From: 黄涛 <huangtao@rock-chips.com>
Date: Sat, 30 Jul 2011 15:09:53 +0000 (+0800)
Subject: Revert "[ARM] Add code to prevent system calls from being restarted muliple times... 
X-Git-Tag: firefly_0821_release~9840
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6c7d3683e64f591cfe22e252f5fa24d497a4b8ae;p=firefly-linux-kernel-4.4.55.git

Revert "[ARM] Add code to prevent system calls from being restarted muliple times before returning from the kernel."

This reverts commit 85d747b476df558eb36fd9966125a08f02ab5d12.
---

diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index 29a905bf747d..e7714f367eb8 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -517,14 +517,6 @@ setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info,
 
 static inline void setup_syscall_restart(struct pt_regs *regs)
 {
-	if (regs->ARM_ORIG_r0 == -ERESTARTNOHAND ||
-	    regs->ARM_ORIG_r0 == -ERESTARTSYS ||
-	    regs->ARM_ORIG_r0 == -ERESTARTNOINTR ||
-	    regs->ARM_ORIG_r0 == -ERESTART_RESTARTBLOCK) {
-		/* the syscall cannot be safely restarted, return -EINTR instead */
-		regs->ARM_r0 = -EINTR;
-		return;
-	}
 	regs->ARM_r0 = regs->ARM_ORIG_r0;
 	regs->ARM_pc -= thumb_mode(regs) ? 2 : 4;
 }
@@ -657,7 +649,6 @@ static void do_signal(struct pt_regs *regs, int syscall)
 	 */
 	if (syscall) {
 		if (regs->ARM_r0 == -ERESTART_RESTARTBLOCK) {
-			regs->ARM_r0 = -EAGAIN; /* prevent multiple restarts */
 			if (thumb_mode(regs)) {
 				regs->ARM_r7 = __NR_restart_syscall - __NR_SYSCALL_BASE;
 				regs->ARM_pc -= 2;