Revert strace hiccups fix.

This reverts commit 40138249c3b7a0762155216b963ec7fd4d09b5b4 and
ffa9009c9828db3f74178e459cfbca6e77ff5dd9.

There are problems with how the flag bytes were rearranged, in
particular we really can't move values down into the lowest
16 bits since those are used for individual state bits.

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

5 files changed, 31 insertions, 30 deletions

diff --git a/arch/sparc/include/asm/ptrace.h b/arch/sparc/include/asm/ptrace.h
index eeed804316b..fd9c3f21cbf 100644
--- a/arch/sparc/include/asm/ptrace.h
+++ b/arch/sparc/include/asm/ptrace.h
@@ -202,7 +202,9 @@ struct global_reg_snapshot {
 };
 extern struct global_reg_snapshot global_reg_snapshot[NR_CPUS];
 
-#define force_successful_syscall_return() set_thread_noerror(1)
+#define force_successful_syscall_return()           \
+do {    current_thread_info()->syscall_noerror = 1; \
+} while (0)
 #define user_mode(regs) (!((regs)->tstate & TSTATE_PRIV))
 #define instruction_pointer(regs) ((regs)->tpc)
 #define instruction_pointer_set(regs, val) ((regs)->tpc = (val))
diff --git a/arch/sparc/include/asm/thread_info_64.h b/arch/sparc/include/asm/thread_info_64.h
index 8511e5fcc97..cfa8c38fb9c 100644
--- a/arch/sparc/include/asm/thread_info_64.h
+++ b/arch/sparc/include/asm/thread_info_64.h
@@ -18,12 +18,10 @@
 #define TI_FLAG_CWP_SHIFT               40
 #define TI_FLAG_BYTE_CURRENT_DS         3
 #define TI_FLAG_CURRENT_DS_SHIFT        32
-#define TI_FLAG_BYTE_NOERROR            4
-#define TI_FLAG_BYTE_NOERROR_SHIFT      24
-#define TI_FLAG_BYTE_FPDEPTH            5
-#define TI_FLAG_FPDEPTH_SHIFT           16
-#define TI_FLAG_BYTE_WSAVED             6
-#define TI_FLAG_WSAVED_SHIFT            8
+#define TI_FLAG_BYTE_FPDEPTH            4
+#define TI_FLAG_FPDEPTH_SHIFT           24
+#define TI_FLAG_BYTE_WSAVED             5
+#define TI_FLAG_WSAVED_SHIFT            16
 
 #include <asm/page.h>
 
@@ -49,7 +47,7 @@ struct thread_info {
         struct exec_domain      *exec_domain;
         int                     preempt_count;  /* 0 => preemptable, <0 => BUG */
         __u8                    new_child;
-        __u8                    __pad;
+        __u8                    syscall_noerror;
         __u16                   cpu;
 
