summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorHuang Ying <ying.huang@intel.com>2011-07-14 09:34:37 +0800
committerJonas ABERG <jonas.aberg@stericsson.com>2011-10-28 11:11:08 +0200
commitadb425020a39cc22f5c6df4c6a64776be665479a (patch)
treee47b5a174d6a190c433a55026c14796d03c276d6
parentd4b4c3866ceb8bafc3d89a1dcf83f1f2b621236a (diff)
kexec, x86: Fix incorrect jump back address if not preserving context
commit 050438ed5a05b25cdf287f5691e56a58c2606997 upstream. 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> Link: http://lkml.kernel.org/r/1310607277-25029-1-git-send-email-ying.huang@intel.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Change-Id: I75dc3aab96524ef899a3c40a3e759833d045987e Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/35634 Tested-by: Per VAHLNE <per.xx.vahlne@stericsson.com> Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>
-rw-r--r--arch/x86/kernel/relocate_kernel_32.S2
-rw-r--r--arch/x86/kernel/relocate_kernel_64.S2
2 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/kernel/relocate_kernel_32.S b/arch/x86/kernel/relocate_kernel_32.S
index 41235531b11..36818f8ec2b 100644
--- a/arch/x86/kernel/relocate_kernel_32.S
+++ b/arch/x86/kernel/relocate_kernel_32.S
@@ -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
diff --git a/arch/x86/kernel/relocate_kernel_64.S b/arch/x86/kernel/relocate_kernel_64.S
index 4de8f5b3d47..7a6f3b3be3c 100644
--- a/arch/x86/kernel/relocate_kernel_64.S
+++ b/arch/x86/kernel/relocate_kernel_64.S
@@ -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