NFSv4/flexfiles: Fix layout merge mirror check.

[ Upstream commit dd2fa82473453661d12723c46c9f43d9876a7efd ]

Typo in ff_lseg_match_mirrors makes the diff ineffective. This results
in merge happening all the time. Merge happening all the time is
problematic because it marks lsegs invalid. Marking lsegs invalid
causes all outstanding IO to get restarted with EAGAIN and connections
to get closed.

Closing connections constantly triggers race conditions in the RDMA
implementation...

Fixes: 660d1eb22301c ("pNFS/flexfile: Don't merge layout segments if the mirrors don't match")
Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index 69496aab9583e608442e0f945af742c20e781bc5..6469846971966b0fa3e1ebab89317529684bf4d1 100644 (file)
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -292,7 +292,7 @@ ff_lseg_match_mirrors(struct pnfs_layout_segment *l1,
                struct pnfs_layout_segment *l2)
 {
        const struct nfs4_ff_layout_segment *fl1 = FF_LAYOUT_LSEG(l1);
-       const struct nfs4_ff_layout_segment *fl2 = FF_LAYOUT_LSEG(l1);
+       const struct nfs4_ff_layout_segment *fl2 = FF_LAYOUT_LSEG(l2);
        u32 i;
 
        if (fl1->mirror_array_cnt != fl2->mirror_array_cnt)