sparc64: Fix strace hiccups when force_successful_syscall() triggers.

When force_successful_syscall() triggers, the syscall return status
reported the ptrace applications gets garbled.

Fix this by reordering the events and tests in the ret_sys_call path.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 18 deletions

diff --git a/arch/sparc/kernel/syscalls.S b/arch/sparc/kernel/syscalls.S
index ed277e2fdfc8..b0ac10306425 100644
--- a/arch/sparc/kernel/syscalls.S
+++ b/arch/sparc/kernel/syscalls.S
@@ -212,24 +212,19 @@ linux_sparc_syscall:
 3:      stx     %o0, [%sp + PTREGS_OFF + PT_V9_I0]
 ret_sys_call:
         ldx     [%sp + PTREGS_OFF + PT_V9_TSTATE], %g3
-        ldx     [%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
         sra     %o0, 0, %o0
         mov     %ulo(TSTATE_XCARRY | TSTATE_ICARRY), %g2
         sllx    %g2, 32, %g2
 
-        /* Check if force_successful_syscall_return()
-         * was invoked.
-         */
-        ldub    [%g6 + TI_SYS_NOERROR], %l2
-        brnz,pn %l2, 80f
-         nop
-
         cmp     %o0, -ERESTART_RESTARTBLOCK
         bgeu,pn %xcc, 1f
-         andcc  %l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT), %l6
-80:
+         andcc  %l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT), %g0
+        ldx     [%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
+
+2:
         /* System call success, clear Carry condition code. */
         andn    %g3, %g2, %g3
+3:
         stx     %g3, [%sp + PTREGS_OFF + PT_V9_TSTATE]  
         bne,pn  %icc, linux_syscall_trace2
          add    %l1, 0x4, %l2                   ! npc = npc+4
@@ -238,20 +233,20 @@ ret_sys_call:
          stx    %l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
 
 1:
+        /* Check if force_successful_syscall_return()
+         * was invoked.
+         */
+        ldub    [%g6 + TI_SYS_NOERROR], %l2
+        brnz,pn %l2, 2b
+         ldx    [%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
         /* System call failure, set Carry condition code.
          * Also, get abs(errno) to return to the process.
          */
-        andcc   %l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT), %l6  
         sub     %g0, %o0, %o0
-        or      %g3, %g2, %g3
         stx     %o0, [%sp + PTREGS_OFF + PT_V9_I0]
-        stx     %g3, [%sp + PTREGS_OFF + PT_V9_TSTATE]
-        bne,pn  %icc, linux_syscall_trace2
-         add    %l1, 0x4, %l2                   ! npc = npc+4
-        stx     %l1, [%sp + PTREGS_OFF + PT_V9_TPC]
+        ba,pt   %xcc, 3b
+         or     %g3, %g2, %g3
 
-        b,pt    %xcc, rtrap
-         stx    %l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
 linux_syscall_trace2:
         call    syscall_trace_leave
          add    %sp, PTREGS_OFF, %o0