upstream.

Disk names may contain arbitrary strings, so they must not be
interpreted as format strings.  It seems that only md allows arbitrary
strings to be used for disk names, but this could allow for a local
memory corruption from uid 0 into ring 0.

CVE-2013-2851

Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>driver core: handle user namespaces properly with the uid/gid devtmpfs change</title>
<updated>2013-04-11T18:43:29+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2013-04-11T18:43:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=4e4098a3e08783cfd75f9fcdab276dc1d46931da'/>
<id>4e4098a3e08783cfd75f9fcdab276dc1d46931da</id>
<content type='text'>
Now that devtmpfs is caring about uid/gid, we need to use the correct
internal types so users who have USER_NS enabled will have things work
properly for them.

Thanks to Eric for pointing this out, and the patch review.

Reported-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: Kay Sievers &lt;kay@vrfy.org&gt;
Cc: Ming Lei &lt;ming.lei@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Now that devtmpfs is caring about uid/gid, we need to use the correct
internal types so users who have USER_NS enabled will have things work
properly for them.

Thanks to Eric for pointing this out, and the patch review.

Reported-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: Kay Sievers &lt;kay@vrfy.org&gt;
Cc: Ming Lei &lt;ming.lei@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>driver core: add uid and gid to devtmpfs</title>
<updated>2013-04-08T15:21:48+00:00</updated>
<author>
<name>Kay Sievers</name>
<email>kay@vrfy.org</email>
</author>
<published>2013-04-06T16:56:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3c2670e6515cf584810f417db9b00992c8b2d75a'/>
<id>3c2670e6515cf584810f417db9b00992c8b2d75a</id>
<content type='text'>
Some drivers want to tell userspace what uid and gid should be used for
their device nodes, so allow that information to percolate through the
driver core to userspace in order to make this happen.  This means that
some systems (i.e.  Android and friends) will not need to even run a
udev-like daemon for their device node manager and can just rely in
devtmpfs fully, reducing their footprint even more.

Signed-off-by: Kay Sievers &lt;kay@vrfy.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Some drivers want to tell userspace what uid and gid should be used for
their device nodes, so allow that information to percolate through the
driver core to userspace in order to make this happen.  This means that
some systems (i.e.  Android and friends) will not need to even run a
udev-like daemon for their device node manager and can just rely in
devtmpfs fully, reducing their footprint even more.

Signed-off-by: Kay Sievers &lt;kay@vrfy.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: convert to idr_alloc()</title>
<updated>2013-02-28T03:10:15+00:00</updated>
<author>
<name>Tejun Heo</name>
<email>tj@kernel.org</email>
</author>
<published>2013-02-28T01:03:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=bab998d62f12db12b3ddf1e06b2ecd4ed9e7ae45'/>
<id>bab998d62f12db12b3ddf1e06b2ecd4ed9e7ae45</id>
<content type='text'>
Convert to the much saner new idr interface.  Both bsg and genhd
protect idr w/ mutex making preloading unnecessary.

Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Acked-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Convert to the much saner new idr interface.  Both bsg and genhd
protect idr w/ mutex making preloading unnecessary.

Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Acked-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: fix synchronization and limit check in blk_alloc_devt()</title>
<updated>2013-02-28T03:10:14+00:00</updated>
<author>
<name>Tejun Heo</name>
<email>tj@kernel.org</email>
</author>
<published>2013-02-28T01:03:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ce23bba842aee98092225d9576dba47c82352521'/>
<id>ce23bba842aee98092225d9576dba47c82352521</id>
<content type='text'>
idr allocation in blk_alloc_devt() wasn't synchronized against lookup
and removal, and its limit check was off by one - 1 &lt;&lt; MINORBITS is
the number of minors allowed, not the maximum allowed minor.

Add locking and rename MAX_EXT_DEVT to NR_EXT_DEVT and fix limit
checking.

Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Acked-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
idr allocation in blk_alloc_devt() wasn't synchronized against lookup
and removal, and its limit check was off by one - 1 &lt;&lt; MINORBITS is
the number of minors allowed, not the maximum allowed minor.

