bsd-user/signal.c: Implement rewind_if_in_safe_syscall

Signed-off-by: Kyle Evans <kevans@freebsd.org>
Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

diff --git a/bsd-user/qemu.h b/bsd-user/qemu.h
index 49f01932a53ba07d8f719b7fcf5d0e130b50d955..8ed1bfbca892851e2b9b9792af2bf98742429bde 100644 (file)
--- a/bsd-user/qemu.h
+++ b/bsd-user/qemu.h
@@ -446,4 +446,6 @@ static inline void *lock_user_string(abi_ulong guest_addr)
 
 #include <pthread.h>
 
+#include "user/safe-syscall.h"
+
 #endif /* QEMU_H */

diff --git a/bsd-user/signal.c b/bsd-user/signal.c
index db8cf0a08f1cf974572a50b5e674a698e76aff23..454aef2993e76a1a51fd157a8c51d88ddf41d6e0 100644 (file)
--- a/bsd-user/signal.c
+++ b/bsd-user/signal.c
@@ -48,6 +48,18 @@ int target_to_host_signal(int sig)
     return sig;
 }
 
+/* Adjust the signal context to rewind out of safe-syscall if we're in it */
+static inline void rewind_if_in_safe_syscall(void *puc)
+{
+    ucontext_t *uc = (ucontext_t *)puc;
+    uintptr_t pcreg = host_signal_pc(uc);
+
+    if (pcreg > (uintptr_t)safe_syscall_start
+        && pcreg < (uintptr_t)safe_syscall_end) {
+        host_signal_set_pc(uc, (uintptr_t)safe_syscall_start);
+    }
+}
+
 static bool has_trapno(int tsig)
 {
     return tsig == TARGET_SIGILL ||
@@ -57,7 +69,6 @@ static bool has_trapno(int tsig)
         tsig == TARGET_SIGTRAP;
 }
 
-
 /* Siginfo conversion. */
 
 /*