From: J. Bruce Fields <[email protected]> commit 70438afbf17e5194dd607dd17759560a363b7bb4 upstream.
We forgot to unregister the nfs4_xattr_large_entry_shrinker. That leaves the global list of shrinkers corrupted after unload of the nfs module, after which possibly unrelated code that calls register_shrinker() or unregister_shrinker() gets a BUG() with "supervisor write access in kernel mode". And similarly for the nfs4_xattr_large_entry_lru. Reported-by: Kris Karas <[email protected]> Tested-By: Kris Karas <[email protected]> Fixes: 95ad37f90c33 "NFSv4.2: add client side xattr caching." Signed-off-by: J. Bruce Fields <[email protected]> CC: [email protected] Signed-off-by: Anna Schumaker <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- fs/nfs/nfs42xattr.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/nfs/nfs42xattr.c +++ b/fs/nfs/nfs42xattr.c @@ -1048,8 +1048,10 @@ out4: void nfs4_xattr_cache_exit(void) { + unregister_shrinker(&nfs4_xattr_large_entry_shrinker); unregister_shrinker(&nfs4_xattr_entry_shrinker); unregister_shrinker(&nfs4_xattr_cache_shrinker); + list_lru_destroy(&nfs4_xattr_large_entry_lru); list_lru_destroy(&nfs4_xattr_entry_lru); list_lru_destroy(&nfs4_xattr_cache_lru); kmem_cache_destroy(nfs4_xattr_cache_cachep);
