uti: Clear user space PTEs after first fork in create_tracer()

Change-Id: I60755f0cb5e84c3a5a5cd91515411a30f0995822

executer/include/uprotocol.h

@@ -62,7 +62,7 @@
 #define MCEXEC_UP_TERMINATE_THREAD 0x30a02925
 #define MCEXEC_UP_GET_NUM_POOL_THREADS  0x30a02926
 #define MCEXEC_UP_UTI_ATTR       0x30a02927
-#define MCEXEC_UP_UNMAP_PSEUDO_FILEMAP 0x30a02928
+#define MCEXEC_UP_RELEASE_USER_SPACE 0x30a02928
 
 #define MCEXEC_UP_DEBUG_LOG     0x40000000
 
@@ -245,6 +245,11 @@ struct sys_unshare_desc {
 	unsigned long unshare_flags;
 };
 
+struct release_user_space_desc {
+	unsigned long user_start;
+	unsigned long user_end;
+};
+
 enum perf_ctrl_type {
 	PERF_CTRL_SET,
 	PERF_CTRL_GET,

executer/kernel/mcctrl/control.c

@@ -2517,14 +2517,19 @@ err:
 	return 0;
 }
  
-long mcexec_unmap_pseudo_filemap(ihk_os_t os, struct file *file)
+static long mcexec_release_user_space(struct release_user_space_desc *__user arg)
 {
-	long rc = -1;
+	struct release_user_space_desc desc;
-	struct mcos_handler_info *info;
+
-	info = ihk_os_get_mcos_private_data(file);
+	if (copy_from_user(&desc, arg, sizeof(desc))) {
-	dprintk("%s: clear_pte_range %p-%p\n", __FUNCTION__, (void*)info->user_start, (void*)info->user_end);
+		return -EFAULT;
-	rc = clear_pte_range(info->user_start, info->user_end - info->user_start);
+	}
-	return rc;
+
+#if 1
+	return clear_pte_range(desc.user_start, desc.user_end - desc.user_start);
+#else
+	return release_user_space(desc.user_start, desc.user_end - desc.user_start);
+#endif
 }
 
  static long (*mckernel_do_futex)(int n, unsigned long arg0, unsigned long arg1,
@@ -3017,8 +3022,8 @@ long __mcctrl_control(ihk_os_t os, unsigned int req, unsigned long arg,
 	case MCEXEC_UP_TERMINATE_THREAD:
 		return mcexec_terminate_thread(os, (unsigned long *)arg, file);
 
-	case MCEXEC_UP_UNMAP_PSEUDO_FILEMAP:
+	case MCEXEC_UP_RELEASE_USER_SPACE:
-		return mcexec_unmap_pseudo_filemap(os, file);
+		return mcexec_release_user_space((struct release_user_space_desc *)arg);
 
 	case MCEXEC_UP_GET_NUM_POOL_THREADS:
 		return mcctrl_get_num_pool_threads(os);

executer/kernel/mcctrl/driver.c

@@ -90,7 +90,7 @@ static struct ihk_os_user_call_handler mcctrl_uchs[] = {
 	{ .request = MCEXEC_UP_TERMINATE_THREAD, .func = mcctrl_ioctl },
 	{ .request = MCEXEC_UP_GET_NUM_POOL_THREADS, .func = mcctrl_ioctl },
 	{ .request = MCEXEC_UP_UTI_ATTR, .func = mcctrl_ioctl },
-	{ .request = MCEXEC_UP_UNMAP_PSEUDO_FILEMAP, .func = mcctrl_ioctl },
+	{ .request = MCEXEC_UP_RELEASE_USER_SPACE, .func = mcctrl_ioctl },
 	{ .request = MCEXEC_UP_DEBUG_LOG, .func = mcctrl_ioctl },
 	{ .request = IHK_OS_AUX_PERF_NUM, .func = mcctrl_ioctl },
 	{ .request = IHK_OS_AUX_PERF_SET, .func = mcctrl_ioctl },

executer/kernel/mcctrl/mcctrl.h

@@ -539,6 +539,7 @@ struct vdso {
 
 int reserve_user_space(struct mcctrl_usrdata *usrdata, unsigned long *startp,
 		unsigned long *endp);
+int release_user_space(uintptr_t start, uintptr_t len);
 void get_vdso_info(ihk_os_t os, long vdso_pa);
 int arch_symbols_init(void);
 

executer/kernel/mcctrl/syscall.c

@@ -2028,6 +2028,43 @@ int clear_pte_range(uintptr_t start, uintptr_t len)
 	return ret;
 }
 
+int release_user_space(uintptr_t start, uintptr_t len)
+{
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	uintptr_t addr;
+	uintptr_t end;
+	int error;
+	int ret;
+
+	ret = 0;
+	//down_read(&mm->mmap_sem);
+	addr = start;
+	while (addr < (start + len)) {
+		vma = find_vma(mm, addr);
+		if (!vma) {
+			break;
+		}
+
+		if (addr < vma->vm_start) {
+			addr = vma->vm_start;
+		}
+
+		end = vma->vm_end;
+		if (addr < end) {
+			if ((error = vm_munmap(addr, end - addr))) {
+				printk("%s: ERROR: vm_munmap failed (%d)\n", __func__, error);
+			}
+			if (ret == 0) {
+				ret = error;
+			}
+		}
+		addr = vma->vm_end;
+	}
+	//up_read(&mm->mmap_sem);
+	return ret;
+}
+
 /**
  * \brief Write out the core file image to a core file.
  *

executer/user/mcexec.c

@@ -1962,14 +1962,14 @@ struct uti_desc {
 	int exit; /* Used to tell the tracer to exit */
 };
 
