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Date:   Mon, 26 Apr 2021 13:04:28 +0200
From:   Petr Mladek <pmladek@suse.com>
To:     Stephen Boyd <swboyd@chromium.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, Jiri Olsa <jolsa@kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Jessica Yu <jeyu@kernel.org>,
        Evan Green <evgreen@chromium.org>,
        Hsin-Yi Wang <hsinyi@chromium.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Matthew Wilcox <willy@infradead.org>
Subject: Re: [PATCH v5 04/13] dump_stack: Add vmlinux build ID to stack traces
Message-ID: <YIaePJGgD+FEQAUF@alley>
References: <20210420215003.3510247-1-swboyd@chromium.org>
 <20210420215003.3510247-5-swboyd@chromium.org>
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On Tue 2021-04-20 14:49:54, Stephen Boyd wrote:
> Add the running kernel's build ID[1] to the stacktrace information
> header.  This makes it simpler for developers to locate the vmlinux with
> full debuginfo for a particular kernel stacktrace. Combined with
> scripts/decode_stracktrace.sh, a developer can download the correct
> vmlinux from a debuginfod[2] server and find the exact file and line
> number for the functions plus offsets in a stacktrace.
> 
> diff --git a/include/linux/buildid.h b/include/linux/buildid.h
> index f375900cf9ed..3b7a0ff4642f 100644
> --- a/include/linux/buildid.h
> +++ b/include/linux/buildid.h
> @@ -10,7 +10,11 @@ int build_id_parse(struct vm_area_struct *vma, unsigned char *build_id,
>  		   __u32 *size);
>  int build_id_parse_buf(const void *buf, unsigned char *build_id, u32 buf_size);
>  
> +#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) || IS_ENABLED(CONFIG_CRASH_CORE)

Why is this enabled for CONFIG_CRASH_CORE, please?

Is some crash_core code going to printk it id even when
CONFIG_STACKTRACE_BUILD_ID is disabled?

Anyway, this condition should be added in the patch when a code is
really going to depend on it. Or the intention should be explained
in the commit message at least.


>  extern unsigned char vmlinux_build_id[BUILD_ID_SIZE_MAX];
>  void init_vmlinux_build_id(void);
> +#else
> +static inline void init_vmlinux_build_id(void) { }
> +#endif

Otherwise, the patch looks good to me.

Best Regards,
Petr