tcg: Toggle page execution for Apple Silicon

Pages can't be both write and executable at the same time on Apple
Silicon. macOS provides public API to switch write protection [1] for
JIT applications, like TCG.

1. https://developer.apple.com/documentation/apple_silicon/porting_just-in-time_compilers_to_apple_silicon

Tested-by: Alexander Graf <agraf@csgraf.de>
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20210113032806.18220-1-r.bolshakov@yadro.com>
[rth: Inline the qemu_thread_jit_* functions;
 drop the MAP_JIT change for a follow-on patch.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Roman Bolshakov
2021-01-13 06:28:07 +03:00
committed by Richard Henderson
parent 6526919224
commit 653b87eb36
4 changed files with 34 additions and 0 deletions

View File

@ -119,6 +119,10 @@ extern int daemon(int, int);
#include "sysemu/os-posix.h"
#endif
#ifdef __APPLE__
#include <AvailabilityMacros.h>
#endif
#include "glib-compat.h"
#include "qemu/typedefs.h"
@ -682,4 +686,28 @@ char *qemu_get_host_name(Error **errp);
*/
size_t qemu_get_host_physmem(void);
/*
* Toggle write/execute on the pages marked MAP_JIT
* for the current thread.
*/
#if defined(MAC_OS_VERSION_11_0) && \
MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_VERSION_11_0
static inline void qemu_thread_jit_execute(void)
{
if (__builtin_available(macOS 11.0, *)) {
pthread_jit_write_protect_np(true);
}
}
static inline void qemu_thread_jit_write(void)
{
if (__builtin_available(macOS 11.0, *)) {
pthread_jit_write_protect_np(false);
}
}
#else
static inline void qemu_thread_jit_write(void) {}
static inline void qemu_thread_jit_execute(void) {}
#endif
#endif