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Date:   Fri, 17 Jul 2020 11:04:52 +0200 (CEST)
From:   Miroslav Benes <mbenes@suse.cz>
To:     Mark Brown <broonie@kernel.org>
cc:     Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Heiko Carstens <hca@linux.ibm.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Borislav Petkov <bp@alien8.de>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        Ingo Molnar <mingo@kernel.org>,
        Jiri Slaby <jirislaby@kernel.org>, x86@kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-s390@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/3] stacktrace: Remove reliable argument from
 arch_stack_walk() callback
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References: <20200715202821.12220-1-broonie@kernel.org> <20200715202821.12220-2-broonie@kernel.org>
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On Wed, 15 Jul 2020, Mark Brown wrote:

> Currently the callback passed to arch_stack_walk() has an argument called
> reliable passed to it to indicate if the stack entry is reliable, a comment
> says that this is used by some printk() consumers. However in the current
> kernel none of the arch_stack_walk() implementations ever set this flag to
> true and the only callback implementation we have is in the generic
> stacktrace code which ignores the flag. It therefore appears that this
> flag is redundant so we can simplify and clarify things by removing it.

Correct. I dug around and it seems it was the case even when it was 
introduced. So I wonder about the comment. I don't remember the details, 
maybe Thomas or someone else does. But the patch looks correct.

Miroslav