Merge tag 'driver-core-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the "big" set of driver core changes for 5.7-rc1.

  Nothing huge in here, just lots of little firmware core changes and
  use of new apis, a libfs fix, a debugfs api change, and some driver
  core deferred probe rework.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (44 commits)
  Revert "driver core: Set fw_devlink to "permissive" behavior by default"
  driver core: Set fw_devlink to "permissive" behavior by default
  driver core: Replace open-coded list_last_entry()
  driver core: Read atomic counter once in driver_probe_done()
  libfs: fix infoleak in simple_attr_read()
  driver core: Add device links from fwnode only for the primary device
  platform/x86: touchscreen_dmi: Add info for the Chuwi Vi8 Plus tablet
  platform/x86: touchscreen_dmi: Add EFI embedded firmware info support
  Input: icn8505 - Switch to firmware_request_platform for retreiving the fw
  Input: silead - Switch to firmware_request_platform for retreiving the fw
  selftests: firmware: Add firmware_request_platform tests
  test_firmware: add support for firmware_request_platform
  firmware: Add new platform fallback mechanism and firmware_request_platform()
  Revert "drivers: base: power: wakeup.c: Use built-in RCU list checking"
  drivers: base: power: wakeup.c: Use built-in RCU list checking
  component: allow missing unbind callback
  debugfs: remove return value of debugfs_create_file_size()
  debugfs: Check module state before warning in {full/open}_proxy_open()
  firmware: fix a double abort case with fw_load_sysfs_fallback
  arch_topology: Fix putting invalid cpu clk
  ...

tools/testing/selftests/firmware/Makefile

@@ -1,13 +1,10 @@
 # SPDX-License-Identifier: GPL-2.0-only
 # Makefile for firmware loading selftests
-
-# No binaries, but make sure arg-less "make" doesn't trigger "run_tests"
-all:
+CFLAGS = -Wall \
+         -O2
 
 TEST_PROGS := fw_run_tests.sh
 TEST_FILES := fw_fallback.sh fw_filesystem.sh fw_lib.sh
+TEST_GEN_FILES := fw_namespace
 
 include ../lib.mk
-
-# Nothing to clean up.
-clean:

tools/testing/selftests/firmware/fw_filesystem.sh

@@ -86,6 +86,29 @@ else
 	fi
 fi
 
+# Try platform (EFI embedded fw) loading too
+if [ ! -e "$DIR"/trigger_request_platform ]; then
+	echo "$0: firmware loading: platform trigger not present, ignoring test" >&2
+else
+	if printf '\000' >"$DIR"/trigger_request_platform 2> /dev/null; then
+		echo "$0: empty filename should not succeed (platform)" >&2
+		exit 1
+	fi
+
+	# Note we echo a non-existing name, since files on the file-system
+	# are preferred over firmware embedded inside the platform's firmware
+	# The test adds a fake entry with the requested name to the platform's
+	# fw list, so the name does not matter as long as it does not exist
+	if ! echo -n "nope-$NAME" >"$DIR"/trigger_request_platform ; then
+		echo "$0: could not trigger request platform" >&2
+		exit 1
+	fi
+
+	# The test verifies itself that the loaded firmware contents matches
+	# the contents for the fake platform fw entry it added.
+	echo "$0: platform loading works"
+fi
+
 ### Batched requests tests
 test_config_present()
 {

