Get rid of the global variable saved_eip as it is only written to.
Jump directly to ret_point instead. No functionality change.
Run-tested.
Signed-off-by: Denys Vlasenko <[email protected]>
CC: Pavel Machek <[email protected]>
CC: Linus Torvalds <[email protected]>
CC: Steven Rostedt <[email protected]>
CC: Ingo Molnar <[email protected]>
CC: Borislav Petkov <[email protected]>
CC: "H. Peter Anvin" <[email protected]>
CC: Andy Lutomirski <[email protected]>
CC: Oleg Nesterov <[email protected]>
CC: Frederic Weisbecker <[email protected]>
CC: Alexei Starovoitov <[email protected]>
CC: Will Drewry <[email protected]>
CC: Kees Cook <[email protected]>
CC: [email protected]
CC: [email protected]
---
All three patches are a resend. They still apply cleanly to mingo/tip.git
arch/x86/kernel/acpi/wakeup_32.S | 10 +---------
1 file changed, 1 insertion(+), 9 deletions(-)
diff --git a/arch/x86/kernel/acpi/wakeup_32.S b/arch/x86/kernel/acpi/wakeup_32.S
index 665c6b7..eef2bd3 100644
--- a/arch/x86/kernel/acpi/wakeup_32.S
+++ b/arch/x86/kernel/acpi/wakeup_32.S
@@ -31,17 +31,11 @@ wakeup_pmode_return:
movl %cs:saved_magic, %eax
cmpl $0x12345678, %eax
- jne bogus_magic
-
- # jump to place where we left off
- movl saved_eip, %eax
- jmp *%eax
-
+ je ret_point
bogus_magic:
jmp bogus_magic
-
save_registers:
sidt saved_idt
sldt saved_ldt
@@ -56,7 +50,6 @@ save_registers:
pushfl
popl saved_context_eflags
- movl $ret_point, saved_eip
ret
@@ -88,7 +81,6 @@ ret_point:
.data
ALIGN
ENTRY(saved_magic) .long 0
-ENTRY(saved_eip) .long 0
# saved registers
saved_idt: .long 0,0
--
1.8.1.4
Th "jmp" deleted by this patch in fact compiles to "jmp to next insn",
since ".p2align 4,,7" happens to not do any alignment -
aligning to 2^4 would require more than 7 bytes of padding:
000000b0 <do_suspend_lowlevel>:
b0: e8 fc ff ff ff call <save_processor_state>
b5: e8 8d ff ff ff call 47 <save_registers>
ba: 6a 03 push $0x3
bc: e8 fc ff ff ff call <x86_acpi_enter_sleep_state>
c1: 83 c4 04 add $0x4,%esp
c4: eb 00 jmp c6 <ret_point> <============ THIS
000000c6 <ret_point>:
c6: e8 c4 ff ff ff call 8f <restore_registers>
Run-tested.
Signed-off-by: Denys Vlasenko <[email protected]>
CC: Pavel Machek <[email protected]>
CC: Linus Torvalds <[email protected]>
CC: Steven Rostedt <[email protected]>
CC: Ingo Molnar <[email protected]>
CC: Borislav Petkov <[email protected]>
CC: "H. Peter Anvin" <[email protected]>
CC: Andy Lutomirski <[email protected]>
CC: Oleg Nesterov <[email protected]>
CC: Frederic Weisbecker <[email protected]>
CC: Alexei Starovoitov <[email protected]>
CC: Will Drewry <[email protected]>
CC: Kees Cook <[email protected]>
CC: [email protected]
CC: [email protected]
---
arch/x86/kernel/acpi/wakeup_32.S | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/arch/x86/kernel/acpi/wakeup_32.S b/arch/x86/kernel/acpi/wakeup_32.S
index eef2bd3..5fec9b0 100644
--- a/arch/x86/kernel/acpi/wakeup_32.S
+++ b/arch/x86/kernel/acpi/wakeup_32.S
@@ -68,11 +68,8 @@ ENTRY(do_suspend_lowlevel)
pushl $3
call x86_acpi_enter_sleep_state
addl $4, %esp
+# If S3 fails, we simply fall through to S3 wakeup code:
-# In case of S3 failure, we'll emerge here. Jump
-# to ret_point to recover
- jmp ret_point
- .p2align 4,,7
ret_point:
call restore_registers
call restore_processor_state
--
1.8.1.4
This change simply block-moves bodies of "save_registers"
and "restore_registers" routines into their callers.
Well, almost. In save_registers, we were saving %esp+4
to saved_context_esp, because we were in a subroutine,
there was one additional word (return address) on stack.
Now it is gone, and we are saving %esp to saved_context_esp.
(The patch looks more confusing than the change really is.)
Run-tested.
Signed-off-by: Denys Vlasenko <[email protected]>
CC: Pavel Machek <[email protected]>
CC: Linus Torvalds <[email protected]>
CC: Steven Rostedt <[email protected]>
CC: Ingo Molnar <[email protected]>
CC: Borislav Petkov <[email protected]>
CC: "H. Peter Anvin" <[email protected]>
CC: Andy Lutomirski <[email protected]>
CC: Oleg Nesterov <[email protected]>
CC: Frederic Weisbecker <[email protected]>
CC: Alexei Starovoitov <[email protected]>
CC: Will Drewry <[email protected]>
CC: Kees Cook <[email protected]>
CC: [email protected]
CC: [email protected]
---
arch/x86/kernel/acpi/wakeup_32.S | 27 +++++++++------------------
1 file changed, 9 insertions(+), 18 deletions(-)
diff --git a/arch/x86/kernel/acpi/wakeup_32.S b/arch/x86/kernel/acpi/wakeup_32.S
index 5fec9b0..b8ab4d3 100644
--- a/arch/x86/kernel/acpi/wakeup_32.S
+++ b/arch/x86/kernel/acpi/wakeup_32.S
@@ -36,13 +36,13 @@ bogus_magic:
jmp bogus_magic
-save_registers:
+ENTRY(do_suspend_lowlevel)
+ call save_processor_state
+
sidt saved_idt
sldt saved_ldt
str saved_tss
-
- leal 4(%esp), %eax
- movl %eax, saved_context_esp
+ movl %esp, saved_context_esp
movl %ebx, saved_context_ebx
movl %ebp, saved_context_ebp
movl %esi, saved_context_esi
@@ -50,28 +50,19 @@ save_registers:
pushfl
popl saved_context_eflags
- ret
-
+ pushl $3
+ call x86_acpi_enter_sleep_state
+ addl $4, %esp
+# If S3 fails, we simply fall through to S3 wakeup code:
-restore_registers:
+ret_point:
movl saved_context_ebp, %ebp
movl saved_context_ebx, %ebx
movl saved_context_esi, %esi
movl saved_context_edi, %edi
pushl saved_context_eflags
popfl
- ret
-
-ENTRY(do_suspend_lowlevel)
- call save_processor_state
- call save_registers
- pushl $3
- call x86_acpi_enter_sleep_state
- addl $4, %esp
-# If S3 fails, we simply fall through to S3 wakeup code:
-ret_point:
- call restore_registers
call restore_processor_state
ret
--
1.8.1.4