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Currently on boot up and when modules are loaded, the trace event infrastructure will examine the TP_printk's of every event looking to see if it dereferences pointers on the ring buffer via printk formats like "%pB" and such. What it doesn't do is check if the arguments themselves do a dereference from a pointer. This was brought with a fix[1] to the fsl_edma event that had in the arguments of the TP_printk(): "__entry->edma->membase" The __entry->edma is a pointer saved in the ring buffer. The dereference from TP_printk() happens when the user reads the "trace" file which can be seconds, minutes, hours, days, weeks, or even months later! There is no guarantee that the __entry->edma pointer will still be pointing to what it was when it was recorded, and could crash the kernel when a user reads the event. Add logic to the test_event_printk() that also checks for this case and warn if the event dereferences a pointer from the ring buffer. [1] https://lore.kernel.org/all/20260630200022.1826420-1-martin@kaiser.cx/ Link: https://patch.msgid.link/20260630184836.74d477b6@gandalf.local.home Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Martin Kaiser <martin@kaiser.cx> Reviewed-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>