* Re: ERESTART* seen by userland
2009-01-16 23:40 ERESTART* seen by userland Kaz Kojima
2009-01-20 3:22 ` Paul Mundt
@ 2009-01-20 4:43 ` Kaz Kojima
2009-01-27 7:27 ` Paul Mundt
2009-01-30 23:40 ` Kaz Kojima
3 siblings, 0 replies; 5+ messages in thread
From: Kaz Kojima @ 2009-01-20 4:43 UTC (permalink / raw)
To: linux-sh
Paul Mundt <lethal@linux-sh.org> wrote:
>> It seems that some syscalls return with ERESTART* errno when
>> they should return EINTR in the recent SH kernels.
>> Has anybody experienced this?
>>
> I haven't hit this personally, but the only logical explanation I can
> think of for this is the T-bit setting in the syscall restart code. I
> suppose I will have to find another bit to use. Can you confirm if
> getting rid of regs->sr T-bit manipulation makes this go away?
I've confirmed that my testcases are fixed with removing the if line
just before handle_syscall_restart call in do_signal:
--- GIT/linux-2.6/arch/sh/kernel/signal_32.c 2008-12-30 09:31:12.000000000 +0900
+++ linux-2.6.29-rc1/arch/sh/kernel/signal_32.c 2009-01-20 12:48:40.000000000 +0900
@@ -589,8 +589,7 @@ static void do_signal(struct pt_regs *re
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
if (signr > 0) {
- if (regs->sr & 1)
- handle_syscall_restart(save_r0, regs, &ka.sa);
+ handle_syscall_restart(save_r0, regs, &ka.sa);
/* Whee! Actually deliver the signal. */
if (handle_signal(signr, &ka, &info, oldset,
Regards,
kaz
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: ERESTART* seen by userland
2009-01-16 23:40 ERESTART* seen by userland Kaz Kojima
2009-01-20 3:22 ` Paul Mundt
2009-01-20 4:43 ` Kaz Kojima
@ 2009-01-27 7:27 ` Paul Mundt
2009-01-30 23:40 ` Kaz Kojima
3 siblings, 0 replies; 5+ messages in thread
From: Paul Mundt @ 2009-01-27 7:27 UTC (permalink / raw)
To: linux-sh
On Tue, Jan 20, 2009 at 01:43:50PM +0900, Kaz Kojima wrote:
> Paul Mundt <lethal@linux-sh.org> wrote:
> >> It seems that some syscalls return with ERESTART* errno when
> >> they should return EINTR in the recent SH kernels.
> >> Has anybody experienced this?
> >>
> > I haven't hit this personally, but the only logical explanation I can
> > think of for this is the T-bit setting in the syscall restart code. I
> > suppose I will have to find another bit to use. Can you confirm if
> > getting rid of regs->sr T-bit manipulation makes this go away?
>
> I've confirmed that my testcases are fixed with removing the if line
> just before handle_syscall_restart call in do_signal:
>
> --- GIT/linux-2.6/arch/sh/kernel/signal_32.c 2008-12-30 09:31:12.000000000 +0900
> +++ linux-2.6.29-rc1/arch/sh/kernel/signal_32.c 2009-01-20 12:48:40.000000000 +0900
> @@ -589,8 +589,7 @@ static void do_signal(struct pt_regs *re
>
> signr = get_signal_to_deliver(&info, &ka, regs, NULL);
> if (signr > 0) {
> - if (regs->sr & 1)
> - handle_syscall_restart(save_r0, regs, &ka.sa);
> + handle_syscall_restart(save_r0, regs, &ka.sa);
>
> /* Whee! Actually deliver the signal. */
> if (handle_signal(signr, &ka, &info, oldset,
>
This should fix it up:
---
arch/sh/include/asm/syscall_32.h | 22 +++-------------------
arch/sh/include/asm/syscall_64.h | 22 +++-------------------
arch/sh/kernel/signal_32.c | 4 +---
arch/sh/kernel/signal_64.c | 4 +---
4 files changed, 8 insertions(+), 44 deletions(-)
diff --git a/arch/sh/include/asm/syscall_32.h b/arch/sh/include/asm/syscall_32.h
index 05a868a..5bc3468 100644
--- a/arch/sh/include/asm/syscall_32.h
+++ b/arch/sh/include/asm/syscall_32.h
@@ -21,23 +21,10 @@ static inline void syscall_rollback(struct task_struct *task,
*/
}
