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

[Minchan Kim]

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>