linux-kernel - [PATCH 1/4] xen/PVH: Replace GDT

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Date:   Mon, 30 Apr 2018 12:23:36 -0400
From:   Boris Ostrovsky <boris.ostrovsky@...cle.com>
To:     linux-kernel@...r.kernel.org, xen-devel@...ts.xenproject.org
Cc:     jgross@...e.com, Boris Ostrovsky <boris.ostrovsky@...cle.com>,
        stable@...r.kernel.org
Subject: [PATCH 1/4] xen/PVH: Replace GDT_ENTRY with explicit constant

Latest binutils release (2.29.1) will no longer allow proper computation
of GDT entries on 32-bits, with warning:

arch/x86/xen/xen-pvh.S: Assembler messages:
arch/x86/xen/xen-pvh.S:150: Warning: shift count out of range (32 is not between 0 and 31)
arch/x86/xen/xen-pvh.S:150: Warning: shift count out of range (40 is not between 0 and 31)
arch/x86/xen/xen-pvh.S:150: Warning: shift count out of range (32 is not between 0 and 31)
arch/x86/xen/xen-pvh.S:152: Warning: shift count out of range (32 is not between 0 and 31)
arch/x86/xen/xen-pvh.S:152: Warning: shift count out of range (40 is not between 0 and 31)
arch/x86/xen/xen-pvh.S:152: Warning: shift count out of range (32 is not between 0 and 31)

Use explicit value of the entry instead of using GDT_ENTRY() macro.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@...cle.com>
Cc: stable@...r.kernel.org
---
 arch/x86/xen/xen-pvh.S | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/x86/xen/xen-pvh.S b/arch/x86/xen/xen-pvh.S
index e1a5fbe..934f7d4 100644
--- a/arch/x86/xen/xen-pvh.S
+++ b/arch/x86/xen/xen-pvh.S
@@ -145,11 +145,11 @@ gdt_start:
 	.quad 0x0000000000000000            /* NULL descriptor */
 	.quad 0x0000000000000000            /* reserved */
 #ifdef CONFIG_X86_64
-	.quad GDT_ENTRY(0xa09a, 0, 0xfffff) /* __KERNEL_CS */
+	.quad 0x00af9a000000ffff            /* __BOOT_CS */
 #else
-	.quad GDT_ENTRY(0xc09a, 0, 0xfffff) /* __KERNEL_CS */
+	.quad 0x00cf9a000000ffff            /* __BOOT_CS */
 #endif
-	.quad GDT_ENTRY(0xc092, 0, 0xfffff) /* __KERNEL_DS */
+	.quad 0x00cf92000000ffff            /* __BOOT_DS */
 gdt_end:
 
 	.balign 4
-- 
2.9.3