On Thu, Sep 2, 2021 at 9:17 AM Philippe Mathieu-Daudé <
f4bug@amsat.org> wrote:
do_interrupt() is sysemu specific. However due to some X86
specific hack, it is also used in user-mode emulation, which
is why it couldn't be restricted to CONFIG_SOFTMMU (see the
comment around added in commit 78271684719: "cpu: tcg_ops:
move to tcg-cpu-ops.h, keep a pointer in CPUClass").
Keep the hack but rename the handler as fake_user_exception()
and restrict do_interrupt() to sysemu.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
RFC: Any better name / idea here?
Maybe user_mode_exception()? but I'm not sure that's better...
---
include/hw/core/tcg-cpu-ops.h | 22 ++++++++++++++--------
accel/tcg/cpu-exec.c | 4 ++--
target/i386/tcg/tcg-cpu.c | 6 ++++--
3 files changed, 20 insertions(+), 12 deletions(-)
diff --git a/include/hw/core/tcg-cpu-ops.h b/include/hw/core/tcg-cpu-ops.h
index eab27d0c030..600f0349659 100644
--- a/include/hw/core/tcg-cpu-ops.h
+++ b/include/hw/core/tcg-cpu-ops.h
@@ -37,14 +37,6 @@ struct TCGCPUOps {
void (*cpu_exec_exit)(CPUState *cpu);
/** @cpu_exec_interrupt: Callback for processing interrupts in cpu_exec */
bool (*cpu_exec_interrupt)(CPUState *cpu, int interrupt_request);
- /**
- * @do_interrupt: Callback for interrupt handling.
- *
- * note that this is in general SOFTMMU only, but it actually isn't
- * because of an x86 hack (accel/tcg/cpu-exec.c), so we cannot put it
- * in the SOFTMMU section in general.
- */
- void (*do_interrupt)(CPUState *cpu);
/**
* @tlb_fill: Handle a softmmu tlb miss or user-only address fault
*
@@ -61,6 +53,20 @@ struct TCGCPUOps {
void (*debug_excp_handler)(CPUState *cpu);
#ifdef NEED_CPU_H
+#if defined(CONFIG_USER_ONLY) && defined(TARGET_I386)
+ /**
+ * @fake_user_exception: Callback for 'fake exception' handling.
+ *
+ * Simulate 'fake exception' which will be handled outside the
+ * cpu execution loop (hack for x86 user mode).
+ */
+ void (*fake_user_exception)(CPUState *cpu);
+#else
+ /**
+ * @do_interrupt: Callback for interrupt handling.
+ */
+ void (*do_interrupt)(CPUState *cpu);
+#endif /* !CONFIG_USER_ONLY || !TARGET_I386 */
#ifdef CONFIG_SOFTMMU
/**
* @do_transaction_failed: Callback for handling failed memory transactions
diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c
index e5c0ccd1a2a..3e387c944c5 100644
--- a/accel/tcg/cpu-exec.c
+++ b/accel/tcg/cpu-exec.c
@@ -651,8 +651,8 @@ static inline bool cpu_handle_exception(CPUState *cpu, int *ret)
loop */
#if defined(TARGET_I386)
CPUClass *cc = CPU_GET_CLASS(cpu);
- cc->tcg_ops->do_interrupt(cpu);
-#endif
+ cc->tcg_ops->fake_user_exception(cpu);
+#endif /* TARGET_I386 */
*ret = cpu->exception_index;
cpu->exception_index = -1;
return true;
diff --git a/target/i386/tcg/tcg-cpu.c b/target/i386/tcg/tcg-cpu.c
index 93a79a57415..dce800a8953 100644
--- a/target/i386/tcg/tcg-cpu.c
+++ b/target/i386/tcg/tcg-cpu.c
@@ -73,9 +73,11 @@ static const struct TCGCPUOps x86_tcg_ops = {
.cpu_exec_enter = x86_cpu_exec_enter,
.cpu_exec_exit = x86_cpu_exec_exit,
.cpu_exec_interrupt = x86_cpu_exec_interrupt,
- .do_interrupt = x86_cpu_do_interrupt,
.tlb_fill = x86_cpu_tlb_fill,
-#ifndef CONFIG_USER_ONLY
+#ifdef CONFIG_USER_ONLY
+ .fake_user_exception = x86_cpu_do_interrupt,
+#else
+ .do_interrupt = x86_cpu_do_interrupt,
.debug_excp_handler = breakpoint_handler,
.debug_check_breakpoint = x86_debug_check_breakpoint,
#endif /* !CONFIG_USER_ONLY */
--
2.31.1