From: Trond Myklebust <trondmy@gmail.com>
Date: Sun, 7 Apr 2019 13:59:03 -0400
Subject: [PATCH] NFS: Don't call generic_error_remove_page() while holding
 locks
Git-commit: 22876f540bdf19af9e4fca893ce02ba7ee65ebcc
Patch-mainline: v5.2
References: bsc#1170457

The NFS read code can trigger writeback while holding the page lock.
If an error then triggers a call to nfs_write_error_remove_page(),
we can deadlock.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Acked-by: NeilBrown <neilb@suse.com>

---
 fs/nfs/write.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -605,9 +605,8 @@ try_again:
 static void nfs_write_error_remove_page(struct nfs_page *req)
 {
 	nfs_unlock_request(req);
+	SetPageError(req->wb_page);
 	nfs_end_page_writeback(req);
-	generic_error_remove_page(page_file_mapping(req->wb_page),
-				  req->wb_page);
 	nfs_release_request(req);
 }