[ Upstream commit 0c8c7c559740d2d8b66048162af6c4dba8f0c88c ]
This is a slight variation on a patch previously proposed by Neil Brown
that never got merged.
Prior to commit 5ceb9d7fda ("NFS: Refactor nfs_lookup_revalidate()"),
any error from nfs_lookup_verify_inode() other than -ESTALE would result
in nfs_lookup_revalidate() returning that error (-ESTALE is mapped to
zero).
Since that commit, all errors result in nfs_lookup_revalidate()
returning zero, resulting in dentries being invalidated where they
previously were not (particularly in the case of -ERESTARTSYS).
Fix it by passing the actual error code to nfs_lookup_revalidate_done(),
and leaving the decision on whether to map the error code to zero or
one to nfs_lookup_revalidate_done().
A simple reproducer is to run the following python code in a
subdirectory of an NFS mount (not in the root of the NFS mount):
---8<---
import os
import multiprocessing
import time
if __name__=="__main__":
multiprocessing.set_start_method("spawn")
count = 0
while True:
try:
os.getcwd()
pool = multiprocessing.Pool(10)
pool.close()
pool.terminate()
count += 1
except Exception as e:
print(f"Failed after {count} iterations")
print(e)
break
---8<---
Prior to commit 5ceb9d7fda, the above code would run indefinitely.
After commit 5ceb9d7fda, it fails almost immediately with -ENOENT.
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
3146a6af82