[PATCH] md: fix oops in error-handling

During early MD setup (superblock reading), we don't have a personality yet.
But the error-handling code tries to dereference mddev->pers.  Fix.

Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/md/md.c b/drivers/md/md.c
index a5286beddcf51a539aa28f05977927a90e1d1498..b6d16022a53e15e25006814459b9159c10611bad 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -4592,6 +4592,8 @@ void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
                __builtin_return_address(0),__builtin_return_address(1),
                __builtin_return_address(2),__builtin_return_address(3));
 */
+       if (!mddev->pers)
+               return;
        if (!mddev->pers->error_handler)
                return;
        mddev->pers->error_handler(mddev,rdev);