[PATCH] m68k, exec: remove redundant set_fs(USER_DS)

From: Mathias Krause
Date: Fri Jun 10 2011 - 09:10:03 EST


The address limit is already set in flush_old_exec() so those calls to
set_fs(USER_DS) are redundant.

Signed-off-by: Mathias Krause <minipli@xxxxxxxxxxxxxx>
Cc: Greg Ungerer <gerg@xxxxxxxxxxx>
---

Note: I'm not sure about the assignment to current->thread.fs in
flush_thread() -- shouldn't this be done in set_fs() itself?

arch/m68k/include/asm/processor.h | 4 ----
arch/m68k/kernel/process_mm.c | 2 +-
arch/m68k/kernel/process_no.c | 2 +-
3 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/m68k/include/asm/processor.h b/arch/m68k/include/asm/processor.h
index f111b02..d8ef53a 100644
--- a/arch/m68k/include/asm/processor.h
+++ b/arch/m68k/include/asm/processor.h
@@ -105,9 +105,6 @@ struct thread_struct {
static inline void start_thread(struct pt_regs * regs, unsigned long pc,
unsigned long usp)
{
- /* reads from user space */
- set_fs(USER_DS);
-
regs->pc = pc;
regs->sr &= ~0x2000;
wrusp(usp);
@@ -129,7 +126,6 @@ extern int handle_kernel_fault(struct pt_regs *regs);

#define start_thread(_regs, _pc, _usp) \
do { \
- set_fs(USER_DS); /* reads from user space */ \
(_regs)->pc = (_pc); \
((struct switch_stack *)(_regs))[-1].a6 = 0; \
reformat(_regs); \
diff --git a/arch/m68k/kernel/process_mm.c b/arch/m68k/kernel/process_mm.c
index c2a1fc2..1bc223a 100644
--- a/arch/m68k/kernel/process_mm.c
+++ b/arch/m68k/kernel/process_mm.c
@@ -185,7 +185,7 @@ EXPORT_SYMBOL(kernel_thread);
void flush_thread(void)
{
unsigned long zero = 0;
- set_fs(USER_DS);
+
current->thread.fs = __USER_DS;
if (!FPU_IS_EMU)
asm volatile (".chip 68k/68881\n\t"
diff --git a/arch/m68k/kernel/process_no.c b/arch/m68k/kernel/process_no.c
index 9b86ad1..69c1803 100644
--- a/arch/m68k/kernel/process_no.c
+++ b/arch/m68k/kernel/process_no.c
@@ -158,7 +158,7 @@ void flush_thread(void)
#ifdef CONFIG_FPU
unsigned long zero = 0;
#endif
- set_fs(USER_DS);
+
current->thread.fs = __USER_DS;
#ifdef CONFIG_FPU
if (!FPU_IS_EMU)
--
1.5.6.5

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