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Date:   Sun, 16 Jun 2019 10:44:59 +0200 (CEST)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Miroslav Benes <mbenes@suse.cz>
cc:     jpoimboe@redhat.com, jikos@kernel.org, pmladek@suse.com,
        joe.lawrence@redhat.com, kamalesh@linux.vnet.ibm.com,
        live-patching@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4 1/3] stacktrace: Remove weak version of
 save_stack_trace_tsk_reliable()
In-Reply-To: <20190611141320.25359-2-mbenes@suse.cz>
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References: <20190611141320.25359-1-mbenes@suse.cz> <20190611141320.25359-2-mbenes@suse.cz>
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On Tue, 11 Jun 2019, 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@linutronix.de>
> Signed-off-by: Miroslav Benes <mbenes@suse.cz>

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>