[LTP] [PATCH v7 4/4] fw_load: add fw_load02 for custom firmware path
Andrea Cervesato
andrea.cervesato@suse.de
Mon Jun 15 14:12:48 CEST 2026
From: Andrea Cervesato <andrea.cervesato@suse.com>
Add fw_load02 which points the kernel firmware loader at the writable
LTP temporary directory via /sys/module/firmware_class/parameters/path.
Unlike fw_load01, it does not rely on a writable /lib/firmware and so
works on read-only and immutable root filesystems while still exercising
request_firmware() for both successful loads and the not-found case.
Move test inside the header so both fw_load01 and fw_load02 will share
the same test function.
Signed-off-by: Andrea Cervesato <andrea.cervesato@suse.com>
---
runtest/kernel_misc | 1 +
testcases/kernel/firmware/fw_load/.gitignore | 1 +
testcases/kernel/firmware/fw_load/Makefile | 2 +-
testcases/kernel/firmware/fw_load/fw_load.h | 69 ++++++++++++++++++++
testcases/kernel/firmware/fw_load/fw_load01.c | 72 +++------------------
testcases/kernel/firmware/fw_load/fw_load02.c | 93 +++++++++++++++++++++++++++
6 files changed, 174 insertions(+), 64 deletions(-)
diff --git a/runtest/kernel_misc b/runtest/kernel_misc
index 19caee1d81da9cf0503088138ecfda13436b96cf..cc3562cb78cfa9b657692fcbd8fb732f2879092e 100644
--- a/runtest/kernel_misc
+++ b/runtest/kernel_misc
@@ -1,6 +1,7 @@
cn_pec_sh cn_pec.sh
kmsg01 kmsg01
fw_load01 fw_load01
+fw_load02 fw_load02
rtc01 rtc01
rtc02 rtc02
block_dev block_dev
diff --git a/testcases/kernel/firmware/fw_load/.gitignore b/testcases/kernel/firmware/fw_load/.gitignore
index 57eca444c161e6ba642561664cc7de3a8f134841..0bacefd371fc3ac6cf043102398b5a0c74b0b66d 100644
--- a/testcases/kernel/firmware/fw_load/.gitignore
+++ b/testcases/kernel/firmware/fw_load/.gitignore
@@ -6,3 +6,4 @@
/.tmp_versions/
modules.livepatch
fw_load01
+fw_load02
diff --git a/testcases/kernel/firmware/fw_load/Makefile b/testcases/kernel/firmware/fw_load/Makefile
index 91e8d8d153b43c459a899aff2124db612ec9e960..bf6f9abd7517654066a5a92ac481e8eb1f959a41 100644
--- a/testcases/kernel/firmware/fw_load/Makefile
+++ b/testcases/kernel/firmware/fw_load/Makefile
@@ -17,7 +17,7 @@ include $(top_srcdir)/include/mk/testcases.mk
REQ_VERSION_MAJOR := 3
REQ_VERSION_PATCH := 7
-MAKE_TARGETS := fw_load01 ltp_fw_load.ko
+MAKE_TARGETS := fw_load01 fw_load02 ltp_fw_load.ko
include $(top_srcdir)/include/mk/module.mk
include $(top_srcdir)/include/mk/generic_leaf_target.mk
diff --git a/testcases/kernel/firmware/fw_load/fw_load.h b/testcases/kernel/firmware/fw_load/fw_load.h
index 39f207cc30810e2ed9ea76176cedd98aa902d887..9692c0c90e046d1c13d3082d187076b2b43f84f5 100644
--- a/testcases/kernel/firmware/fw_load/fw_load.h
+++ b/testcases/kernel/firmware/fw_load/fw_load.h
@@ -6,6 +6,8 @@
#ifndef FW_LOAD_H
#define FW_LOAD_H
+#include "tst_test.h"
+
#define MNAME_KO "ltp_fw_load.ko"
#define FW_NAME "load_tst.fw"
#define FW_SIZE 0x1000
@@ -15,4 +17,71 @@
#define DEV_RESULT "/sys/devices/ltp_fw_load/result"
#define LIB_PATH "/lib/firmware"
+struct fw_data {
+ char dir[PATH_MAX];
+ char file[PATH_MAX];
+ int fake;
+ int created_dir;
+};
+
+static inline void create_firmware(struct fw_data *firmware,
+ int *fw_count, const char *dir)
+{
+ struct fw_data *fw = &firmware[*fw_count];
+ char buf[FW_SIZE];
+ int fd;
+
+ snprintf(fw->dir, sizeof(fw->dir), "%s", dir);
+
+ if (access(dir, X_OK) == -1) {
+ SAFE_MKDIR(dir, 0755);
+ fw->created_dir = 1;
+ }
+
+ snprintf(fw->file, sizeof(fw->file), "%s/n%d_%s", dir, *fw_count, FW_NAME);
+ memset(buf, *fw_count, FW_SIZE);
+
+ fd = SAFE_OPEN(fw->file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
+ SAFE_WRITE(SAFE_WRITE_ALL, fd, buf, FW_SIZE);
+ SAFE_CLOSE(fd);
+
+ (*fw_count)++;
+}
+
+static inline void create_fake_firmware(struct fw_data *firmware, int *fw_count)
+{
+ snprintf(firmware[*fw_count].file, sizeof(firmware[*fw_count].file),
+ "/n%d_%s", *fw_count, FW_NAME);