tools/testing/selftests/firmware/fw_namespace.c

@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Test triggering of loading of firmware from different mount
+ * namespaces. Expect firmware to be always loaded from the mount
+ * namespace of PID 1. */
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <sched.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#ifndef CLONE_NEWNS
+# define CLONE_NEWNS 0x00020000
+#endif
+
+static char *fw_path = NULL;
+
+static void die(char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	if (fw_path)
+		unlink(fw_path);
+	umount("/lib/firmware");
+	exit(EXIT_FAILURE);
+}
+
+static void trigger_fw(const char *fw_name, const char *sys_path)
+{
+	int fd;
+
+	fd = open(sys_path, O_WRONLY);
+	if (fd < 0)
+		die("open failed: %s\n",
+		    strerror(errno));
+	if (write(fd, fw_name, strlen(fw_name)) != strlen(fw_name))
+		exit(EXIT_FAILURE);
+	close(fd);
+}
+
+static void setup_fw(const char *fw_path)
+{
+	int fd;
+	const char fw[] = "ABCD0123";
+
+	fd = open(fw_path, O_WRONLY | O_CREAT, 0600);
+	if (fd < 0)
+		die("open failed: %s\n",
+		    strerror(errno));
+	if (write(fd, fw, sizeof(fw) -1) != sizeof(fw) -1)
+		die("write failed: %s\n",
+		    strerror(errno));
+	close(fd);
+}
+
+static bool test_fw_in_ns(const char *fw_name, const char *sys_path, bool block_fw_in_parent_ns)
+{
+	pid_t child;
+
+	if (block_fw_in_parent_ns)
+		if (mount("test", "/lib/firmware", "tmpfs", MS_RDONLY, NULL) == -1)
+			die("blocking firmware in parent ns failed\n");
+
+	child = fork();
+	if (child == -1) {
+		die("fork failed: %s\n",
+			strerror(errno));
+	}
+	if (child != 0) { /* parent */
+		pid_t pid;
+		int status;
+
+		pid = waitpid(child, &status, 0);
+		if (pid == -1) {
+			die("waitpid failed: %s\n",
+				strerror(errno));
+		}
+		if (pid != child) {
+			die("waited for %d got %d\n",
+				child, pid);
+		}
+		if (!WIFEXITED(status)) {
+			die("child did not terminate cleanly\n");
+		}
+		if (block_fw_in_parent_ns)
+			umount("/lib/firmware");
+		return WEXITSTATUS(status) == EXIT_SUCCESS ? true : false;
+	}
+
+	if (unshare(CLONE_NEWNS) != 0) {
+		die("unshare(CLONE_NEWNS) failed: %s\n",
+			strerror(errno));
+	}
+	if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) == -1)
+		die("remount root in child ns failed\n");
+
+	if (!block_fw_in_parent_ns) {
+		if (mount("test", "/lib/firmware", "tmpfs", MS_RDONLY, NULL) == -1)
+			die("blocking firmware in child ns failed\n");
+	} else
+		umount("/lib/firmware");
+
+	trigger_fw(fw_name, sys_path);
+
+	exit(EXIT_SUCCESS);
+}
+
+int main(int argc, char **argv)
+{
+	const char *fw_name = "test-firmware.bin";
+	char *sys_path;
+	if (argc != 2)
+		die("usage: %s sys_path\n", argv[0]);
+
+	/* Mount tmpfs to /lib/firmware so we don't have to assume
+	   that it is writable for us.*/
+	if (mount("test", "/lib/firmware", "tmpfs", 0, NULL) == -1)
+		die("mounting tmpfs to /lib/firmware failed\n");
+
+	sys_path = argv[1];
+	asprintf(&fw_path, "/lib/firmware/%s", fw_name);
+
+	setup_fw(fw_path);
+
+	setvbuf(stdout, NULL, _IONBF, 0);
+	/* Positive case: firmware in PID1 mount namespace */
+	printf("Testing with firmware in parent namespace (assumed to be same file system as PID1)\n");
+	if (!test_fw_in_ns(fw_name, sys_path, false))
+		die("error: failed to access firmware\n");
+
+	/* Negative case: firmware in child mount namespace, expected to fail */
+	printf("Testing with firmware in child namespace\n");
+	if (test_fw_in_ns(fw_name, sys_path, true))
+		die("error: firmware access did not fail\n");
+
+	unlink(fw_path);
+	free(fw_path);
+	umount("/lib/firmware");
+	exit(EXIT_SUCCESS);
+}

tools/testing/selftests/firmware/fw_run_tests.sh

@@ -61,6 +61,10 @@ run_test_config_0003()
 check_mods
 check_setup
 
+echo "Running namespace test: "
+$TEST_DIR/fw_namespace $DIR/trigger_request
+echo "OK"
+
 if [ -f $FW_FORCE_SYSFS_FALLBACK ]; then
 	run_test_config_0001
 	run_test_config_0002