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A single fix for x86:

Browse source 
Revert the recent change to the MTRR code which aimed to support
   SEV-SNP guests on Hyper-V. It cuased a regression on XEN Dom0
   kernels.
 
   The underlying issue of MTTR (mis)handling in the x86 code needs some
   deeper investigation and is definitely not 6.2 material.
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Merge tag 'x86-urgent-2023-02-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fix from Thomas Gleixner:
 "A single fix for x86.

  Revert the recent change to the MTRR code which aimed to support
  SEV-SNP guests on Hyper-V. It caused a regression on XEN Dom0 kernels.

  The underlying issue of MTTR (mis)handling in the x86 code needs some
  deeper investigation and is definitely not 6.2 material"

* tag 'x86-urgent-2023-02-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mtrr: Revert 90b926e68f ("x86/pat: Fix pat_x_mtrr_type() for MTRR disabled case")
This commit is contained in:
Linus Torvalds 2023-02-18 17:57:16 -08:00
commit 925cf0457d
1 changed files with 1 additions and 2 deletions
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3
arch/x86/mm/pat/memtype.c
View file

@ -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;