kexec, x86: Fix incorrect jump back address if not preserving context

In kexec jump support, jump back address passed to the kexeced
kernel via function calling ABI, that is, the function call
return address is the jump back entry.

Furthermore, jump back entry == 0 should be used to signal that
the jump back or preserve context is not enabled in the original
kernel.

But in the current implementation the stack position used for
function call return address is not cleared context
preservation is disabled. The patch fixes this bug.

Reported-and-tested-by: Yin Kangkai <kangkai.yin@intel.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/1310607277-25029-1-git-send-email-ying.huang@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Huang Ying 2011-07-14 09:34:37 +08:00 committed by Ingo Molnar
parent cf6ace16a3
commit 050438ed5a
2 changed files with 4 additions and 0 deletions

View File

@ -97,6 +97,8 @@ relocate_kernel:
ret
identity_mapped:
/* set return address to 0 if not preserving context */
pushl $0
/* store the start address on the stack */
pushl %edx

View File

@ -100,6 +100,8 @@ relocate_kernel:
ret
identity_mapped:
/* set return address to 0 if not preserving context */
pushq $0
/* store the start address on the stack */
pushq %rdx