[PATCH] powerpc: Make the vDSO functions set error code (#2)

The vDSO functions should have the same calling convention as a syscall.
Unfortunately, they currently don't set the cr0.so bit which is used to
indicate an error. This patch makes them clear this bit unconditionally
since all functions currently succeed. The syscall fallback done by some
of them will eventually override this if the syscall fails.

This also changes the symbol version of all vdso exports to make sure
glibc can differenciate between old and fixed calls for existing ones
like __kernel_gettimeofday.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

3 files changed, 8 insertions, 1 deletions

diff --git a/arch/powerpc/kernel/vdso64/cacheflush.S b/arch/powerpc/kernel/vdso64/cacheflush.S
index d4a0ad28d534..cb4ae0a5edd0 100644
--- a/arch/powerpc/kernel/vdso64/cacheflush.S
+++ b/arch/powerpc/kernel/vdso64/cacheflush.S
@@ -35,6 +35,7 @@ V_FUNCTION_BEGIN(__kernel_sync_dicache)
         subf    r8,r6,r4                /* compute length */
         add     r8,r8,r5                /* ensure we get enough */
         srwi.   r8,r8,7                 /* compute line count */
+        crclr   cr0*4+so
         beqlr                           /* nothing to do? */
         mtctr   r8
         mr      r3,r6
@@ -58,6 +59,7 @@ V_FUNCTION_END(__kernel_sync_dicache)
  */
 V_FUNCTION_BEGIN(__kernel_sync_dicache_p5)
   .cfi_startproc
+        crclr   cr0*4+so
         sync
         isync
         li      r3,0
diff --git a/arch/powerpc/kernel/vdso64/datapage.S b/arch/powerpc/kernel/vdso64/datapage.S
index 6393e4137bc7..3b2dd7d0c1eb 100644
--- a/arch/powerpc/kernel/vdso64/datapage.S
+++ b/arch/powerpc/kernel/vdso64/datapage.S
@@ -54,12 +54,12 @@ V_FUNCTION_BEGIN(__kernel_get_syscall_map)
   .cfi_startproc
         mflr    r12
   .cfi_register lr,r12
-
         mr      r4,r3
         bl      V_LOCAL_FUNC(__get_datapage)
         mtlr    r12
         addi    r3,r3,CFG_SYSCALL_MAP64
         cmpli   cr0,r4,0
+        crclr   cr0*4+so
         beqlr
         li      r0,__NR_syscalls
         stw     r0,0(r4)
@@ -80,6 +80,7 @@ V_FUNCTION_BEGIN(__kernel_get_tbfreq)
         bl      V_LOCAL_FUNC(__get_datapage)
         ld      r3,CFG_TB_TICKS_PER_SEC(r3)
         mtlr    r12
+        crclr   cr0*4+so
         blr
   .cfi_endproc
 V_FUNCTION_END(__kernel_get_tbfreq)
diff --git a/arch/powerpc/kernel/vdso64/gettimeofday.S b/arch/powerpc/kernel/vdso64/gettimeofday.S
index 1a89094715cc..ccaeda5136d1 100644
--- a/arch/powerpc/kernel/vdso64/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso64/gettimeofday.S
@@ -52,6 +52,7 @@ V_FUNCTION_BEGIN(__kernel_gettimeofday)
         stw     r4,TZONE_TZ_MINWEST(r10)
         stw     r5,TZONE_TZ_DSTTIME(r10)
 1:      mtlr    r12
+        crclr   cr0*4+so
         li      r3,0                    /* always success */
         blr
   .cfi_endproc
@@ -99,6 +100,7 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
         std     r0,TSPC64_TV_NSEC(r11)  /* store nsec in tp */
 
         mtlr    r12
+        crclr   cr0*4+so
         li      r3,0
         blr
 
@@ -159,6 +161,7 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
         std     r7,TSPC64_TV_NSEC(r11)
 
         mtlr    r12
+        crclr   cr0*4+so
         li      r3,0
         blr
 
@@ -193,6 +196,7 @@ V_FUNCTION_BEGIN(__kernel_clock_getres)
 
         li      r3,0
         cmpli   cr0,r4,0
+        crclr   cr0*4+so
         beqlr
         lis     r5,CLOCK_REALTIME_RES@h
         ori     r5,r5,CLOCK_REALTIME_RES@l