Re: [PATCH v4 1/3] stacktrace: Remove weak version of save_stack_trace_tsk_reliable()

From: Kamalesh Babulal
Date: Wed Jun 12 2019 - 09:46:08 EST

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>