[PATCH v2 1/7] powerpc: properly negate error in syscall_set_return_value()

["Dmitry V. Levin" <ldv@strace.io>]

Bring syscall_set_return_value() in sync with syscall_get_error(),
and let upcoming ptrace/set_syscall_info selftest pass on powerpc.

This reverts commit 1b1a3702a65c ("powerpc: Don't negate error in
syscall_set_return_value()").

Signed-off-by: Dmitry V. Levin <ldv@strace.io>
---
 arch/powerpc/include/asm/syscall.h | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/syscall.h b/arch/powerpc/include/asm/syscall.h
index 3dd36c5e334a..422d7735ace6 100644
--- a/arch/powerpc/include/asm/syscall.h
+++ b/arch/powerpc/include/asm/syscall.h
@@ -82,7 +82,11 @@ static inline void syscall_set_return_value(struct task_struct *task,
 		 */
 		if (error) {
 			regs->ccr |= 0x10000000L;
-			regs->gpr[3] = error;
+			/*
+			 * In case of an error regs->gpr[3] contains
+			 * a positive ERRORCODE.
+			 */
+			regs->gpr[3] = -error;
 		} else {
 			regs->ccr &= ~0x10000000L;
 			regs->gpr[3] = val;
-- 
ldv