Add locking and rename MAX_EXT_DEVT to NR_EXT_DEVT and fix limit
checking.

Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Acked-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: fix ext_devt_idr handling</title>
<updated>2013-02-28T03:10:12+00:00</updated>
<author>
<name>Tomas Henzl</name>
<email>thenzl@redhat.com</email>
</author>
<published>2013-02-28T01:03:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7b74e912785a11572da43292786ed07ada7e3e0c'/>
<id>7b74e912785a11572da43292786ed07ada7e3e0c</id>
<content type='text'>
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 &lt;thenzl@redhat.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;thenzl@redhat.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block/genhd.c: apply pm_runtime_set_memalloc_noio on block devices</title>
<updated>2013-02-24T01:50:16+00:00</updated>
<author>
<name>Ming Lei</name>
<email>ming.lei@canonical.com</email>
</author>
<published>2013-02-23T00:34:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=25e823c8c37d123b77ce12a042da889e6bb5f9d1'/>
<id>25e823c8c37d123b77ce12a042da889e6bb5f9d1</id>
<content type='text'>
Apply the introduced pm_runtime_set_memalloc_noio on block device so
that PM core will teach mm to not allocate memory with GFP_IOFS when
calling the runtime_resume and runtime_suspend callback for block
devices and its ancestors.

Signed-off-by: Ming Lei &lt;ming.lei@canonical.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Minchan Kim &lt;minchan@kernel.org&gt;
Cc: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Cc: Oliver Neukum &lt;oneukum@suse.de&gt;
Cc: Jiri Kosina &lt;jiri.kosina@suse.com&gt;
Cc: Mel Gorman &lt;mel@csn.ul.ie&gt;
Cc: KAMEZAWA Hiroyuki &lt;kamezawa.hiroyu@jp.fujitsu.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.cz&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: "Rafael J. Wysocki" &lt;rjw@sisk.pl&gt;
Cc: Greg KH &lt;greg@kroah.com&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Cc: David Decotigny &lt;david.decotigny@google.com&gt;
Cc: Tom Herbert &lt;therbert@google.com&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Apply the introduced pm_runtime_set_memalloc_noio on block device so
that PM core will teach mm to not allocate memory with GFP_IOFS when
calling the runtime_resume and runtime_suspend callback for block
devices and its ancestors.

Signed-off-by: Ming Lei &lt;ming.lei@canonical.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Minchan Kim &lt;minchan@kernel.org&gt;
Cc: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Cc: Oliver Neukum &lt;oneukum@suse.de&gt;
Cc: Jiri Kosina &lt;jiri.kosina@suse.com&gt;
Cc: Mel Gorman &lt;mel@csn.ul.ie&gt;
Cc: KAMEZAWA Hiroyuki &lt;kamezawa.hiroyu@jp.fujitsu.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.cz&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: "Rafael J. Wysocki" &lt;rjw@sisk.pl&gt;
Cc: Greg KH &lt;greg@kroah.com&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Cc: David Decotigny &lt;david.decotigny@google.com&gt;
Cc: Tom Herbert &lt;therbert@google.com&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: prevent race/cleanup</title>
<updated>2012-12-19T19:36:10+00:00</updated>
<author>
<name>Derek Basehore</name>
<email>dbasehore@chromium.org</email>
</author>
<published>2012-12-18T20:27:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=12c2bdb232168511c8dd54d6626549391a228918'/>
<id>12c2bdb232168511c8dd54d6626549391a228918</id>
<content type='text'>
Remove a race condition which causes a warning in disk_clear_events.  This
is a race between disk_clear_events() and disk_flush_events().
ev-&gt;clearing will be altered by disk_flush_events() even though we are
blocking event checking through disk_flush_events().  If this happens
after ev-&gt;clearing was cleared for disk_clear_events(), this can cause the
WARN_ON_ONCE() in that function to be triggered.