+
+ firmware[*fw_count].fake = 1;
+ (*fw_count)++;
+}
+
+static inline void do_test(struct fw_data *firmware, int fw_count)
+{
+ struct fw_data *fw;
+ int result = 0;
+ int pass, offset;
+
+ SAFE_FILE_PRINTF(DEV_FWNUM, "%d", fw_count);
+ SAFE_FILE_SCANF(DEV_RESULT, "%d", &result);
+
+ for (int i = 0; i < fw_count; i++) {
+ fw = &firmware[i];
+
+ pass = result & (1 << i);
+ offset = fw->dir[0] ? strlen(fw->dir) : 0;
+
+ if (fw->fake) {
+ tst_res(pass ? TFAIL : TPASS,
+ "Firmware '%s' correctly not loaded",
+ fw->file + offset);
+ } else {
+ tst_res(pass ? TPASS : TFAIL,
+ "Firmware '%s' loaded",
+ fw->file + offset);
+ }
+ }
+}
+
#endif
diff --git a/testcases/kernel/firmware/fw_load/fw_load01.c b/testcases/kernel/firmware/fw_load/fw_load01.c
index 402e2c71f508fdbb9c3f73fcd42bf87da280137b..4b30a3b40fb1e3db8f300b2c56d5f29e8e37a7ff 100644
--- a/testcases/kernel/firmware/fw_load/fw_load01.c
+++ b/testcases/kernel/firmware/fw_load/fw_load01.c
@@ -40,61 +40,11 @@
static int module_loaded;
static int fw_count;
-
-static struct fw_data {
- char dir[PATH_MAX];
- char file[PATH_MAX];
- int fake;
- int created_dir;
-} firmware[FW_NUM];
-
-static void create_firmware(const char *dir)
-{
- struct fw_data *fw = &firmware[fw_count];
- char buf[FW_SIZE];
- int fd = -1;
-
- snprintf(fw->dir, sizeof(fw->dir), "%s", dir);
- if (access(dir, X_OK) == -1) {
- SAFE_MKDIR(dir, 0755);
- fw->created_dir = 1;
- }
-
- snprintf(fw->file, sizeof(fw->file), "%s/n%d_%s", dir, fw_count, FW_NAME);
- memset(buf, fw_count, FW_SIZE);
-
- fd = SAFE_OPEN(fw->file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
- SAFE_WRITE(SAFE_WRITE_ALL, fd, buf, FW_SIZE);
- SAFE_CLOSE(fd);
-
- fw_count++;
-}
+static struct fw_data firmware[FW_NUM];
static void run(void)
{
- struct fw_data *fw;
- int result = 0;
- int pass, offset;
-
- SAFE_FILE_PRINTF(DEV_FWNUM, "%d", fw_count);
- SAFE_FILE_SCANF(DEV_RESULT, "%d", &result);
-
- for (int i = 0; i < fw_count; i++) {
- fw = &firmware[i];
-
- pass = result & (1 << i);
- offset = fw->dir[0] ? strlen(fw->dir) : 0;
-
- if (fw->fake) {
- tst_res(pass ? TFAIL : TPASS,
- "Firmware '%s' correctly not loaded",
- fw->file + offset);
- } else {
- tst_res(pass ? TPASS : TFAIL,
- "Firmware '%s' loaded",
- fw->file + offset);
- }
- }
+ do_test(firmware, fw_count);
}
static void setup(void)
@@ -104,7 +54,8 @@ static void setup(void)
struct utsname name;
if (access(LIB_PATH, W_OK) == -1)
- tst_brk(TCONF, "Skipping test due to read-only %s", LIB_PATH);
+ tst_brk(TCONF, "Skipping test due to read-only %s",
+ LIB_PATH);
tst_requires_module_signature_disabled();
@@ -114,25 +65,20 @@ static void setup(void)
tst_module_load(MNAME_KO, mod_params);
module_loaded = 1;
- create_firmware(LIB_PATH);
+ create_firmware(firmware, &fw_count, LIB_PATH);
uname(&name);
snprintf(fw_dir, sizeof(fw_dir), "%s/%s", LIB_PATH, name.release);
- create_firmware(fw_dir);
+ create_firmware(firmware, &fw_count, fw_dir);
snprintf(fw_dir, sizeof(fw_dir), "%s/updates", LIB_PATH);
- create_firmware(fw_dir);
+ create_firmware(firmware, &fw_count, fw_dir);
snprintf(fw_dir, sizeof(fw_dir), "%s/updates/%s", LIB_PATH, name.release);
- create_firmware(fw_dir);
-
- /* add a fake file */
- snprintf(firmware[fw_count].file, sizeof(firmware[fw_count].file),
- "/n%d_%s", fw_count, FW_NAME);
+ create_firmware(firmware, &fw_count, fw_dir);
- firmware[fw_count].fake = 1;
- fw_count++;
+ create_fake_firmware(firmware, &fw_count);
}
static void cleanup(void)
diff --git a/testcases/kernel/firmware/fw_load/fw_load02.c b/testcases/kernel/firmware/fw_load/fw_load02.c
new file mode 100644
index 0000000000000000000000000000000000000000..8d2063772c0f0aadeb5e46fcba6bf2a6bba4d327
--- /dev/null
+++ b/testcases/kernel/firmware/fw_load/fw_load02.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2013 Oracle and/or its affiliates. All Rights Reserved.
