From 8fbe8fdfbc7576c58c59b605354457cc02076304 Mon Sep 17 00:00:00 2001
From: Tom Musta <tommusta@gmail.com>
Date: Tue, 12 Aug 2014 13:53:41 -0500
Subject: [PATCH] linux-user: clock_nanosleep errno Handling on PPC
The clock_nanosleep syscall is unusual in that it returns positive
numbers in error handling situations, versus returning -1 and setting
errno, or returning a negative errno value. On POWER, the kernel will
set the SO bit of CR0 to indicate failure in a syscall. QEMU has
generic handling to do this for syscalls with standard return values.
Add special case code for clock_nanosleep to handle CR0 properly.
Signed-off-by: Tom Musta <tommusta@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
---
linux-user/syscall.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index ed32f9723f..450f22dcc1 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -9033,6 +9033,14 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
ret = get_errno(clock_nanosleep(arg1, arg2, &ts, arg4 ? &ts : NULL));
if (arg4)
host_to_target_timespec(arg4, &ts);
+
+#if defined(TARGET_PPC)
+ /* clock_nanosleep is odd in that it returns positive errno values.
+ * On PPC, CR0 bit 3 should be set in such a situation. */
+ if (ret) {
+ ((CPUPPCState *)cpu_env)->crf[0] |= 1;
+ }
+#endif
break;
}
#endif
--
2.30.2