Re: [PATCH] x86, kdump: Set crashkernel_low automatically

[Yinghai Lu]

On Mon, Mar 11, 2013 at 11:26 AM, Vivek Goyal <vgoyal@xxxxxxxxxx> wrote:
> On Mon, Mar 11, 2013 at 10:58:39AM -0700, Yinghai Lu wrote:
>> On Mon, Mar 11, 2013 at 8:02 AM, Vivek Goyal <vgoyal@xxxxxxxxxx> wrote:
>> >
>> > IOW, wouldn't it be better that crashkernel=X first tries to find
>> > requested amount of memory in lowest memory area available/possible.
>>
>> Yest, that is much better, and user even could stay with old kexec-tools
>> for system that does not tons of memory.
>> And I don't need to mess up with auto setting crashkernel_low or export
>> swiotlb_size() etc.
>>
>> Please check if you are ok with attached one.
>>
> Hi Yinghai,
>
> In mutt your patches are showing as attachment instead of inline. Mutt
> thinks attachment is of type "application/octet-stream". Not sure if
> this is configuration issue on my part or something is going on your
> end.

I sent it via gmail and it only can have attachment instead of inline.

>
> I have few more concerns.
>
> - Are we able to reserve 512MB memory now below 896MB. I remember so
>   far it was broken.

It also depends BIOS memmap layout. some bios put reserved on middle of ram
like just below 512M or just 2G.

>
> - If reserving memory below 896MB fails, we immediately switch to
>   reserving anywhere till MAXMEM. Would it make sense to first try
>   to reserve it below 4G (so that we don't have to worry much about
>   swiotlb or iommu being on).

ok.

Attached again.

Thanks

Yinghai

Attachment: fix_crashkernel_low_v2.patch
Description: Binary data