From: Michael Matz <matz@suse.de>
Date: Wed, 8 Mar 2006 05:55:48 +0000 (-0800)
Subject: [PATCH] fix kexec asm
X-Git-Tag: v2.6.16-rc6~59
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2ec5e3a867d63d04932e11c6097f63760d9be3fe;p=linux-2.6

[PATCH] fix kexec asm

While testing kexec and kdump we hit problems where the new kernel would
freeze or instantly reboot.  The easiest way to trigger it was to kexec a
kernel compiled for CONFIG_M586 on an athlon cpu.  Compiling for CONFIG_MK7
instead would work fine.

The patch fixes a few problems with the kexec inline asm.

Signed-off-by: Chris Mason <mason@suse.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/arch/i386/kernel/machine_kexec.c b/arch/i386/kernel/machine_kexec.c
index a912fed484..f73d7374a2 100644
--- a/arch/i386/kernel/machine_kexec.c
+++ b/arch/i386/kernel/machine_kexec.c
@@ -116,13 +116,13 @@ static void load_segments(void)
 	__asm__ __volatile__ (
 		"\tljmp $"STR(__KERNEL_CS)",$1f\n"
 		"\t1:\n"
-		"\tmovl $"STR(__KERNEL_DS)",%eax\n"
-		"\tmovl %eax,%ds\n"
-		"\tmovl %eax,%es\n"
-		"\tmovl %eax,%fs\n"
-		"\tmovl %eax,%gs\n"
-		"\tmovl %eax,%ss\n"
-		);
+		"\tmovl $"STR(__KERNEL_DS)",%%eax\n"
+		"\tmovl %%eax,%%ds\n"
+		"\tmovl %%eax,%%es\n"
+		"\tmovl %%eax,%%fs\n"
+		"\tmovl %%eax,%%gs\n"
+		"\tmovl %%eax,%%ss\n"
+		::: "eax", "memory");
 #undef STR
 #undef __STR
 }
diff --git a/arch/x86_64/kernel/machine_kexec.c b/arch/x86_64/kernel/machine_kexec.c
index 89fab51e20..25ac8a3faa 100644
--- a/arch/x86_64/kernel/machine_kexec.c
+++ b/arch/x86_64/kernel/machine_kexec.c
@@ -140,7 +140,7 @@ static void load_segments(void)
 		"\tmovl %0,%%ss\n"
 		"\tmovl %0,%%fs\n"
 		"\tmovl %0,%%gs\n"
-		: : "a" (__KERNEL_DS)
+		: : "a" (__KERNEL_DS) : "memory"
 		);
 }
 
diff --git a/include/asm-powerpc/kexec.h b/include/asm-powerpc/kexec.h
index bda2f217e6..6a2af2f685 100644
--- a/include/asm-powerpc/kexec.h
+++ b/include/asm-powerpc/kexec.h
@@ -93,7 +93,8 @@ static inline void crash_setup_regs(struct pt_regs *newregs,
 			"mfxer  %0\n"
 			"std    %0, 296(%2)\n"
 			: "=&r" (tmp1), "=&r" (tmp2)
-			: "b" (newregs));
+			: "b" (newregs)
+			: "memory");
 	}
 }
 #else