-static int create_tracer();
+static int create_tracer(unsigned long user_start, unsigned long user_end);
 int uti_pfd[2];
 struct uti_desc *uti_desc = (void*)-1;
+static struct program_load_desc *desc;
 
 int main(int argc, char **argv)
 {
 	int ret = 0;
-	struct program_load_desc *desc;
 	int envs_len;
 	char *envs;
 	char *args;
@@ -2144,9 +2144,9 @@ int main(int argc, char **argv)
 	if (opendev() == -1)
 		exit(EXIT_FAILURE);
 
-#if 1
+#if 0
-	/* Create tracer before anonymous inode is mapped */
+	/* TODO: Remove this after memory corruption bug is fixed */
-	if ((error = create_tracer())) {
+	if ((error = create_tracer(0, 0))) {
 		fprintf(stderr, "%s: create tracer returned %d\n", __FUNCTION__, error);
 		return error;
 	}
@@ -2875,7 +2875,7 @@ debug_sig(int s)
 #endif
 
 static int
-create_tracer()
+create_tracer(unsigned long user_start, unsigned long user_end)
 {
 	int tpid;
 	int rc;
@@ -2888,6 +2888,10 @@ create_tracer()
 	int exited = 0;
 	int mode = 0;
 	unsigned long buf;
+	struct release_user_space_desc release_desc = {
+		.user_start = desc->user_start,
+		.user_end = desc->user_end
+	};
 
 	/* Perform mmap() before fork() in create_tracer() */
 	uti_desc = mmap(NULL, sizeof(struct uti_desc), PROT_READ | PROT_WRITE,
@@ -2942,6 +2946,12 @@ create_tracer()
 		return 0;
 	}
 	close(uti_pfd[0]);
+#if 1 /* debug */
+		if (ioctl(fd, MCEXEC_UP_RELEASE_USER_SPACE, &release_desc) != 0) {
+			fprintf(stderr, "%s: ERROR: MCEXEC_UP_RELEASE_USER_SPACE returned %d\n", __FUNCTION__, errno);
+			exit(1);
+		}
+#endif
 	tpid = fork();
 	if (tpid) {
 		if (tpid == -1) {
@@ -2966,9 +2976,14 @@ create_tracer()
 	}
 #endif
 
+#if 0
+	if (ioctl(fd, MCEXEC_UP_RELEASE_USER_SPACE, &release_desc) != 0) {
+		fprintf(stderr, "%s: ERROR: MCEXEC_UP_RELEASE_USER_SPACE returned %d\n", __FUNCTION__, errno);
+		exit(1);
+	}
+#endif
 	sem_wait(&uti_desc->arg);
 	if (uti_desc->exit) { /* When uti is not used */
-		fprintf(stderr, "%s: exiting tid=%d\n", __FUNCTION__, gettid());
 		exit(0);
 	}
 
@@ -3047,7 +3062,7 @@ create_tracer()
 				   return_syscall()
 			*/
 			if (exited == 1 || exited == 2) {
-				fprintf(stderr, "%s:  calling MCEXEC_UP_TERMINATE_THREAD,exited=%d,code=%lx\n", __FUNCTION__, exited, code);
+				__dprintf("calling MCEXEC_UP_TERMINATE_THREAD,exited=%d,code=%lx\n", exited, code);
 				if (ioctl(fd, MCEXEC_UP_TERMINATE_THREAD, term_param) != 0) {
 					fprintf(stderr, "%s: INFO: MCEXEC_UP_TERMINATE_THREAD returned %d\n", __FUNCTION__, errno);
 				}
@@ -3192,10 +3207,11 @@ util_thread(struct thread_data_s *my_thread, unsigned long uctx_pa, int remote_t
 	int rc = 0;
 	unsigned long buf;
 	
-#if 0
+#if 1
-	if ((error = create_tracer())) {
+	/* Create tracer */
-		fprintf(stderr, "%s: create_tracer returned %d\n", __FUNCTION__, error);
+	if ((rc = create_tracer(desc->user_start, desc->user_end))) {
-		rc = error; goto out;
+		fprintf(stderr, "%s: create_tracer returned %d\n", __FUNCTION__, rc);
+		goto out;
 	}
 #endif
 #ifdef POSTK_DEBUG_ARCH_DEP_35
@@ -3774,12 +3790,14 @@ gettid_out:
 					goto fork_child_sync_pipe;
 				}
 
-				/* Create tracer before anonymous inode is mapped */
+#if 1
-				if ((ret = create_tracer())) {
+				/* Create tracer */
+				if ((ret = create_tracer(desc->user_start, desc->user_end))) {
 					fs->status = ret;
 					fprintf(stderr, "%s: create tracer returned %d\n", __FUNCTION__, ret);
 					goto fork_child_sync_pipe;
 				}
+#endif
 				
 				if (ioctl(fd, MCEXEC_UP_CREATE_PPD) != 0) {
 					fs->status = -errno;