From: Josh Poimboeuf <[EMAIL PROTECTED]>
The powerpc 32-bit and 64-bit kernel_thread functions don't properly
propagate errors being returned by the clone syscall. (In the case of
error, the syscall exit code returns a positive errno in r3 and sets
the CR0[SO] bit.)
This patch fixes that by negating r3 if CR0[SO] is set after the syscall.
Signed-off-by: Josh Poimboeuf <[EMAIL PROTECTED]>
Signed-off-by: Josh Boyer <[EMAIL PROTECTED]>
---
arch/powerpc/kernel/misc_32.S | 8 +++++---
arch/powerpc/kernel/misc_64.S | 8 +++++---
2 files changed, 10 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index 7a6dfbc..1fe9f62 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -846,8 +846,10 @@ _GLOBAL(kernel_thread)
li r4,0 /* new sp (unused) */
li r0,__NR_clone
sc
- cmpwi 0,r3,0 /* parent or child? */
- bne 1f /* return if parent */
+ bns+ 1f /* did system call indicate error? */
+ neg r3,r3 /* if so, make return code negative */
+1: cmpwi 0,r3,0 /* parent or child? */
+ bne 2f /* return if parent */
li r0,0 /* make top-level stack frame */
stwu r0,-16(r1)
mtlr r30 /* fn addr in lr */
@@ -857,7 +859,7 @@ _GLOBAL(kernel_thread)
li r0,__NR_exit /* exit if function returns */
li r3,0
sc
-1: lwz r30,8(r1)
+2: lwz r30,8(r1)
lwz r31,12(r1)
addi r1,r1,16
blr
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index 4dd70cf..3053fe5 100644
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -426,8 +426,10 @@ _GLOBAL(kernel_thread)
li r4,0 /* new sp (unused) */
li r0,__NR_clone
sc
- cmpdi 0,r3,0 /* parent or child? */
- bne 1f /* return if parent */
+ bns+ 1f /* did system call indicate error? */
+ neg r3,r3 /* if so, make return code negative */
+1: cmpdi 0,r3,0 /* parent or child? */
+ bne 2f /* return if parent */
li r0,0
stdu r0,-STACK_FRAME_OVERHEAD(r1)
ld r2,8(r29)
@@ -438,7 +440,7 @@ _GLOBAL(kernel_thread)
li r0,__NR_exit /* exit after child exits */
li r3,0
sc
-1: addi r1,r1,STACK_FRAME_OVERHEAD
+2: addi r1,r1,STACK_FRAME_OVERHEAD
ld r29,-24(r1)
ld r30,-16(r1)
blr
--
1.5.5.1
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