microblaze: switch to generic sigaltstack

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2 files changed, 3 insertions, 15 deletions

diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index ba3b7c8c04b8..5e30d75c74ed 100644
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -27,6 +27,7 @@ config MICROBLAZE
         select GENERIC_CLOCKEVENTS
         select MODULES_USE_ELF_RELA
         select CLONE_BACKWARDS
+        select GENERIC_SIGALTSTACK
 
 config SWAP
         def_bool n
diff --git a/arch/microblaze/kernel/signal.c b/arch/microblaze/kernel/signal.c
index ac3d0a0f4814..dfd61e2f1189 100644
--- a/arch/microblaze/kernel/signal.c
+++ b/arch/microblaze/kernel/signal.c
@@ -41,13 +41,6 @@
 #include <asm/cacheflush.h>
 #include <asm/syscalls.h>
 
-asmlinkage long
-sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
-                struct pt_regs *regs)
-{
-        return do_sigaltstack(uss, uoss, regs->r1);
-}
-
 /*
  * Do a signal return; undo the signal stack.
  */
@@ -109,9 +102,7 @@ asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
         if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &rval))
                 goto badframe;
 
-        /* It is more difficult to avoid calling this function than to
-         call it and ignore errors. */
-        if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->r1) == -EFAULT)
+        if (restore_altstack(&frame->uc.uc_stack))
                 goto badframe;
 
         return rval;
@@ -194,11 +185,7 @@ 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(NULL, &frame->uc.uc_link);
-        err |= __put_user((void __user *)current->sas_ss_sp,
-                        &frame->uc.uc_stack.ss_sp);
-        err |= __put_user(sas_ss_flags(regs->r1),
-                        &frame->uc.uc_stack.ss_flags);
-        err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+        err |= __save_altstack(&frame->uc.uc_stack, regs->r1);
         err |= setup_sigcontext(&frame->uc.uc_mcontext,
                         regs, set->sig[0]);
         err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));