mirror of
https://github.com/raspberrypi/linux.git
synced 2025-12-06 01:49:46 +00:00
cd1385c095
[ Upstream commitc97738a960] In commit8d3d7e2b35, we changed xfs_qm_dqpurge to bail out if we can't lock the dquot buf to flush the dquot. This prevents the AIL from blocking on the dquot, but it also forgets to clear the FREEING flag on its way out. A subsequent purge attempt will see the FREEING flag is set and bail out, which leads to dqpurge_all failing to purge all the dquots. (copy-pasting from Dave Chinner's identical patch) This was found by inspection after having xfs/305 hang 1 in ~50 iterations in a quotaoff operation: [ 8872.301115] xfs_quota D13888 92262 91813 0x00004002 [ 8872.302538] Call Trace: [ 8872.303193] __schedule+0x2d2/0x780 [ 8872.304108] ? do_raw_spin_unlock+0x57/0xd0 [ 8872.305198] schedule+0x6e/0xe0 [ 8872.306021] schedule_timeout+0x14d/0x300 [ 8872.307060] ? __next_timer_interrupt+0xe0/0xe0 [ 8872.308231] ? xfs_qm_dqusage_adjust+0x200/0x200 [ 8872.309422] schedule_timeout_uninterruptible+0x2a/0x30 [ 8872.310759] xfs_qm_dquot_walk.isra.0+0x15a/0x1b0 [ 8872.311971] xfs_qm_dqpurge_all+0x7f/0x90 [ 8872.313022] xfs_qm_scall_quotaoff+0x18d/0x2b0 [ 8872.314163] xfs_quota_disable+0x3a/0x60 [ 8872.315179] kernel_quotactl+0x7e2/0x8d0 [ 8872.316196] ? __do_sys_newstat+0x51/0x80 [ 8872.317238] __x64_sys_quotactl+0x1e/0x30 [ 8872.318266] do_syscall_64+0x46/0x90 [ 8872.319193] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 8872.320490] RIP: 0033:0x7f46b5490f2a [ 8872.321414] Code: Bad RIP value. Returning -EAGAIN from xfs_qm_dqpurge() without clearing the XFS_DQ_FREEING flag means the xfs_qm_dqpurge_all() code can never free the dquot, and we loop forever waiting for the XFS_DQ_FREEING flag to go away on the dquot that leaked it via -EAGAIN. Fixes:8d3d7e2b35("xfs: trylock underlying buffer on dquot flush") Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
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
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.