vserver 1.9.5.x5

[linux-2.6.git] / arch / i386 / kernel / signal.c

diff --git a/arch/i386/kernel/signal.c b/arch/i386/kernel/signal.c
index a9b33b1..1e8b41c 100644 (file)
--- a/arch/i386/kernel/signal.c
+++ b/arch/i386/kernel/signal.c
@@ -190,6 +190,12 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *peax
                        if (verify_area(VERIFY_READ, buf, sizeof(*buf)))
                                goto badframe;
                        err |= restore_i387(buf);
+               } else {
+                       struct task_struct *me = current;
+                       if (used_math()) {
+                               clear_fpu(me);
+                               clear_used_math();
+                       }
                }
        }
 
@@ -270,7 +276,6 @@ setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
                 struct pt_regs *regs, unsigned long mask)
 {
        int tmp, err = 0;
-       unsigned long eflags;
 
        tmp = 0;
        __asm__("movl %%gs,%0" : "=r"(tmp): "0"(tmp));
@@ -292,11 +297,7 @@ setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
        err |= __put_user(current->thread.error_code, &sc->err);
        err |= __put_user(regs->eip, &sc->eip);
        err |= __put_user(regs->xcs, (unsigned int __user *)&sc->cs);
-       eflags = regs->eflags;
-       if (current->ptrace & PT_PTRACED) {
-               eflags &= ~TF_MASK;
-       }
-       err |= __put_user(eflags, &sc->eflags);
+       err |= __put_user(regs->eflags, &sc->eflags);
        err |= __put_user(regs->esp, &sc->esp_at_signal);
        err |= __put_user(regs->xss, (unsigned int __user *)&sc->ss);
 
@@ -364,20 +365,20 @@ static void setup_frame(int sig, struct k_sigaction *ka,
                ? current_thread_info()->exec_domain->signal_invmap[sig]
                : sig;
 
-       err |= __put_user(usig, &frame->sig);
+       err = __put_user(usig, &frame->sig);
        if (err)
                goto give_sigsegv;
 
-       err |= setup_sigcontext(&frame->sc, &frame->fpstate, regs, set->sig[0]);
+       err = setup_sigcontext(&frame->sc, &frame->fpstate, regs, set->sig[0]);
        if (err)
                goto give_sigsegv;
 
        if (_NSIG_WORDS > 1) {
-               err |= __copy_to_user(&frame->extramask, &set->sig[1],
+               err = __copy_to_user(&frame->extramask, &set->sig[1],
                                      sizeof(frame->extramask));
+               if (err)
+                       goto give_sigsegv;
        }
-       if (err)
-               goto give_sigsegv;
 
        restorer = &__kernel_sigreturn;
        if (ka->sa.sa_flags & SA_RESTORER)
@@ -412,13 +413,16 @@ static void setup_frame(int sig, struct k_sigaction *ka,
        regs->xes = __USER_DS;
        regs->xss = __USER_DS;
        regs->xcs = __USER_CS;
-       if (regs->eflags & TF_MASK) {
-               if (current->ptrace & PT_PTRACED) {
-                       ptrace_notify(SIGTRAP);
-               } else {
-                       regs->eflags &= ~TF_MASK;
-               }
-       }
+
+       /*
+        * Clear TF when entering the signal handler, but
+        * notify any tracer that was single-stepping it.
+        * The tracer may want to single-step inside the
+        * handler too.
+        */
+       regs->eflags &= ~TF_MASK;
+       if (test_thread_flag(TIF_SINGLESTEP))
+               ptrace_notify(SIGTRAP);
 
 #if DEBUG_SIG
        printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
@@ -502,13 +506,16 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
        regs->xes = __USER_DS;
        regs->xss = __USER_DS;
        regs->xcs = __USER_CS;
-       if (regs->eflags & TF_MASK) {
-               if (current->ptrace & PT_PTRACED) {
-                       ptrace_notify(SIGTRAP);
-               } else {
-                       regs->eflags &= ~TF_MASK;
-               }
-       }
+
+       /*
+        * Clear TF when entering the signal handler, but
+        * notify any tracer that was single-stepping it.
+        * The tracer may want to single-step inside the
+        * handler too.
+        */
+       regs->eflags &= ~TF_MASK;
+       if (test_thread_flag(TIF_SINGLESTEP))
+               ptrace_notify(SIGTRAP);
 
 #if DEBUG_SIG
        printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
@@ -600,7 +607,9 @@ int fastcall do_signal(struct pt_regs *regs, sigset_t *oldset)
                 * have been cleared if the watchpoint triggered
                 * inside the kernel.
                 */
-               __asm__("movl %0,%%db7" : : "r" (current->thread.debugreg[7]));
+               if (unlikely(current->thread.debugreg[7])) {
+                       __asm__("movl %0,%%db7" : : "r" (current->thread.debugreg[7]));
+               }
 
                /* Whee!  Actually deliver the signal.  */
                handle_signal(signr, &info, &ka, oldset, regs);