This change also has disk_clear_events() not go through a workqueue.
Since we have to wait for the work to complete, we should just call the
function directly.  Also, since this work cannot be put on a freezable
workqueue, it will have to contend with increased demand, so calling the
function directly avoids this.

[akpm@linux-foundation.org: fix spello in comment]
Signed-off-by: Derek Basehore &lt;dbasehore@chromium.org&gt;
Cc: Mandeep Singh Baines &lt;msb@chromium.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Remove a race condition which causes a warning in disk_clear_events.  This
is a race between disk_clear_events() and disk_flush_events().
ev-&gt;clearing will be altered by disk_flush_events() even though we are
blocking event checking through disk_flush_events().  If this happens
after ev-&gt;clearing was cleared for disk_clear_events(), this can cause the
WARN_ON_ONCE() in that function to be triggered.

This change also has disk_clear_events() not go through a workqueue.
Since we have to wait for the work to complete, we should just call the
function directly.  Also, since this work cannot be put on a freezable
workqueue, it will have to contend with increased demand, so calling the
function directly avoids this.

[akpm@linux-foundation.org: fix spello in comment]
Signed-off-by: Derek Basehore &lt;dbasehore@chromium.org&gt;
Cc: Mandeep Singh Baines &lt;msb@chromium.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: remove deadlock in disk_clear_events</title>
<updated>2012-12-19T19:36:05+00:00</updated>
<author>
<name>Derek Basehore</name>
<email>dbasehore@chromium.org</email>
</author>
<published>2012-12-18T20:27:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=aea24a8bbc81c8b404e4e293fb37aefaf388d35d'/>
<id>aea24a8bbc81c8b404e4e293fb37aefaf388d35d</id>
<content type='text'>
In disk_clear_events, do not put work on system_nrt_freezable_wq.
Instead, put it on system_nrt_wq.

There is a race between probing a usb and suspending the device.  Since
probing a usb calls disk_clear_events, which puts work on a frozen
workqueue, probing cannot finish after the workqueue is frozen.  However,
suspending cannot finish until the usb probe is finished, so we get a
deadlock, causing the system to reboot.

The way to reproduce this bug is to wake up from suspend with a usb
storage device plugged in, or plugging in a usb storage device right
before suspend.  The window of time is on the order of time it takes to
probe the usb device.  As long as the workqueues are frozen before the
call to add_disk within sd_probe_async finishes, there will be a deadlock
(which calls blkdev_get, sd_open, check_disk_change, then
disk_clear_events).  This is not difficult to reproduce after figuring out
the timings.

[akpm@linux-foundation.org: fix up comment]
Signed-off-by: Derek Basehore &lt;dbasehore@chromium.org&gt;
Reviewed-by: Mandeep Singh Baines &lt;msb@chromium.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In disk_clear_events, do not put work on system_nrt_freezable_wq.
Instead, put it on system_nrt_wq.

There is a race between probing a usb and suspending the device.  Since
probing a usb calls disk_clear_events, which puts work on a frozen
workqueue, probing cannot finish after the workqueue is frozen.  However,
suspending cannot finish until the usb probe is finished, so we get a
deadlock, causing the system to reboot.

The way to reproduce this bug is to wake up from suspend with a usb
storage device plugged in, or plugging in a usb storage device right
before suspend.  The window of time is on the order of time it takes to
probe the usb device.  As long as the workqueues are frozen before the
call to add_disk within sd_probe_async finishes, there will be a deadlock
(which calls blkdev_get, sd_open, check_disk_change, then
disk_clear_events).  This is not difficult to reproduce after figuring out
the timings.

