Hi,
在 2025/04/08 22:38, Meir Elisha 写道:
During recovery/check operations, the process_checks function loops
through available disks to find a 'primary' source with successfully
read data.
If no suitable source disk is found after checking all possibilities,
the 'primary' index will reach conf->raid_disks * 2. Add an explicit
check for this condition after the loop. If no source disk was found,
print an error message and return early to prevent further processing
without a valid primary source.
Signed-off-by: Meir Elisha <meir.elisha@xxxxxxxxxxx>
---
Just to be sure, do you tested this version?
Thanks,
Kuai
Changes from v1:
- Don't fix read errors on recovery/check
This was observed when forcefully disconnecting all iSCSI devices backing
a RAID1 array(using --failfast flag) during a check operation, causing
all reads within process_checks to fail. The resulting kernel oops shows:
BUG: kernel NULL pointer dereference, address: 0000000000000040
RIP: 0010:process_checks+0x25e/0x5e0 [raid1]
Code: ... <4c> 8b 53 40 ... // mov r10,[rbx+0x40]
Call Trace:
process_checks
sync_request_write
raid1d
md_thread
kthread
ret_from_fork
drivers/md/raid1.c | 26 ++++++++++++++++----------
1 file changed, 16 insertions(+), 10 deletions(-)
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 0efc03cea24e..de9bccbe7337 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -2200,14 +2200,9 @@ static int fix_sync_read_error(struct r1bio *r1_bio)
if (!rdev_set_badblocks(rdev, sect, s, 0))
abort = 1;
}
- if (abort) {
- conf->recovery_disabled =
- mddev->recovery_disabled;
- set_bit(MD_RECOVERY_INTR, &mddev->recovery);
- md_done_sync(mddev, r1_bio->sectors, 0);
- put_buf(r1_bio);
+ if (abort)
return 0;
- }
+
/* Try next page */
sectors -= s;
sect += s;
@@ -2346,10 +2341,21 @@ static void sync_request_write(struct mddev *mddev, struct r1bio *r1_bio)
int disks = conf->raid_disks * 2;
struct bio *wbio;
- if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
- /* ouch - failed to read all of that. */
- if (!fix_sync_read_error(r1_bio))
+ if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) {
+ /*
+ * ouch - failed to read all of that.
+ * No need to fix read error for check/repair
+ * because all member disks are read.
+ */
+ if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) ||
+ !fix_sync_read_error(r1_bio)) {
+ conf->recovery_disabled = mddev->recovery_disabled;
+ set_bit(MD_RECOVERY_INTR, &mddev->recovery);
+ md_done_sync(mddev, r1_bio->sectors, 0);
+ put_buf(r1_bio);
return;
+ }
+ }
if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
process_checks(r1_bio);
