On Tue, Jun 11, 2019 at 04:13:18PM +0200, Miroslav Benes wrote: > Recent rework of stack trace infrastructure introduced a new set of > helpers for common stack trace operations (commit e9b98e162aa5 > ("stacktrace: Provide helpers for common stack trace operations") and > related). As a result, save_stack_trace_tsk_reliable() is not directly > called anywhere. Livepatch, currently the only user of the reliable > stack trace feature, now calls stack_trace_save_tsk_reliable(). > > When CONFIG_HAVE_RELIABLE_STACKTRACE is set and depending on > CONFIG_ARCH_STACKWALK, stack_trace_save_tsk_reliable() calls either > arch_stack_walk_reliable() or mentioned save_stack_trace_tsk_reliable(). > x86_64 defines the former, ppc64le the latter. All other architectures > do not have HAVE_RELIABLE_STACKTRACE and include/linux/stacktrace.h > defines -ENOSYS returning version for them. > > In short, stack_trace_save_tsk_reliable() returning -ENOSYS defined in > include/linux/stacktrace.h serves the same purpose as the old weak > version of save_stack_trace_tsk_reliable() which is therefore no longer > needed. > > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Signed-off-by: Miroslav Benes <mbenes@xxxxxxx> Reviewed-by: Kamalesh Babulal <kamalesh@xxxxxxxxxxxxxxxxxx>