The patch titled
     ACPI: preserve the ebx value in acpi_copy_wakeup_routine
has been added to the -mm tree.  Its filename is
     acpi-preserve-the-ebx-value-in-acpi_copy_wakeup_routine.patch

*** Remember to use Documentation/SubmitChecklist when testing your code ***

See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this

------------------------------------------------------
Subject: ACPI: preserve the ebx value in acpi_copy_wakeup_routine
From: Tian Kevin <[EMAIL PROTECTED]>

Register %ebx serves as the "global offset table base register" for
position-independent code.  For absolute code, %ebx serves as a local
register and has no specified role in the function calling sequence.  In
either case, a function must preserve the register value for the caller.

acpi_copy_wakeup_routine overrides %ebx without saving it, this may corrupt
the called data.

Kevin found that most time the value of Sx is saved in %esi, however
sometimes compiler also uses %ebx.  When this happens, suspends fails since
sleep value in ebx is changed by acpi_copy_wakeup_routine.

The same funtion in X86_64 doesn't have this problem.

Signed-off-by: Zhang Rui <[EMAIL PROTECTED]>
Looks-okay-to: Pavel Machek <[EMAIL PROTECTED]>
Signed-off-by: Rafael J. Wysocki <[EMAIL PROTECTED]>
Cc: Len Brown <[EMAIL PROTECTED]>
Cc: Andi Kleen <[EMAIL PROTECTED]>
Cc: Andrew Morton <[EMAIL PROTECTED]>
Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
---

 arch/i386/kernel/acpi/wakeup.S |    2 ++
 1 files changed, 2 insertions(+)

diff -puN 
arch/i386/kernel/acpi/wakeup.S~acpi-preserve-the-ebx-value-in-acpi_copy_wakeup_routine
 arch/i386/kernel/acpi/wakeup.S
--- 
a/arch/i386/kernel/acpi/wakeup.S~acpi-preserve-the-ebx-value-in-acpi_copy_wakeup_routine
+++ a/arch/i386/kernel/acpi/wakeup.S
@@ -230,6 +230,7 @@ bogus_magic:
 #
 ENTRY(acpi_copy_wakeup_routine)
 
+       pushl   %ebx
        sgdt    saved_gdt
        sidt    saved_idt
        sldt    saved_ldt
@@ -263,6 +264,7 @@ ENTRY(acpi_copy_wakeup_routine)
        movl    %edx, video_flags - wakeup_start (%eax)
        movl    $0x12345678, real_magic - wakeup_start (%eax)
        movl    $0x12345678, saved_magic
+       popl    %ebx
        ret
 
 save_registers:
_

Patches currently in -mm which might be from [EMAIL PROTECTED] are

acpi-preserve-the-ebx-value-in-acpi_copy_wakeup_routine.patch

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