On 28/03/17 21:45, Michael Ellerman wrote:
> Alexey Kardashevskiy <a...@ozlabs.ru> writes:
>
>> The CMA pages migration code does not support compound pages at
>> the moment so it performs few tests before proceeding to actual page
>> migration.
>>
>> One of the tests - PageTransHuge() - has VM_BUG_ON_PAGE(PageTail()) as
>> it should be called on head pages. Since we also test for PageCompound(),
>> and it contains PageTail(), we can simply move PageCompound() in front
>> of PageTransHuge() and therefore avoid possible VM_BUG_ON_PAGE.
>>
>> Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
>> ---
>>
>> Some of actual POWER8 systems do crash on that BUG_ON.
>
> So this is:
>
> Fixes: 2e5bbb5461f1 ("KVM: PPC: Book3S HV: Migrate pinned pages out of CMA")
>
> And therefore:
>
> Cc: sta...@vger.kernel.org # v4.9+
>
> ?
May be, first I want to make sure this is enough fix, this is why I
(re)added Balbir in cc list.
--
Alexey
