ARM: 7470/1: Revert "7443/1: Revert "new way of handling ERESTART_RESTARTBLOCK""
This reverts commit 433e2f307beff8adba241646ce9108544e0c5a03.
Conflicts:
arch/arm/kernel/ptrace.c
Reintroduce the new syscall restart handling in preparation for further
patches from Al Viro.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index dab711e..efd25d6 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -25,6 +25,7 @@
#include <linux/regset.h>
#include <linux/audit.h>
#include <linux/tracehook.h>
+#include <linux/unistd.h>
#include <asm/pgtable.h>
#include <asm/traps.h>
@@ -940,7 +941,12 @@
asmlinkage int syscall_trace_enter(struct pt_regs *regs, int scno)
{
- int ret = ptrace_syscall_trace(regs, scno, PTRACE_SYSCALL_ENTER);
+ int ret;
+
+ if (test_and_clear_thread_flag(TIF_SYSCALL_RESTARTSYS))
+ scno = __NR_restart_syscall - __NR_SYSCALL_BASE;
+
+ ret = ptrace_syscall_trace(regs, scno, PTRACE_SYSCALL_ENTER);
audit_syscall_entry(AUDIT_ARCH_ARM, scno, regs->ARM_r0, regs->ARM_r1,
regs->ARM_r2, regs->ARM_r3);
return ret;
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index 536c5d6..6d3bce5 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -605,12 +605,10 @@
case -ERESTARTNOHAND:
case -ERESTARTSYS:
case -ERESTARTNOINTR:
+ case -ERESTART_RESTARTBLOCK:
regs->ARM_r0 = regs->ARM_ORIG_r0;
regs->ARM_pc = restart_addr;
break;
- case -ERESTART_RESTARTBLOCK:
- regs->ARM_r0 = -EINTR;
- break;
}
}
@@ -626,12 +624,14 @@
* debugger has chosen to restart at a different PC.
*/
if (regs->ARM_pc == restart_addr) {
- if (retval == -ERESTARTNOHAND
+ if (retval == -ERESTARTNOHAND ||
+ retval == -ERESTART_RESTARTBLOCK
|| (retval == -ERESTARTSYS
&& !(ka.sa.sa_flags & SA_RESTART))) {
regs->ARM_r0 = -EINTR;
regs->ARM_pc = continue_addr;
}
+ clear_thread_flag(TIF_SYSCALL_RESTARTSYS);
}
handle_signal(signr, &ka, &info, regs);
@@ -645,29 +645,8 @@
* ignore the restart.
*/
if (retval == -ERESTART_RESTARTBLOCK
- && regs->ARM_pc == continue_addr) {
- if (thumb_mode(regs)) {
- regs->ARM_r7 = __NR_restart_syscall - __NR_SYSCALL_BASE;
- regs->ARM_pc -= 2;
- } else {
-#if defined(CONFIG_AEABI) && !defined(CONFIG_OABI_COMPAT)
- regs->ARM_r7 = __NR_restart_syscall;
- regs->ARM_pc -= 4;
-#else
- u32 __user *usp;
-
- regs->ARM_sp -= 4;
- usp = (u32 __user *)regs->ARM_sp;
-
- if (put_user(regs->ARM_pc, usp) == 0) {
- regs->ARM_pc = KERN_RESTART_CODE;
- } else {
- regs->ARM_sp += 4;
- force_sigsegv(0, current);
- }
-#endif
- }
- }
+ && regs->ARM_pc == restart_addr)
+ set_thread_flag(TIF_SYSCALL_RESTARTSYS);
}
restore_saved_sigmask();