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X-MS-Exchange-Transport-CrossTenantHeadersStamped: YQBPR0101MB5736 On 2026-04-29 11:43, Steven Rostedt wrote: [...] AFAIU this is a functional iteration of my prior RFC here: https://lore.kernel.org/lkml/2fa31347-3021-4604-bec3-e5a2d57b77b5@efficios.com/ perhaps it would be valuable to refer to that thread ? > } > + > +/** > + * sys_stacktrace_setup - register an address for user space stacktrace walking. > + * @op: Type of operation to perform > + * @addr_start: The virtual address of the stacktrace information > + * @addr_length: The length of the stacktrace information > + * @text_start: The virtual address of the text that @addr_start represents > + * @text_length: The length of teh text the also, perhaps add @flags just in case ? This allows changing the behavior without having to insert entirely new set of ops. > + * > + * This system call is used by dynamic library utilities to inform the kernel Out of curiosity: what would happen if the application chooses to invoke this system call to register sframe for the main executable ? Should it be allowed ? > + * of meta data that it loaded that can be used by the kernel to know how > + * to stack walk the given text locations. > + * > + * Currently only sframes are supported, but in the future, this may be used > + * to tell the kernel about JIT code which will most likely have a different > + * format. > + * > + * The type command may be extended and parameters may be used for other > + * purposes. "type" or "op" ? Thanks, Mathieu > + * > + * Return: 0 if successful, otherwise a negative error. > + */ > +SYSCALL_DEFINE5(stacktrace_setup, int, op, unsigned long, addr_start, > + unsigned long, addr_length, unsigned long, text_start, > + unsigned long, text_length) > +{ > + switch (op) { > + case STACKTRACE_REGISTER_SFRAME: > + return sframe_add_section(addr_start, addr_start + addr_length, > + text_start, text_start+text_length); > + case STACKTRACE_UNREGISTER_SFRAME: > + return sframe_remove_section(addr_start); > + } > + return -EINVAL; > +} -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com