Re: single bit flip detector.

[Patrick McLean <pmclean@cs.ubishops.ca>]

Dave Jones wrote:
> On Tue, Aug 01, 2006 at 07:51:09PM -0400, Dave Jones wrote:
>  > I'm going for the record of 'most times a patch gets submitted in one day'.
>  > And to think we were complaining that patches don't get enough review ? :)
>  > If every change had this much polish, we'd be awesome.
> 
> Sigh. Spaces before printk. Whatever next.
> I am now officially bored of seeing this patch.
> 
> 		Dave
> 
> 
> In case where we detect a single bit has been flipped, we spew
> the usual slab corruption message, which users instantly think
> is a kernel bug.  In a lot of cases, single bit errors are
> down to bad memory, or other hardware failure.
> 
> This patch adds an extra line to the slab debug messages
> in those cases, in the hope that users will try memtest before
> they report a bug.
> 
> 000: 6b 6b 6b 6b 6a 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
> Single bit error detected. Possibly bad RAM. Run memtest86.
> 
> Signed-off-by: Dave Jones <davej@redhat.com>
> 
> +		if (errors && !(errors & (errors-1))) {
> +			printk(KERN_ERR "Single bit error detected. Probably bad RAM.\n");
> +#ifdef CONFIG_X86

#if defined(CONFIG_X86) || defined(CONFIG_X86_64)

memtest86+ runs fine on x86_64 machines as well.

> +			printk(KERN_ERR "Run memtest86+ or a similar memory test tool.\n");
> +#else
> +			printk(KERN_ERR "Run a memory test tool.\n");