+ * Alexey Kodanev <alexey.kodanev@oracle.com>
+ * Copyright (c) 2026 SUSE LLC Andrea Cervesato <andrea.cervesato@suse.com>
+ */
+
+/*\
+ * Verifies that the kernel firmware loader (``CONFIG_FW_LOADER``)
+ * can find and load firmware files from a custom firmware search
+ * path.
+ *
+ * A helper kernel module (``ltp_fw_load.ko``) registers a virtual
+ * device that calls :kernel_doc:`request_firmware` for a set of
+ * numbered firmware blobs. Each blob is verified in-kernel against
+ * its expected size and byte pattern.
+ *
+ * The kernel firmware loader is pointed at the writable LTP
+ * temporary directory through
+ * ``/sys/module/firmware_class/parameters/path``.
+ * This avoids writing into ``/lib/firmware`` and therefore works
+ * on read-only or immutable root filesystems. The original value
+ * is saved and restored automatically.
+ *
+ * [Algorithm]
+ *
+ * - Set the firmware search path to the LTP temporary directory
+ * - Load the helper module with ``fw_size`` matching the blob size
+ * - Create ``FW_NUM - 1`` firmware files there, each named
+ * ``n<i>_load_tst.fw`` and filled with a known byte pattern
+ * - Add one fake firmware entry that has no file on disk
+ * - Write the firmware count to ``/sys/devices/ltp_fw_load/fwnum``
+ * to trigger :kernel_doc:`request_firmware` calls in-kernel
+ * - Read the result bitmask from ``/sys/devices/ltp_fw_load/result``
+ * - Verify that every real firmware file was loaded successfully
+ * and that the fake entry was correctly rejected
+ */
+
+#include "tst_test.h"
+#include "tst_module.h"
+#include "fw_load.h"
+
+static int module_loaded;
+static int fw_count;
+static struct fw_data firmware[FW_NUM];
+
+static void run(void)
+{
+ do_test(firmware, fw_count);
+}
+
+static void setup(void)
+{
+ char fw_size_param[32];
+ char *tmpdir = tst_tmpdir_path();
+
+ tst_requires_module_signature_disabled();
+
+ SAFE_FILE_PRINTF(FW_PATH, "%s", tmpdir);
+
+ snprintf(fw_size_param, sizeof(fw_size_param), "fw_size=%d", FW_SIZE);
+ char *const mod_params[] = {fw_size_param, NULL};
+
+ tst_module_load(MNAME_KO, mod_params);
+ module_loaded = 1;
+
+ for (int i = 0; i < FW_NUM - 1; i++)
+ create_firmware(firmware, &fw_count, tmpdir);
+
+ create_fake_firmware(firmware, &fw_count);
+}
+
+static void cleanup(void)
+{
+ if (module_loaded)
+ tst_module_unload(MNAME_KO);
+}
+
+static struct tst_test test = {
+ .test_all = run,
+ .setup = setup,
+ .cleanup = cleanup,
+ .needs_root = 1,
+ .needs_tmpdir = 1,
+ .needs_kconfigs = (const char *[]) {
+ "CONFIG_FW_LOADER=y|CONFIG_FW_LOADER=m",
+ NULL,
+ },
+ .save_restore = (const struct tst_path_val[]) {
+ {FW_PATH, NULL, TST_SR_TCONF},
+ {},
+ },
+};
--
2.51.0
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