Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal

Pull signal handling cleanups from Al Viro:
 "sigaltstack infrastructure + conversion for x86, alpha and um,
  COMPAT_SYSCALL_DEFINE infrastructure.

  Note that there are several conflicts between "unify
  SS_ONSTACK/SS_DISABLE definitions" and UAPI patches in mainline;
  resolution is trivial - just remove definitions of SS_ONSTACK and
  SS_DISABLED from arch/*/uapi/asm/signal.h; they are all identical and
  include/uapi/linux/signal.h contains the unified variant."

Fixed up conflicts as per Al.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  alpha: switch to generic sigaltstack
  new helpers: __save_altstack/__compat_save_altstack, switch x86 and um to those
  generic compat_sys_sigaltstack()
  introduce generic sys_sigaltstack(), switch x86 and um to it
  new helper: compat_user_stack_pointer()
  new helper: restore_altstack()
  unify SS_ONSTACK/SS_DISABLE definitions
  new helper: current_user_stack_pointer()
  missing user_stack_pointer() instances
  Bury the conditionals from kernel_thread/kernel_execve series
  COMPAT_SYSCALL_DEFINE: infrastructure

3 files changed, 3 insertions, 5 deletions

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index f9ccff915918..9c829b008261 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -8,8 +8,6 @@ config ARM64
         select GENERIC_IOMAP
         select GENERIC_IRQ_PROBE
         select GENERIC_IRQ_SHOW
-        select GENERIC_KERNEL_EXECVE
-        select GENERIC_KERNEL_THREAD
         select GENERIC_SMP_IDLE_THREAD
         select GENERIC_TIME_VSYSCALL
         select HARDIRQS_SW_RESEND
diff --git a/arch/arm64/include/asm/compat.h b/arch/arm64/include/asm/compat.h
index 37e610dc084e..d9ec40217a27 100644
--- a/arch/arm64/include/asm/compat.h
+++ b/arch/arm64/include/asm/compat.h
@@ -209,10 +209,11 @@ static inline compat_uptr_t ptr_to_compat(void __user *uptr)
         return (u32)(unsigned long)uptr;
 }
 
+#define compat_user_stack_pointer() (current_pt_regs()->compat_sp)
+
 static inline void __user *arch_compat_alloc_user_space(long len)
 {
-        struct pt_regs *regs = task_pt_regs(current);
-        return (void __user *)regs->compat_sp - len;
+        return (void __user *)compat_user_stack_pointer() - len;
 }
 
 struct compat_ipc64_perm {
diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h
index 76fb7dd3350a..744087fb521c 100644
--- a/arch/arm64/include/asm/unistd.h
+++ b/arch/arm64/include/asm/unistd.h
@@ -28,6 +28,5 @@
 #define __ARCH_WANT_SYS_FORK
 #define __ARCH_WANT_SYS_VFORK
 #endif
-#define __ARCH_WANT_SYS_EXECVE
 #define __ARCH_WANT_SYS_CLONE
 #include <uapi/asm/unistd.h>