The patch titled
Subject: zram: failing to decompress is WARN_ON worthy
has been added to the -mm tree. Its filename is
zram-failing-to-decompress-is-warn_on-worthy.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/zram-failing-to-decompress-is-warn_on-worthy.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/zram-failing-to-decompress-is-warn_on-worthy.patch
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------------------------------------------------------
From: Douglas Anderson <dianders@xxxxxxxxxxxx>
Subject: zram: failing to decompress is WARN_ON worthy
If we fail to decompress in zram it's a pretty serious problem. We were
entrusted to be able to decompress the old data but we failed. Either
we've got some crazy bug in the compression code or we've got memory
corruption.
At the moment, when this happens the log looks like this:
ERR kernel: [ 1833.099861] zram: Decompression failed! err=-22, page=336112
ERR kernel: [ 1833.099881] zram: Decompression failed! err=-22, page=336112
ALERT kernel: [ 1833.099886] Read-error on swap-device (253:0:2688896)
It is true that we have an "ALERT" level log in there, but (at least to
me) it feels like even this isn't enough to impart the seriousness of this
error. Let's convert to a WARN_ON. Note that WARN_ON is automatically
"unlikely" so we can simply replace the old annotation with the new one.
Link: https://lkml.kernel.org/r/20200917174059.1.If09c882545dbe432268f7a67a4d4cfcb6caace4f@changeid
Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Acked-by: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@xxxxxxxxx>
Cc: Sonny Rao <sonnyrao@xxxxxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/block/zram/zram_drv.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/block/zram/zram_drv.c~zram-failing-to-decompress-is-warn_on-worthy
+++ a/drivers/block/zram/zram_drv.c
@@ -1268,7 +1268,7 @@ static int __zram_bvec_read(struct zram
zram_slot_unlock(zram, index);
/* Should NEVER happen. Return bio error if it does. */
- if (unlikely(ret))
+ if (WARN_ON(ret))
pr_err("Decompression failed! err=%d, page=%u\n", ret, index);
return ret;
_
Patches currently in -mm which might be from dianders@xxxxxxxxxxxx are
zram-failing-to-decompress-is-warn_on-worthy.patch