-static inline bool syscall_has_error(struct pt_regs *regs)
-{
- return (regs->sr & 0x1) ? true : false;
-}
-static inline void syscall_set_error(struct pt_regs *regs)
-{
- regs->sr |= 0x1;
-}
-static inline void syscall_clear_error(struct pt_regs *regs)
-{
- regs->sr &= ~0x1;
-}
-
static inline long syscall_get_error(struct task_struct *task,
struct pt_regs *regs)
{
- return syscall_has_error(regs) ? regs->regs[0] : 0;
+ return IS_ERR_VALUE(regs->regs[0]) ? regs->regs[0] : 0;
}
static inline long syscall_get_return_value(struct task_struct *task,
@@ -50,13 +37,10 @@ static inline void syscall_set_return_value(struct task_struct *task,
struct pt_regs *regs,
int error, long val)
{
- if (error) {
- syscall_set_error(regs);
+ if (error)
regs->regs[0] = -error;
- } else {
- syscall_clear_error(regs);
+ else
regs->regs[0] = val;
- }
}
static inline void syscall_get_arguments(struct task_struct *task,
diff --git a/arch/sh/include/asm/syscall_64.h b/arch/sh/include/asm/syscall_64.h
index e1143b9..c3561ca 100644
--- a/arch/sh/include/asm/syscall_64.h
+++ b/arch/sh/include/asm/syscall_64.h
@@ -21,23 +21,10 @@ static inline void syscall_rollback(struct task_struct *task,
*/
}
-static inline bool syscall_has_error(struct pt_regs *regs)
-{
- return (regs->sr & 0x1) ? true : false;
-}
-static inline void syscall_set_error(struct pt_regs *regs)
-{
- regs->sr |= 0x1;
-}
-static inline void syscall_clear_error(struct pt_regs *regs)
-{
- regs->sr &= ~0x1;
-}
-
static inline long syscall_get_error(struct task_struct *task,
struct pt_regs *regs)
{
- return syscall_has_error(regs) ? regs->regs[9] : 0;
+ return IS_ERR_VALUE(regs->regs[9]) ? regs->regs[9] : 0;
}
static inline long syscall_get_return_value(struct task_struct *task,
@@ -50,13 +37,10 @@ static inline void syscall_set_return_value(struct task_struct *task,
struct pt_regs *regs,
int error, long val)
{
- if (error) {
- syscall_set_error(regs);
+ if (error)
regs->regs[9] = -error;
- } else {
- syscall_clear_error(regs);
+ else
regs->regs[9] = val;
- }
}
static inline void syscall_get_arguments(struct task_struct *task,
diff --git a/arch/sh/kernel/signal_32.c b/arch/sh/kernel/signal_32.c
index 77c21bd..17784e1 100644
--- a/arch/sh/kernel/signal_32.c
+++ b/arch/sh/kernel/signal_32.c
@@ -510,7 +510,6 @@ handle_syscall_restart(unsigned long save_r0, struct pt_regs *regs,
case -ERESTARTNOHAND:
no_system_call_restart:
regs->regs[0] = -EINTR;
- regs->sr |= 1;
break;
case -ERESTARTSYS:
@@ -589,8 +588,7 @@ static void do_signal(struct pt_regs *regs, unsigned int save_r0)
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
if (signr > 0) {
- if (regs->sr & 1)
- handle_syscall_restart(save_r0, regs, &ka.sa);
+ handle_syscall_restart(save_r0, regs, &ka.sa);
/* Whee! Actually deliver the signal. */
if (handle_signal(signr, &ka, &info, oldset,
diff --git a/arch/sh/kernel/signal_64.c b/arch/sh/kernel/signal_64.c
index b22fdfa..0663a0e 100644
--- a/arch/sh/kernel/signal_64.c
+++ b/arch/sh/kernel/signal_64.c
@@ -60,7 +60,6 @@ handle_syscall_restart(struct pt_regs *regs, struct sigaction *sa)
case -ERESTARTNOHAND:
no_system_call_restart:
regs->regs[REG_RET] = -EINTR;
- regs->sr |= 1;
break;
case -ERESTARTSYS:
@@ -109,8 +108,7 @@ static int do_signal(struct pt_regs *regs, sigset_t *oldset)
signr = get_signal_to_deliver(&info, &ka, regs, 0);
if (signr > 0) {
- if (regs->sr & 1)
- handle_syscall_restart(regs, &ka.sa);
+ handle_syscall_restart(regs, &ka.sa);
/* Whee! Actually deliver the signal. */
if (handle_signal(signr, &info, &ka, oldset, regs) = 0) {
^ permalink raw reply related [flat|nested] 5+ messages in thread