[PATCH 4.19 074/149] nfs: Fix nfsi->nrequests count error on nfs_inode_remove_request
From: Greg Kroah-Hartman
Date: Mon Nov 04 2019 - 17:00:06 EST
From: ZhangXiaoxu <zhangxiaoxu5@xxxxxxxxxx>
[ Upstream commit 33ea5aaa87cdae0f9af4d6b7ee4f650a1a36fd1d ]
When xfstests testing, there are some WARNING as below:
WARNING: CPU: 0 PID: 6235 at fs/nfs/inode.c:122 nfs_clear_inode+0x9c/0xd8
Modules linked in:
CPU: 0 PID: 6235 Comm: umount.nfs
Hardware name: linux,dummy-virt (DT)
pstate: 60000005 (nZCv daif -PAN -UAO)
pc : nfs_clear_inode+0x9c/0xd8
lr : nfs_evict_inode+0x60/0x78
sp : fffffc000f68fc00
x29: fffffc000f68fc00 x28: fffffe00c53155c0
x27: fffffe00c5315000 x26: fffffc0009a63748
x25: fffffc000f68fd18 x24: fffffc000bfaaf40
x23: fffffc000936d3c0 x22: fffffe00c4ff5e20
x21: fffffc000bfaaf40 x20: fffffe00c4ff5d10
x19: fffffc000c056000 x18: 000000000000003c
x17: 0000000000000000 x16: 0000000000000000
x15: 0000000000000040 x14: 0000000000000228
x13: fffffc000c3a2000 x12: 0000000000000045
x11: 0000000000000000 x10: 0000000000000000
x9 : 0000000000000000 x8 : 0000000000000000
x7 : 0000000000000000 x6 : fffffc00084b027c
x5 : fffffc0009a64000 x4 : fffffe00c0e77400
x3 : fffffc000c0563a8 x2 : fffffffffffffffb
x1 : 000000000000764e x0 : 0000000000000001
Call trace:
nfs_clear_inode+0x9c/0xd8
nfs_evict_inode+0x60/0x78
evict+0x108/0x380
dispose_list+0x70/0xa0
evict_inodes+0x194/0x210
generic_shutdown_super+0xb0/0x220
nfs_kill_super+0x40/0x88
deactivate_locked_super+0xb4/0x120
deactivate_super+0x144/0x160
cleanup_mnt+0x98/0x148
__cleanup_mnt+0x38/0x50
task_work_run+0x114/0x160
do_notify_resume+0x2f8/0x308
work_pending+0x8/0x14
The nrequest should be increased/decreased only if PG_INODE_REF flag
was setted.
But in the nfs_inode_remove_request function, it maybe decrease when
no PG_INODE_REF flag, this maybe lead nrequests count error.
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@xxxxxxxxxx>
Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/nfs/write.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 5ab997912d8d5..117ffd90419e2 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -783,7 +783,6 @@ static void nfs_inode_remove_request(struct nfs_page *req)
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_page *head;
- atomic_long_dec(&nfsi->nrequests);
if (nfs_page_group_sync_on_bit(req, PG_REMOVE)) {
head = req->wb_head;
@@ -796,8 +795,10 @@ static void nfs_inode_remove_request(struct nfs_page *req)
spin_unlock(&mapping->private_lock);
}
- if (test_and_clear_bit(PG_INODE_REF, &req->wb_flags))
+ if (test_and_clear_bit(PG_INODE_REF, &req->wb_flags)) {
nfs_release_request(req);
+ atomic_long_dec(&nfsi->nrequests);
+ }
}
static void
--
2.20.1