On 01/17, Masami Hiramatsu wrote: > > On Tue, 14 Jan 2025 15:21:29 +0100 > Jiri Olsa <olsajiri@xxxxxxxxx> wrote: > > > On Tue, Jan 14, 2025 at 12:21:07PM +0100, Oleg Nesterov wrote: > > > > > > But please not that the uretprobed function can return any value > > > including -ENOSYS, and this is what sys_uretprobe() has to return. > > > > right, uretprobe syscall returns value of the uretprobed function, > > so we can't use any reserved value > > We can make uretprobe (entry) fail if the return value is one of > errno or NULL, because it *knows* what the return value here. I fail to understand... Could you spell please? But whatever you meant, I don't think it is right, sorry.. please correct me. "it *knows*". Who it? How can it know??? I'd say "it" can't know, but probably I missed your point. Not to mention it doesn't really matter. It is not safe to even try to do movq $__NR_uretprobe, %rax syscall if the probed task has seccomp filters. Oleg.
