NFSv4/flexfiles: Fix layout merge mirror check.

Jonathan Curley · Trond Myklebust · commit dd2fa8247345 · 2025-09-08T14:37:55.000-04:00
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: 660d1eb ("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>
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -293,7 +293,7 @@ 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)

Original file line number	Diff line number	Diff line change
`@@ -293,7 +293,7 @@ ff_lseg_match_mirrors(struct pnfs_layout_segment *l1,`
`293`	`293`	`struct pnfs_layout_segment *l2)`
`294`	`294`	`{`
`295`	`295`	`const struct nfs4_ff_layout_segment *fl1 = FF_LAYOUT_LSEG(l1);`
`296`		`- const struct nfs4_ff_layout_segment *fl2 = FF_LAYOUT_LSEG(l1);`
	`296`	`+ const struct nfs4_ff_layout_segment *fl2 = FF_LAYOUT_LSEG(l2);`
`297`	`297`	`u32 i;`
`298`	`298`
`299`	`299`	`if (fl1->mirror_array_cnt != fl2->mirror_array_cnt)`