diff options
| author | Michael K. Johnson <johnsonm@rpath.com> | 2009-04-01 20:40:02 +0000 |
|---|---|---|
| committer | Chris Wright <chrisw@sous-sol.org> | 2009-04-27 10:36:52 -0700 |
| commit | 32626208c6548358e28b0857ad030b8a3fa12d86 (patch) | |
| tree | 273414c17f67f0f97bf0035e15936f7af27a378d | |
| parent | 69186bb21b2238901ccabd01f29669cf4e147f71 (diff) | |
x86, setup: mark %esi as clobbered in E820 BIOS call
upstream commit: 01522df346f846906eaf6ca57148641476209909
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
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
| -rw-r--r-- | arch/x86/boot/memory.c | 7 |
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 |