arch/tile: Change struct sigcontext to be more useful

[linux-flexiantxendom0-3.2.10.git] / arch / tile / kernel / signal.c

diff --git a/arch/tile/kernel/signal.c b/arch/tile/kernel/signal.c
index 45b66a3..ce183aa 100644 (file)
--- a/arch/tile/kernel/signal.c
+++ b/arch/tile/kernel/signal.c
@@ -61,13 +61,19 @@ int restore_sigcontext(struct pt_regs *regs,
        /* Always make any pending restarted system calls return -EINTR */
        current_thread_info()->restart_block.fn = do_no_restart_syscall;
 
+       /*
+        * Enforce that sigcontext is like pt_regs, and doesn't mess
+        * up our stack alignment rules.
+        */
+       BUILD_BUG_ON(sizeof(struct sigcontext) != sizeof(struct pt_regs));
+       BUILD_BUG_ON(sizeof(struct sigcontext) % 8 != 0);
+
        for (i = 0; i < sizeof(struct pt_regs)/sizeof(long); ++i)
-               err |= __get_user(((long *)regs)[i],
-                                 &((long __user *)(&sc->regs))[i]);
+               err |= __get_user(regs->regs[i], &sc->gregs[i]);
 
        regs->faultnum = INT_SWINT_1_SIGRETURN;
 
-       err |= __get_user(*pr0, &sc->regs.regs[0]);
+       err |= __get_user(*pr0, &sc->gregs[0]);
        return err;
 }
 
@@ -112,8 +118,7 @@ int setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs)
        int i, err = 0;
 
        for (i = 0; i < sizeof(struct pt_regs)/sizeof(long); ++i)
-               err |= __put_user(((long *)regs)[i],
-                                 &((long __user *)(&sc->regs))[i]);
+               err |= __put_user(regs->regs[i], &sc->gregs[i]);
 
        return err;
 }
@@ -203,19 +208,17 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
         * Set up registers for signal handler.
         * Registers that we don't modify keep the value they had from
         * user-space at the time we took the signal.
+        * We always pass siginfo and mcontext, regardless of SA_SIGINFO,
+        * since some things rely on this (e.g. glibc's debug/segfault.c).
         */
        regs->pc = (unsigned long) ka->sa.sa_handler;
        regs->ex1 = PL_ICS_EX1(USER_PL, 1); /* set crit sec in handler */
        regs->sp = (unsigned long) frame;
        regs->lr = restorer;
        regs->regs[0] = (unsigned long) usig;
-
-       if (ka->sa.sa_flags & SA_SIGINFO) {
-               /* Need extra arguments, so mark to restore caller-saves. */
-               regs->regs[1] = (unsigned long) &frame->info;
-               regs->regs[2] = (unsigned long) &frame->uc;
-               regs->flags |= PT_FLAGS_CALLER_SAVES;
-       }
+       regs->regs[1] = (unsigned long) &frame->info;
+       regs->regs[2] = (unsigned long) &frame->uc;
+       regs->flags |= PT_FLAGS_CALLER_SAVES;
 
        /*
         * Notify any tracer that was single-stepping it.