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Subject[PATCH v2 0/2] sched, xfs: Add PF_MEMALLOC_NOLOCKDEP to fix lockdep problem in xfs
Date
 v2:
- Update patch to add the frozen flag check as the XFS_TRANS_NO_WRITECOUNT
check alone is insufficient.

There is a false positive lockdep warning in how the xfs code handle
filesystem freeze:

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(sb_internal);
lock(fs_reclaim);
lock(sb_internal);
lock(fs_reclaim);

*** DEADLOCK ***

This patch series works around this problem by adding a
PF_MEMALLOC_NOLOCKDEP flag and set during filesystem freeze to avoid
the lockdep splat.

Waiman Long (2):
sched: Add PF_MEMALLOC_NOLOCKDEP flag
xfs: Fix false positive lockdep warning with sb_internal & fs_reclaim

fs/xfs/xfs_log.c | 9 +++++++++
fs/xfs/xfs_trans.c | 31 +++++++++++++++++++++++++++----
include/linux/sched.h | 7 +++++++
include/linux/sched/mm.h | 15 ++++++++++-----
4 files changed, 53 insertions(+), 9 deletions(-)

--
2.18.1

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