[PATCH v3 2/5] x86/pvh: Use correct size value in GDT descriptor

From: Ard Biesheuvel
Date: Wed Oct 09 2024 - 12:22:05 EST


From: Ard Biesheuvel <ardb@xxxxxxxxxx>

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@xxxxxxx>
Tested-by: Jason Andryuk <jason.andryuk@xxxxxxx>
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
---
arch/x86/platform/pvh/head.S | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/platform/pvh/head.S b/arch/x86/platform/pvh/head.S
index ce4fd8d33da4..5a196fb3ebd8 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)
--
2.47.0.rc0.187.ge670bccf7e-goog