Squash: fix another kernel panic that arose after the last rebase.

asomers · asomers · commit af3c9b1c5aea · 2026-03-04T06:45:35.000-07:00
diff --git a/module/zfs/dbuf.c b/module/zfs/dbuf.c
@@ -5307,7 +5307,7 @@ dbuf_remap_impl(dnode_t *dn, blkptr_t *bp, krwlock_t *rw, dmu_tx_t *tx)
 		 * avoid lock contention, only grab it when we are actually
 		 * changing the BP.
 		 */
-		if (rw != NULL && !rw_tryupgrade(rw)) {
+		if (rw != NULL && !RW_WRITE_HELD(rw) && !rw_tryupgrade(rw)) {
 			rw_exit(rw);
 			rw_enter(rw, RW_WRITER);
 		}

Original file line number	Diff line number	Diff line change
`@@ -5307,7 +5307,7 @@ dbuf_remap_impl(dnode_t dn, blkptr_t bp, krwlock_t rw, dmu_tx_t tx)`
`5307`	`5307`	`* avoid lock contention, only grab it when we are actually`
`5308`	`5308`	`* changing the BP.`
`5309`	`5309`	`*/`
`5310`		`- if (rw != NULL && !rw_tryupgrade(rw)) {`
	`5310`	`+ if (rw != NULL && !RW_WRITE_HELD(rw) && !rw_tryupgrade(rw)) {`
`5311`	`5311`	`rw_exit(rw);`
`5312`	`5312`	`rw_enter(rw, RW_WRITER);`
`5313`	`5313`	`}`