From: Ard Biesheuvel <ardb@kernel.org>
Date: Wed, 9 Oct 2024 16:04:41 +0000 (+0200)
Subject: x86/pvh: Use correct size value in GDT descriptor
X-Git-Tag: v6.13-rc1~202^2~4
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=bb12f48cd150666b96858443e0fc26e92bb7e498;p=thirdparty%2Fkernel%2Flinux.git

x86/pvh: Use correct size value in GDT descriptor

The limit field in a GDT descriptor is an inclusive bound, and therefore
one less than the size of the covered range.

Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Tested-by: Jason Andryuk <jason.andryuk@amd.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Message-ID: <20241009160438.3884381-9-ardb+git@google.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
---

diff --git a/arch/x86/platform/pvh/head.S b/arch/x86/platform/pvh/head.S
index ce4fd8d33da46..5a196fb3ebd8a 100644
--- a/arch/x86/platform/pvh/head.S
+++ b/arch/x86/platform/pvh/head.S
@@ -224,7 +224,7 @@ SYM_CODE_END(pvh_start_xen)
 	.section ".init.data","aw"
 	.balign 8
 SYM_DATA_START_LOCAL(gdt)
-	.word gdt_end - gdt_start
+	.word gdt_end - gdt_start - 1
 	.long _pa(gdt_start) /* x86-64 will overwrite if relocated. */
 	.word 0
 SYM_DATA_END(gdt)