Fix #81206: Multiple PHP processes crash with JIT enabled

We need to avoid resetting the JIT for all SAPIs, but we need to
initialize the JIT handlers even when only reattaching on Windows.

Closes GH-7208.

Author: cmb69

NEWS

@@ -16,6 +16,8 @@ PHP                                                                        NEWS
     (Dmitry)
   . Fixed bug #81249 (Intermittent property assignment failure with JIT
     enabled). (Dmitry)
+  . Fixed bug #81206 (Multiple PHP processes crash with JIT enabled). (cmb,
+    Nikita)
 
 - Standard:
   . Fixed bug #72146 (Integer overflow on substr_replace). (cmb)

ext/opcache/ZendAccelerator.c

@@ -3008,7 +3008,7 @@ static zend_result accel_post_startup(void)
 				zend_accel_error(ACCEL_LOG_FATAL, "Failure to initialize shared memory structures - probably not enough shared memory.");
 				return SUCCESS;
 			case SUCCESSFULLY_REATTACHED:
-#if defined(HAVE_JIT) && !defined(ZEND_WIN32)
+#ifdef HAVE_JIT
 				reattached = 1;
 #endif
 				zend_shared_alloc_lock();

ext/opcache/jit/zend_jit.c

@@ -4044,24 +4044,8 @@ ZEND_EXT_API void zend_jit_protect(void)
 #endif
 }
 
-static int zend_jit_make_stubs(void)
+static void zend_jit_init_handlers(void)
 {
-	dasm_State* dasm_state = NULL;
-	uint32_t i;
-
-	dasm_init(&dasm_state, DASM_MAXSECTION);
-	dasm_setupglobal(&dasm_state, dasm_labels, zend_lb_MAX);
-
-	for (i = 0; i < sizeof(zend_jit_stubs)/sizeof(zend_jit_stubs[0]); i++) {
-		dasm_setup(&dasm_state, dasm_actions);
-		if (!zend_jit_stubs[i].stub(&dasm_state)) {
-			return 0;
-		}
-		if (!dasm_link_and_encode(&dasm_state, NULL, NULL, NULL, NULL, zend_jit_stubs[i].name, 0)) {
-			return 0;
-		}
-	}
-
 	if (zend_jit_vm_kind == ZEND_VM_KIND_HYBRID) {
 		zend_jit_runtime_jit_handler = dasm_labels[zend_lbhybrid_runtime_jit];
 		zend_jit_profile_jit_handler = dasm_labels[zend_lbhybrid_profile_jit];
@@ -4079,6 +4063,27 @@ static int zend_jit_make_stubs(void)
 		zend_jit_ret_trace_counter_handler = (const void*)zend_jit_ret_trace_helper;
 		zend_jit_loop_trace_counter_handler = (const void*)zend_jit_loop_trace_helper;
 	}
+}
+
+static int zend_jit_make_stubs(void)
+{
+	dasm_State* dasm_state = NULL;
+	uint32_t i;
+
+	dasm_init(&dasm_state, DASM_MAXSECTION);
+	dasm_setupglobal(&dasm_state, dasm_labels, zend_lb_MAX);
+
+	for (i = 0; i < sizeof(zend_jit_stubs)/sizeof(zend_jit_stubs[0]); i++) {
+		dasm_setup(&dasm_state, dasm_actions);
+		if (!zend_jit_stubs[i].stub(&dasm_state)) {
+			return 0;
+		}
+		if (!dasm_link_and_encode(&dasm_state, NULL, NULL, NULL, NULL, zend_jit_stubs[i].name, 0)) {
+			return 0;
+		}
+	}
+
+	zend_jit_init_handlers();
 
 	dasm_free(&dasm_state);
 	return 1;
@@ -4353,6 +4358,7 @@ ZEND_EXT_API int zend_jit_startup(void *buf, size_t size, zend_bool reattached)
 #if _WIN32
 		/* restore global labels */
 		memcpy(dasm_labels, dasm_buf, sizeof(void*) * zend_lb_MAX);
+		zend_jit_init_handlers();
 #endif
 	}