parisc: Fix ptraced 64-bit applications to call 64-bit syscalls

Fix the strace code path to call 64-bit syscalls in case we are
executing by a 64-bit application.

Signed-off-by: Helge Deller <deller@gmx.de>

1 files changed, 18 insertions, 4 deletions

diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S
index 5f7e57fcaeef..be451766e9d0 100644
--- a/arch/parisc/kernel/syscall.S
+++ b/arch/parisc/kernel/syscall.S
@@ -227,8 +227,7 @@ linux_gateway_entry:
         or,=    %r2,%r2,%r2
         ldo     R%sys_call_table64(%r1), %r19
 #else
-        ldil    L%sys_call_table, %r1
-        ldo     R%sys_call_table(%r1), %r19
+        load32  sys_call_table, %r19
 #endif  
         comiclr,>>      __NR_Linux_syscalls, %r20, %r0
         b,n     .Lsyscall_nosys
@@ -331,8 +330,6 @@ tracesys_next:
          *  task->thread.regs.gr[20] above.
          */
         copy    %ret0,%r20
-        ldil    L%sys_call_table,%r1
-        ldo     R%sys_call_table(%r1), %r19
 
         ldo     -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1      /* get task ptr */
         LDREG   TI_TASK(%r1), %r1
@@ -354,6 +351,23 @@ tracesys_next:
         comiclr,>>      __NR_Linux_syscalls, %r20, %r0
         b,n     .Ltracesys_nosys
 
+        /* Note!  We cannot use the syscall table that is mapped
+        nearby since the gateway page is mapped execute-only. */
+
+#ifdef CONFIG_64BIT
+        LDREG   TASK_PT_GR30(%r1), %r19         /* get users sp back */
+        extrd,u %r19,63,1,%r2                   /* W hidden in bottom bit */
+
+        ldil    L%sys_call_table, %r1
+        or,=    %r2,%r2,%r2
+        addil   L%(sys_call_table64-sys_call_table), %r1
+        ldo     R%sys_call_table(%r1), %r19
+        or,=    %r2,%r2,%r2
+        ldo     R%sys_call_table64(%r1), %r19
+#else
+        load32  sys_call_table, %r19
+#endif
+
         LDREGX  %r20(%r19), %r19
 
         /* If this is a sys_rt_sigreturn call, and the signal was received