[akpm@linux-foundation.org: fix up comment]
Signed-off-by: Derek Basehore &lt;dbasehore@chromium.org&gt;
Reviewed-by: Mandeep Singh Baines &lt;msb@chromium.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'for-3.8/drivers' of git://git.kernel.dk/linux-block</title>
<updated>2012-12-17T21:39:11+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2012-12-17T21:39:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9228ff90387e276ad67b10c0eb525c9d6a57d5e9'/>
<id>9228ff90387e276ad67b10c0eb525c9d6a57d5e9</id>
<content type='text'>
Pull block driver update from Jens Axboe:
 "Now that the core bits are in, here are the driver bits for 3.8.  The
  branch contains:

   - A huge pile of drbd bits that were dumped from the 3.7 merge
     window.  Following that, it was both made perfectly clear that
     there is going to be no more over-the-wall pulls and how the
     situation on individual pulls can be improved.

   - A few cleanups from Akinobu Mita for drbd and cciss.

   - Queue improvement for loop from Lukas.  This grew into adding a
     generic interface for waiting/checking an even with a specific
     lock, allowing this to be pulled out of md and now loop and drbd is
     also using it.

   - A few fixes for xen back/front block driver from Roger Pau Monne.

   - Partition improvements from Stephen Warren, allowing partiion UUID
     to be used as an identifier."

* 'for-3.8/drivers' of git://git.kernel.dk/linux-block: (609 commits)
  drbd: update Kconfig to match current dependencies
  drbd: Fix drbdsetup wait-connect, wait-sync etc... commands
  drbd: close race between drbd_set_role and drbd_connect
  drbd: respect no-md-barriers setting also when changed online via disk-options
  drbd: Remove obsolete check
  drbd: fixup after wait_even_lock_irq() addition to generic code
  loop: Limit the number of requests in the bio list
  wait: add wait_event_lock_irq() interface
  xen-blkfront: free allocated page
  xen-blkback: move free persistent grants code
  block: partition: msdos: provide UUIDs for partitions
  init: reduce PARTUUID min length to 1 from 36
  block: store partition_meta_info.uuid as a string
  cciss: use check_signature()
  cciss: cleanup bitops usage
  drbd: use copy_highpage
  drbd: if the replication link breaks during handshake, keep retrying
  drbd: check return of kmalloc in receive_uuids
  drbd: Broadcast sync progress no more often than once per second
  drbd: don't try to clear bits once the disk has failed
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull block driver update from Jens Axboe:
 "Now that the core bits are in, here are the driver bits for 3.8.  The
  branch contains:

   - A huge pile of drbd bits that were dumped from the 3.7 merge
     window.  Following that, it was both made perfectly clear that
     there is going to be no more over-the-wall pulls and how the
     situation on individual pulls can be improved.

   - A few cleanups from Akinobu Mita for drbd and cciss.

   - Queue improvement for loop from Lukas.  This grew into adding a
     generic interface for waiting/checking an even with a specific
     lock, allowing this to be pulled out of md and now loop and drbd is
     also using it.

   - A few fixes for xen back/front block driver from Roger Pau Monne.

   - Partition improvements from Stephen Warren, allowing partiion UUID
     to be used as an identifier."

* 'for-3.8/drivers' of git://git.kernel.dk/linux-block: (609 commits)
  drbd: update Kconfig to match current dependencies
  drbd: Fix drbdsetup wait-connect, wait-sync etc... commands
  drbd: close race between drbd_set_role and drbd_connect
  drbd: respect no-md-barriers setting also when changed online via disk-options
  drbd: Remove obsolete check
  drbd: fixup after wait_even_lock_irq() addition to generic code
  loop: Limit the number of requests in the bio list
  wait: add wait_event_lock_irq() interface
  xen-blkfront: free allocated page
  xen-blkback: move free persistent grants code
  block: partition: msdos: provide UUIDs for partitions
  init: reduce PARTUUID min length to 1 from 36
  block: store partition_meta_info.uuid as a string
  cciss: use check_signature()
  cciss: cleanup bitops usage
  drbd: use copy_highpage
  drbd: if the replication link breaks during handshake, keep retrying
  drbd: check return of kmalloc in receive_uuids
  drbd: Broadcast sync progress no more often than once per second
  drbd: don't try to clear bits once the disk has failed
  ...
</pre>
</div>
</content>
</entry>
</feed>
