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authorLinus Torvalds <torvalds@linux-foundation.org>2026-09-05 11:59:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-09-05 11:59:05 -0700
commit9f0346dcbea363787186c94ef94dd01aaa215afa (patch)
treeb81c168f4d0dbe4c7f4750f4598d48a6deb72094 /samples/trace_printk
downloadlinux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.tar.gz
linux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.zip
Merge tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-coregrafted
Pull driver core fixes from Danilo Krummrich: - Fix kernfs listxattr() not returning security xattr names (e.g. SELinux labels) when the kernfs node has no allocated kernfs_iattrs - Fix silent truncation of IRQ vector indices in the Rust PCI abstractions - Don't select OF from DRIVER_PE_KUNIT_TEST; skip the test when OF is disabled instead of silently enabling extra kernel functionality - Russ Weight is retiring from kernel development; update the Firmware Loader sysfs contact to the driver-core mailing list, add a CREDITS entry for Firmware Upload, and update MAINTAINERS accordingly * tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: MAINTAINERS: Remove Russ Weight from Firmware Loader CREDITS: Add CREDITS entry for Firmware Upload firmware_loader: Change contact for sysfs nodes rust: pci: reject IRQ vector indices that do not fit in u32 kernfs: preserve security xattrs without allocating iattrs drivers: base: test: DRIVER_PE_KUNIT_TEST should not select OF
Diffstat (limited to 'samples/trace_printk')
-rw-r--r--samples/trace_printk/Makefile7
-rw-r--r--samples/trace_printk/trace-printk.c58
2 files changed, 65 insertions, 0 deletions
diff --git a/samples/trace_printk/Makefile b/samples/trace_printk/Makefile
new file mode 100644
index 000000000..c0df36167
--- /dev/null
+++ b/samples/trace_printk/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# builds a module that calls various trace_printk routines
+# then to use one (as root): insmod <module_name.ko>
+
+# This module can also be used to test the trace_printk code.
+
+obj-$(CONFIG_SAMPLE_TRACE_PRINTK) += trace-printk.o
diff --git a/samples/trace_printk/trace-printk.c b/samples/trace_printk/trace-printk.c
new file mode 100644
index 000000000..cfc159580
--- /dev/null
+++ b/samples/trace_printk/trace-printk.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/irq_work.h>
+
+/* Must not be static to force gcc to consider these non constant */
+char *trace_printk_test_global_str =
+ "This is a dynamic string that will use trace_puts\n";
+
+char *trace_printk_test_global_str_irq =
+ "(irq) This is a dynamic string that will use trace_puts\n";
+
+char *trace_printk_test_global_str_fmt =
+ "%sThis is a %s that will use trace_printk\n";
+
+static struct irq_work irqwork;
+
+static void trace_printk_irq_work(struct irq_work *work)
+{
+ trace_printk("(irq) This is a static string that will use trace_bputs\n");
+ trace_printk(trace_printk_test_global_str_irq);
+
+ trace_printk("(irq) This is a %s that will use trace_bprintk()\n",
+ "static string");
+
+ trace_printk(trace_printk_test_global_str_fmt,
+ "(irq) ", "dynamic string");
+}
+
+static int __init trace_printk_init(void)
+{
+ init_irq_work(&irqwork, trace_printk_irq_work);
+
+ trace_printk("This is a static string that will use trace_bputs\n");
+ trace_printk(trace_printk_test_global_str);
+
+ /* Kick off printing in irq context */
+ irq_work_queue(&irqwork);
+ irq_work_sync(&irqwork);
+
+ trace_printk("This is a %s that will use trace_bprintk()\n",
+ "static string");
+
+ trace_printk(trace_printk_test_global_str_fmt, "", "dynamic string");
+
+ return 0;
+}
+
+static void __exit trace_printk_exit(void)
+{
+}
+
+module_init(trace_printk_init);
+module_exit(trace_printk_exit);
+
+MODULE_AUTHOR("Steven Rostedt");
+MODULE_DESCRIPTION("trace-printk");
+MODULE_LICENSE("GPL");