908272a5e9
commit 02186d8897d49b0afd3c80b6cf23437d91024065 upstream.
A recent fix to the dm_dax_supported() flow uncovered a latent bug. When
dm_get_live_table() fails it is still required to drop the
srcu_read_lock(). Without this change the lvm2 test-suite triggers this
warning:
# lvm2-testsuite --only pvmove-abort-all.sh
WARNING: lock held when returning to user space!
5.9.0-rc5+ #251 Tainted: G OE
------------------------------------------------
lvm/1318 is leaving the kernel with locks still held!
1 lock held by lvm/1318:
#0: ffff9372abb5a340 (&md->io_barrier){....}-{0:0}, at: dm_get_live_table+0x5/0xb0 [dm_mod]
...and later on this hang signature:
INFO: task lvm:1344 blocked for more than 122 seconds.
Tainted: G OE 5.9.0-rc5+ #251
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:lvm state:D stack: 0 pid: 1344 ppid: 1 flags:0x00004000
Call Trace:
__schedule+0x45f/0xa80
? finish_task_switch+0x249/0x2c0
? wait_for_completion+0x86/0x110
schedule+0x5f/0xd0
schedule_timeout+0x212/0x2a0
? __schedule+0x467/0xa80
? wait_for_completion+0x86/0x110
wait_for_completion+0xb0/0x110
__synchronize_srcu+0xd1/0x160
? __bpf_trace_rcu_utilization+0x10/0x10
__dm_suspend+0x6d/0x210 [dm_mod]
dm_suspend+0xf6/0x140 [dm_mod]
Fixes: 7bf7eac8d648 ("dax: Arrange for dax_supported check to span multiple devices")
Cc: <stable@vger.kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Reported-by: Adrian Huang <ahuang12@lenovo.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Tested-by: Adrian Huang <ahuang12@lenovo.com>
Link: https://lore.kernel.org/r/160045867590.25663.7548541079217827340.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
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