[PATCH 2/2] x86_64: Fix S3 fail path

From: Rafael J. Wysocki
Date: Sun Feb 15 2009 - 16:47:40 EST


From: Jiri Slaby <jirislaby@xxxxxxxxx>

As acpi_enter_sleep_state can fail, take this into account in
do_suspend_lowlevel and don't return to the do_suspend_lowlevel's
caller. This would break (currently) fpu status and preempt count.

Technically, this means use `call' instead of `jmp' and `jmp' to
the `resume_point' after the `call' (i.e. if
acpi_enter_sleep_state returns=fails). `resume_point' will handle
the restore of fpu and preempt count gracefully.

Signed-off-by: Jiri Slaby <jirislaby@xxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx>
---
arch/x86/kernel/acpi/wakeup_64.S | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

Index: linux-2.6/arch/x86/kernel/acpi/wakeup_64.S
===================================================================
--- linux-2.6.orig/arch/x86/kernel/acpi/wakeup_64.S
+++ linux-2.6/arch/x86/kernel/acpi/wakeup_64.S
@@ -73,7 +73,9 @@ ENTRY(do_suspend_lowlevel)
addq $8, %rsp
movl $3, %edi
xorl %eax, %eax
- jmp acpi_enter_sleep_state
+ call acpi_enter_sleep_state
+ /* in case something went wrong, restore the machine status and go on */
+ jmp resume_point

.align 4
resume_point:
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/