lkml.org 
[lkml]   [2023]   [Feb]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH v2 5/8] x86/mtrr: revert commit 90b926e68f50
From
On 10.02.23 19:59, Linux regression tracking (Thorsten Leemhuis) wrote:
> Hi, this is your Linux kernel regression tracker.
>
> On 09.02.23 08:22, Juergen Gross wrote:
>> Commit 90b926e68f50 ("x86/pat: Fix pat_x_mtrr_type() for MTRR disabled
>> case") has introduced a regression with Xen.
>>
>> Revert the patch.
>
> That regression you refer to is afaics one I'm tracking[1] that was
> introduced this cycle. That makes me wonder: could this patch be applied
> directly to fix the issue quickly? Or are patches 1 to 4 needed as well
> (or the whole series?) to avoid other problems?

Patches 1-4 are needed, too, as otherwise the issue claimed to be fixed
with patch 5 would show up again.

I'm working on addressing the comments I've received.


Juergen

>
> Ciao, Thorsten
>
> [1]
> https://lore.kernel.org/all/4fe9541e-4d4c-2b2a-f8c8-2d34a7284930@nerdbynature.de/
>
> P.S.: BTW; let me tell regzbot to monitor this thread:
>
> #regzbot ^backmonitor:
> https://lore.kernel.org/all/4fe9541e-4d4c-2b2a-f8c8-2d34a7284930@nerdbynature.de/
>
>
>> Signed-off-by: Juergen Gross <jgross@suse.com>
>> ---
>> arch/x86/mm/pat/memtype.c | 3 +--
>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c
>> index fb4b1b5e0dea..46de9cf5c91d 100644
>> --- a/arch/x86/mm/pat/memtype.c
>> +++ b/arch/x86/mm/pat/memtype.c
>> @@ -387,8 +387,7 @@ static unsigned long pat_x_mtrr_type(u64 start, u64 end,
>> u8 mtrr_type, uniform;
>>
>> mtrr_type = mtrr_type_lookup(start, end, &uniform);
>> - if (mtrr_type != MTRR_TYPE_WRBACK &&
>> - mtrr_type != MTRR_TYPE_INVALID)
>> + if (mtrr_type != MTRR_TYPE_WRBACK)
>> return _PAGE_CACHE_MODE_UC_MINUS;
>>
>> return _PAGE_CACHE_MODE_WB;

[unhandled content-type:application/pgp-keys][unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2023-03-27 00:19    [W:1.177 / U:0.332 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site