Re: [PATCH] x86_64: early memtest to find bad ram

From: Yinghai Lu
Date: Fri Mar 21 2008 - 20:04:21 EST


On Fri, Mar 21, 2008 at 5:03 AM, Ingo Molnar <mingo@xxxxxxx> wrote:
>
> * Yinghai Lu <yhlu.kernel.send@xxxxxxxxx> wrote:
>
> > do simple memtest after init_memory_mapping
> >
> > use find_e820_area_size to find all ram range that is not reserved.
> >
> > and do some simple bits test to find some bad ram.
> >
> > if find some bad ram, use reserve_early to exclude that range.
>
> very nice patch! I always thought that this was the proper way to do
> memtest - and we could in fact also do something like this after SMP
> bringup, and hit the memory bus via multiple CPUs. [that will need a
> different enumeration though than e820 maps]
or
1. core0/node0 check all memory at first
2. every core0 will check all memory later one by one.

>
> one structural observation: please make this unified functionality, so
> that 32-bit kernels can make use of it too.

that will need to use PAE to switch 2G windows ....

>
> a small style nit from scripts/checkpatch.pl:
>
>
> > +// printk(KERN_DEBUG "find_e820_area_size : e820 %d [%llx, %lx]\n", i, ei->addr, ei_last);
>
> remove such lines or make them pr_debug(). (checkpatch also found more
> such cases)
>
> also, please add a CONFIG_BOOTPARAM_MEMTEST=y option so that
> distributions can enable this by default in their debug kernels.
>
> i've applied your current version to get some testing, please send delta
> patches against x86/latest.

thanks. will submit delta patch.

YH
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/