         unsigned long           *utraps;
@@ -79,7 +77,6 @@ struct thread_info {
 #define TI_CURRENT_DS   (TI_FLAGS + TI_FLAG_BYTE_CURRENT_DS)
 #define TI_FPDEPTH      (TI_FLAGS + TI_FLAG_BYTE_FPDEPTH)
 #define TI_WSAVED       (TI_FLAGS + TI_FLAG_BYTE_WSAVED)
-#define TI_SYS_NOERROR  (TI_FLAGS + TI_FLAG_BYTE_NOERROR)
 #define TI_FPSAVED      0x00000010
 #define TI_KSP          0x00000018
 #define TI_FAULT_ADDR   0x00000020
@@ -87,6 +84,7 @@ struct thread_info {
 #define TI_EXEC_DOMAIN  0x00000030
 #define TI_PRE_COUNT    0x00000038
 #define TI_NEW_CHILD    0x0000003c
+#define TI_SYS_NOERROR  0x0000003d
 #define TI_CPU          0x0000003e
 #define TI_UTRAPS       0x00000040
 #define TI_REG_WINDOW   0x00000048
@@ -157,8 +155,6 @@ register struct thread_info *current_thread_info_reg asm("g6");
 #define set_thread_cwp(val)             (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_CWP] = (val))
 #define get_thread_current_ds()         (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_CURRENT_DS])
 #define set_thread_current_ds(val)      (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_CURRENT_DS] = (val))
-#define get_thread_noerror()            (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_NOERROR])
-#define set_thread_noerror(val)         (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_NOERROR] = (val))
 #define get_thread_fpdepth()            (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_FPDEPTH])
 #define set_thread_fpdepth(val)         (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_FPDEPTH] = (val))
 #define get_thread_wsaved()             (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_WSAVED])
diff --git a/arch/sparc/kernel/etrap_64.S b/arch/sparc/kernel/etrap_64.S
index 1276ca2567b..786b185e6e3 100644
--- a/arch/sparc/kernel/etrap_64.S
+++ b/arch/sparc/kernel/etrap_64.S
@@ -92,10 +92,8 @@ etrap_save:	save	%g2, -STACK_BIAS, %sp
                 rdpr    %wstate, %g2
                 wrpr    %g0, 0, %canrestore
                 sll     %g2, 3, %g2
-
-                /* Set TI_SYS_FPDEPTH to 1 and clear TI_SYS_NOERROR.  */
                 mov     1, %l5
-                sth     %l5, [%l6 + TI_SYS_NOERROR]
+                stb     %l5, [%l6 + TI_FPDEPTH]
 
                 wrpr    %g3, 0, %otherwin
                 wrpr    %g2, 0, %wstate
@@ -154,9 +152,7 @@ etrap_save:	save	%g2, -STACK_BIAS, %sp
                 add     %l6, TI_FPSAVED + 1, %l4
                 srl     %l5, 1, %l3
                 add     %l5, 2, %l5
-
-                /* Set TI_SYS_FPDEPTH to %l5 and clear TI_SYS_NOERROR.  */
-                sth     %l5, [%l6 + TI_SYS_NOERROR]
+                stb     %l5, [%l6 + TI_FPDEPTH]
                 ba,pt   %xcc, 2b
                  stb    %g0, [%l4 + %l3]
                 nop
diff --git a/arch/sparc/kernel/syscalls.S b/arch/sparc/kernel/syscalls.S
index b0ac1030642..1d7e274f3f2 100644
--- a/arch/sparc/kernel/syscalls.S
+++ b/arch/sparc/kernel/syscalls.S
@@ -212,19 +212,24 @@ 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,a,pn %l2, 80f
+         stb    %g0, [%g6 + TI_SYS_NOERROR]
+
         cmp     %o0, -ERESTART_RESTARTBLOCK
         bgeu,pn %xcc, 1f
-         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:
+         andcc  %l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT), %l6
+80:
         /* 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
@@ -233,20 +238,20 @@ 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]
-        ba,pt   %xcc, 3b
-         or     %g3, %g2, %g3
+        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]
 
+        b,pt    %xcc, rtrap
+         stx    %l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
 linux_syscall_trace2:
         call    syscall_trace_leave
          add    %sp, PTREGS_OFF, %o0
diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c
index 82af591fe43..fa1f1d375ff 100644
--- a/arch/sparc/kernel/traps_64.c
+++ b/arch/sparc/kernel/traps_64.c
@@ -2547,6 +2547,8 @@ void __init trap_init(void)
                      TI_PRE_COUNT != offsetof(struct thread_info,
                                               preempt_count) ||
                      TI_NEW_CHILD != offsetof(struct thread_info, new_child) ||
+                     TI_SYS_NOERROR != offsetof(struct thread_info,
+                                                syscall_noerror) ||
                      TI_RESTART_BLOCK != offsetof(struct thread_info,
                                                   restart_block) ||
                      TI_KUNA_REGS != offsetof(struct thread_info,