Re: [PATCH 2/3] arm64: syscall.h: Add sign extension handling in syscall_get_return_value for compat
On 04/16, He Zhe wrote:
--- a/arch/arm64/include/asm/syscall.h
+++ b/arch/arm64/include/asm/syscall.h
@@ -44,7 +44,12 @@ static inline long syscall_get_error(struct task_struct *task,
static inline long syscall_get_return_value(struct task_struct *task,
struct pt_regs *regs)
{
- return regs->regs[0];
+ long val = regs->regs[0];
+
+ if (is_compat_thread(task_thread_info(task)))
+ val = sign_extend64(val, 31);
+
+ return val;
}
I can't really review these arm-specific patches, but with this change both
syscall_get_error() and is_syscall_success() can use syscall_get_return_value()
to avoid the code duplication.
Oleg.