target/arm: Restrict semi-hosting to TCG

Per Peter Maydell:

  Semihosting hooks either SVC or HLT instructions, and inside KVM
  both of those go to EL1, ie to the guest, and can't be trapped to
  KVM.

Let check_for_semihosting() return False when not running on TCG.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190701194942.10092-3-philmd@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Philippe Mathieu-Daudé 2019-07-04 17:14:43 +01:00 committed by Peter Maydell
parent 9dd5cca424
commit 91f78c58da
3 changed files with 15 additions and 2 deletions

View File

@ -1,4 +1,4 @@
obj-y += arm-semi.o
obj-$(CONFIG_TCG) += arm-semi.o
obj-y += helper.o vfp_helper.o
obj-y += cpu.o gdbstub.o
obj-$(TARGET_AARCH64) += cpu64.o gdbstub64.o

View File

@ -964,7 +964,14 @@ static inline void aarch64_sve_change_el(CPUARMState *env, int o,
{ }
#endif
#if !defined(CONFIG_TCG)
static inline target_ulong do_arm_semihosting(CPUARMState *env)
{
g_assert_not_reached();
}
#else
target_ulong do_arm_semihosting(CPUARMState *env);
#endif
void aarch64_sync_32_to_64(CPUARMState *env);
void aarch64_sync_64_to_32(CPUARMState *env);

View File

@ -20,7 +20,6 @@
#include "qemu/qemu-print.h"
#include "exec/exec-all.h"
#include "exec/cpu_ldst.h"
#include "arm_ldst.h"
#include <zlib.h> /* For crc32 */
#include "hw/semihosting/semihost.h"
#include "sysemu/cpus.h"
@ -29,6 +28,9 @@
#include "qapi/qapi-commands-machine-target.h"
#include "qapi/error.h"
#include "qemu/guest-random.h"
#ifdef CONFIG_TCG
#include "arm_ldst.h"
#endif
#define ARM_CPU_FREQ 1000000000 /* FIXME: 1 GHz, should be configurable */
@ -10399,6 +10401,7 @@ static void arm_cpu_do_interrupt_aarch64(CPUState *cs)
static inline bool check_for_semihosting(CPUState *cs)
{
#ifdef CONFIG_TCG
/* Check whether this exception is a semihosting call; if so
* then handle it and return true; otherwise return false.
*/
@ -10474,6 +10477,9 @@ static inline bool check_for_semihosting(CPUState *cs)
env->regs[0] = do_arm_semihosting(env);
return true;
}
#else
return false;
#endif
}
/* Handle a CPU exception for A and R profile CPUs.