Re: [PATCH] zram: Failing to decompress is WARN_ON worthy

From: Minchan Kim
Date: Fri Sep 18 2020 - 10:46:29 EST

On Thu, Sep 17, 2020 at 05:41:20PM -0700, Douglas Anderson wrote:
> 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.
> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Acked-by: Minchan Kim <minchan@xxxxxxxxxx>