leds: Fix trigger registration race

[linux-2.6-omap-h63xx.git] / arch / sh / kernel / signal_32.c

diff --git a/arch/sh/kernel/signal_32.c b/arch/sh/kernel/signal_32.c
index 51689d29ad45d331aa7c42b9ca4c301afafabdb6..69d09c0b3498e672057fc92f7a5d740be853ef6b 100644 (file)
--- a/arch/sh/kernel/signal_32.c
+++ b/arch/sh/kernel/signal_32.c
@@ -30,6 +30,7 @@
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
 #include <asm/cacheflush.h>
+#include <asm/syscalls.h>
 #include <asm/fpu.h>
 
 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
@@ -215,6 +216,9 @@ asmlinkage int sys_sigreturn(unsigned long r4, unsigned long r5,
        sigset_t set;
        int r0;
 
+        /* Always make any pending restarted system calls return -EINTR */
+       current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
        if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
                goto badframe;
 
@@ -247,9 +251,11 @@ asmlinkage int sys_rt_sigreturn(unsigned long r4, unsigned long r5,
        struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
        struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs->regs[15];
        sigset_t set;
-       stack_t st;
        int r0;
 
+       /* Always make any pending restarted system calls return -EINTR */
+       current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
        if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
                goto badframe;
 
@@ -265,11 +271,9 @@ asmlinkage int sys_rt_sigreturn(unsigned long r4, unsigned long r5,
        if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
                goto badframe;
 
-       if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st)))
+       if (do_sigaltstack(&frame->uc.uc_stack, NULL,
+                          regs->regs[15]) == -EFAULT)
                goto badframe;
-       /* It is more difficult to avoid calling this function than to
-          call it and ignore errors.  */
-       do_sigaltstack((const stack_t __user *)&st, NULL, (unsigned long)frame);
 
        return r0;
 
@@ -429,7 +433,7 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 
        /* Create the ucontext.  */
        err |= __put_user(0, &frame->uc.uc_flags);
-       err |= __put_user(0, &frame->uc.uc_link);
+       err |= __put_user(NULL, &frame->uc.uc_link);
        err |= __put_user((void *)current->sas_ss_sp,
                          &frame->uc.uc_stack.ss_sp);
        err |= __put_user(sas_ss_flags(regs->regs[15]),
@@ -492,37 +496,43 @@ give_sigsegv:
        return -EFAULT;
 }
 
+static inline void
+handle_syscall_restart(unsigned long save_r0, struct pt_regs *regs,
+                      struct sigaction *sa)
+{
+       /* If we're not from a syscall, bail out */
+       if (regs->tra < 0)
+               return;
+
+       /* check for system call restart.. */
+       switch (regs->regs[0]) {
+               case -ERESTART_RESTARTBLOCK:
+               case -ERESTARTNOHAND:
+               no_system_call_restart:
+                       regs->regs[0] = -EINTR;
+                       regs->sr |= 1;
+                       break;
+
+               case -ERESTARTSYS:
+                       if (!(sa->sa_flags & SA_RESTART))
+                               goto no_system_call_restart;
+               /* fallthrough */
+               case -ERESTARTNOINTR:
+                       regs->regs[0] = save_r0;
+                       regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
+                       break;
+       }
+}
+
 /*
  * OK, we're invoking a handler
  */
-
 static int
 handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
              sigset_t *oldset, struct pt_regs *regs, unsigned int save_r0)
 {
        int ret;
 
-       /* Are we from a system call? */
-       if (regs->tra >= 0) {
-               /* If so, check system call restarting.. */
-               switch (regs->regs[0]) {
-                       case -ERESTART_RESTARTBLOCK:
-                       case -ERESTARTNOHAND:
-                       no_system_call_restart:
-                               regs->regs[0] = -EINTR;
-                               break;
-
-                       case -ERESTARTSYS:
-                               if (!(ka->sa.sa_flags & SA_RESTART))
-                                       goto no_system_call_restart;
-                       /* fallthrough */
-                       case -ERESTARTNOINTR:
-                               regs->regs[0] = save_r0;
-                               regs->pc -= instruction_size(
-                                               ctrl_inw(regs->pc - 4));
-                               break;
-               }
-       }
 
        /* Set up the stack frame */
        if (ka->sa.sa_flags & SA_SIGINFO)
@@ -580,6 +590,9 @@ 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);
+
                /* Whee!  Actually deliver the signal.  */
                if (handle_signal(signr, &ka, &info, oldset,
                                  regs, save_r0) == 0) {