Re: [Qemu-devel] Kernel Panic on Yum update

[Gerhard Wiesinger <lists@wiesinger.com>]

On 15.05.2015 10:10, Paolo Bonzini wrote:
>
> On 15/05/2015 09:37, Gerhard Wiesinger wrote:
>> Yes, yum takes memory. But there is ~2.2 GB virt memory available. That
>> should be enough. Therefore I think it is a kernel problem. As in
>> previous crashes on the mailing list there is a lot of swap available
>> (2GB) which isn't touched in ANY way.
>>
>> Under normal conditions without yum:
>> free
>>                total        used        free      shared buff/cache
>> available
>> Mem:         243036      132540       12716       15520 97780       74964
>> Swap:       2064380           0     2064380
> Not all memory is the same.  Some memory cannot be swapped, and some
> memory can be swapped to disk without a swap file (e.g. executables).

Yes, I know the different memory types (pageable, non pageable, etc.).

> Failing an order 0 allocation is weird indeed, but this is a GFP_ATOMIC
> allocation so it's a bit less weird.

Nevertheless the kernel should never go out of non pageable memory if a 
USER process requires memory (which is of course pageable).

Ciao,
Gerhard