path: root/arch/x86/boot/memory.c
diff options
authorMichael K. Johnson <johnsonm@rpath.com>2009-03-27 13:14:41 -0400
committerH. Peter Anvin <hpa@zytor.com>2009-03-28 12:45:39 -0700
commit01522df346f846906eaf6ca57148641476209909 (patch)
tree06fa393052f7f0a033dcc95440788b05c4044ea2 /arch/x86/boot/memory.c
parentc8608d6b58981a58ca4aee8308576666c5f7ab0c (diff)
x86, setup: mark %esi as clobbered in E820 BIOS call
Jordan Hargrave diagnosed a BIOS clobbering %esi in the E820 call. That particular BIOS has been fixed, but there is a possibility that this is responsible for other occasional reports of early boot failure, and it does not hurt to add %esi to the clobbers. -stable candidate patch. Cc: Justin Forbes <jmforbes@linuxtx.org> Signed-off-by: Michael K Johnson <johnsonm@rpath.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: stable@kernel.org
Diffstat (limited to 'arch/x86/boot/memory.c')
1 files changed, 4 insertions, 3 deletions
diff --git a/arch/x86/boot/memory.c b/arch/x86/boot/memory.c
index 8c3c25f35578..a99dbbe77a0c 100644
--- a/arch/x86/boot/memory.c
+++ b/arch/x86/boot/memory.c
@@ -27,13 +27,14 @@ static int detect_memory_e820(void)
do {
size = sizeof(struct e820entry);
- /* Important: %edx is clobbered by some BIOSes,
- so it must be either used for the error output
+ /* Important: %edx and %esi are clobbered by some BIOSes,
+ so they must be either used for the error output
or explicitly marked clobbered. */
asm("int $0x15; setc %0"
: "=d" (err), "+b" (next), "=a" (id), "+c" (size),
"=m" (*desc)
- : "D" (desc), "d" (SMAP), "a" (0xe820));
+ : "D" (desc), "d" (SMAP), "a" (0xe820)
+ : "esi");
/* BIOSes which terminate the chain with CF = 1 as opposed
to %ebx = 0 don't always report the SMAP signature on