From:   Thomas Gleixner <tglx@linutronix.de>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     linux-kernel@vger.kernel.org, x86@kernel.org
Subject: [GIT pull] x86/urgent for v6.2
References: <167676366161.269954.1941292974323519398.tglx@xen13>
Message-ID: <167676366450.269954.1214202439225962646.tglx@xen13>
Content-Type: text/plain; charset="utf-8"
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MIME-Version: 1.0
Date:   Sun, 19 Feb 2023 00:42:26 +0100 (CET)
Precedence: bulk

Linus,

please pull the latest x86/urgent branch from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-urgent-2023-=
02-19

up to:  f9f57da2c2d1: x86/mtrr: Revert 90b926e68f50 ("x86/pat: Fix pat_x_mtrr=
_type() for MTRR disabled case")


A single fix for x86:

  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.

Thanks,

	tglx

------------------>
Juergen Gross (1):
      x86/mtrr: Revert 90b926e68f50 ("x86/pat: Fix pat_x_mtrr_type() for MTRR=
 disabled case")


 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;
=20
 		mtrr_type =3D mtrr_type_lookup(start, end, &uniform);
-		if (mtrr_type !=3D MTRR_TYPE_WRBACK &&
-		    mtrr_type !=3D MTRR_TYPE_INVALID)
+		if (mtrr_type !=3D MTRR_TYPE_WRBACK)
 			return _PAGE_CACHE_MODE_UC_MINUS;
=20
 		return _PAGE_CACHE_MODE_WB;