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authorHaojie Li <lihaojie@kylinos.cn>2026-08-25 18:08:45 +0800
committerChun-Kuang Hu <chunkuang.hu@kernel.org>2026-09-28 23:20:55 +0000
commitbce7698e2e6565bb765bd0522337f29f5f312624 (patch)
tree0b735b7b4a27369cb4d75d9431b3ee59ce7e5bcc /samples/ftrace/sample-trace-array.h
downloadlinux-stable-bce7698e2e6565bb765bd0522337f29f5f312624.tar.gz
linux-stable-bce7698e2e6565bb765bd0522337f29f5f312624.zip
drm/mediatek: Add missing IS_ERR check for ovl_adaptor platform devicegrafted
platform_device_register_data() can fail and return an ERR_PTR, but the return value is used without checking, leading to an invalid pointer being stored in ddp_comp[].dev and passed to component_match_add() and mtk_ddp_comp_init(), which could result in a kernel crash. Add an IS_ERR() check to jump to the error handling path on failure. Fixes: 0d9eee9118b7 ("drm/mediatek: Add drm ovl_adaptor sub driver for MT8195") Cc: stable@vger.kernel.org Signed-off-by: Haojie Li <lihaojie@kylinos.cn> Reviewed-by: CK Hu <ck.hu@mediatek.com> Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20260825100845.438893-1-lihaojie@kylinos.cn/ Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Diffstat (limited to 'samples/ftrace/sample-trace-array.h')
-rw-r--r--samples/ftrace/sample-trace-array.h84
1 files changed, 84 insertions, 0 deletions
diff --git a/samples/ftrace/sample-trace-array.h b/samples/ftrace/sample-trace-array.h
new file mode 100644
index 000000000..6f8962428
--- /dev/null
+++ b/samples/ftrace/sample-trace-array.h
@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*
+ * If TRACE_SYSTEM is defined, that will be the directory created
+ * in the ftrace directory under /sys/kernel/tracing/events/<system>
+ *
+ * The define_trace.h below will also look for a file name of
+ * TRACE_SYSTEM.h where TRACE_SYSTEM is what is defined here.
+ * In this case, it would look for sample-trace.h
+ *
+ * If the header name will be different than the system name
+ * (as in this case), then you can override the header name that
+ * define_trace.h will look up by defining TRACE_INCLUDE_FILE
+ *
+ * This file is called sample-trace-array.h but we want the system
+ * to be called "sample-subsystem". Therefore we must define the name of this
+ * file:
+ *
+ * #define TRACE_INCLUDE_FILE sample-trace-array
+ *
+ * As we do in the bottom of this file.
+ *
+ * Notice that TRACE_SYSTEM should be defined outside of #if
+ * protection, just like TRACE_INCLUDE_FILE.
+ */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM sample-subsystem
+
+/*
+ * TRACE_SYSTEM is expected to be a C valid variable (alpha-numeric
+ * and underscore), although it may start with numbers. If for some
+ * reason it is not, you need to add the following lines:
+ */
+#undef TRACE_SYSTEM_VAR
+#define TRACE_SYSTEM_VAR sample_subsystem
+
+/*
+ * But the above is only needed if TRACE_SYSTEM is not alpha-numeric
+ * and underscored. By default, TRACE_SYSTEM_VAR will be equal to
+ * TRACE_SYSTEM. As TRACE_SYSTEM_VAR must be alpha-numeric, if
+ * TRACE_SYSTEM is not, then TRACE_SYSTEM_VAR must be defined with
+ * only alpha-numeric and underscores.
+ *
+ * The TRACE_SYSTEM_VAR is only used internally and not visible to
+ * user space.
+ */
+
+/*
+ * Notice that this file is not protected like a normal header.
+ * We also must allow for rereading of this file. The
+ *
+ * || defined(TRACE_HEADER_MULTI_READ)
+ *
+ * serves this purpose.
+ */
+#if !defined(_SAMPLE_TRACE_ARRAY_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _SAMPLE_TRACE_ARRAY_H
+
+#include <linux/tracepoint.h>
+TRACE_EVENT(sample_event,
+
+ TP_PROTO(int count, unsigned long time),
+
+ TP_ARGS(count, time),
+
+ TP_STRUCT__entry(
+ __field(int, count)
+ __field(unsigned long, time)
+ ),
+
+ TP_fast_assign(
+ __entry->count = count;
+ __entry->time = time;
+ ),
+
+ TP_printk("count value=%d at jiffies=%lu", __entry->count,
+ __entry->time)
+ );
+#endif
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE sample-trace-array
+#include <trace/define_trace.h>