UBI: print a warning if too many PEBs are corrupted
There was a bug report recently where UBI prints:
UBI error: ubi_attach_mtd_dev: failed to attach by scanning, error -22
error messages and refuses to attach a PEB. It turned out to be a
buggy flash driver which returned garbage to almost every UBI read.
This patch makes UBI print a better message in such cases. Namely,
if UBI finds 8 or more corrupted PEBs, it prints a warning and
lists the corrupted PEBs.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/ubi/scan.c b/drivers/mtd/ubi/scan.c
index 93361ea..e7161ad 100644
--- a/drivers/mtd/ubi/scan.c
+++ b/drivers/mtd/ubi/scan.c
@@ -75,9 +75,10 @@
dbg_bld("add to free: PEB %d, EC %d", pnum, ec);
else if (list == &si->erase)
dbg_bld("add to erase: PEB %d, EC %d", pnum, ec);
- else if (list == &si->corr)
+ else if (list == &si->corr) {
dbg_bld("add to corrupted: PEB %d, EC %d", pnum, ec);
- else if (list == &si->alien)
+ si->corr_count += 1;
+ } else if (list == &si->alien)
dbg_bld("add to alien: PEB %d, EC %d", pnum, ec);
else
BUG();
@@ -938,6 +939,19 @@
ubi_msg("empty MTD device detected");
/*
+ * Few corrupted PEBs are not a problem and may be just a result of
+ * unclean reboots. However, many of them may indicate some problems
+ * with the flash HW or driver. Print a warning in this case.
+ */
+ if (si->corr_count >= 8 || si->corr_count >= ubi->peb_count / 4) {
+ ubi_warn("%d PEBs are corrupted", si->corr_count);
+ printk(KERN_WARNING "corrupted PEBs are:");
+ list_for_each_entry(seb, &si->corr, u.list)
+ printk(KERN_CONT " %d", seb->pnum);
+ printk(KERN_CONT "\n");
+ }
+
+ /*
* In case of unknown erase counter we use the mean erase counter
* value.
*/