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Subject: Re: [PATCH] panic: Avoid dump_stack() twice
To:     Kefeng Wang <wangkefeng.wang@huawei.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org
References: <20201113054747.177919-1-wangkefeng.wang@huawei.com>
From:   Alexey Kardashevskiy <aik@ozlabs.ru>
Message-ID: <40b1b70f-16d9-01c4-c045-508cde14f4c2@ozlabs.ru>
Date:   Fri, 13 Nov 2020 17:39:35 +1100
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Fixed already

https://ozlabs.org/~akpm/mmots/broken-out/panic-dont-dump-stack-twice-on-warn.patch

Sorry for breaking this :(


On 13/11/2020 16:47, Kefeng Wang wrote:
> stacktrace will be dumped twice on ARM64 after commit 3f388f28639f
> ("panic: dump registers on panic_on_warn"), will not dump_stack
> when no regs as before.
> 
> Fixes: 3f388f28639f ("panic: dump registers on panic_on_warn")
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> ---
>   kernel/panic.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/kernel/panic.c b/kernel/panic.c
> index 396142ee43fd..332736a72a58 100644
> --- a/kernel/panic.c
> +++ b/kernel/panic.c
> @@ -605,7 +605,8 @@ void __warn(const char *file, int line, void *caller, unsigned taint,
>   		panic("panic_on_warn set ...\n");
>   	}
>   
> -	dump_stack();
> +	if (!regs)
> +		dump_stack();
>   
>   	print_irqtrace_events(current);
>   
> 

-- 
Alexey