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Date:   Mon, 28 Feb 2022 07:35:31 -0800
From:   Luis Chamberlain <mcgrof@kernel.org>
To:     Maninder Singh <maninder1.s@samsung.com>
Cc:     pmladek@suse.com, rostedt@goodmis.org, senozhatsky@chromium.org,
        andriy.shevchenko@linux.intel.com, linux@rasmusvillemoes.dk,
        akpm@linux-foundation.org, wangkefeng.wang@huawei.com,
        v.narang@samsung.com, swboyd@chromium.org, ojeda@kernel.or,
        linux-kernel@vger.kernel.org, linux-modules@vger.kernel.org,
        avimalin@gmail.com, atomlin@redhat.com
Subject: Re: [PATCH 1/1] kallsyms: enhance %pS/s/b printing when KALLSYSMS is
 disabled
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References: <CGME20220228053457epcas5p1dac3fced39d1594f8fdfc5e64e23ac73@epcas5p1.samsung.com>
 <20220228053447.1584704-1-maninder1.s@samsung.com>
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On Mon, Feb 28, 2022 at 11:04:47AM +0530, Maninder Singh wrote:
> with commit '82b37e632513 ("kallsyms: print module name in %ps/S
> case when KALLSYMS is disabled"), module name printing was enhanced.
> 
> As per suggestion from Petr Mladek <pmladek@suse.com>, covering
> other flavours also to print build id also.
> 
> for %pB no change as it needs to know symbol name to adjust address
> value which can't be done without KALLSYMS.
> 
> original output with KALLSYMS:
> [8.842129] ps function_1 [crash]
> [8.842735] pS function_1+0x4/0x2c [crash]
> [8.842890] pSb function_1+0x4/0x2c [crash b367e79021b9f3b0172f9a36d4261c1f528ca1b3]
> [8.843175] pB function_1+0x4/0x2c [crash]
> [8.843362] pBb function_1+0x4/0x2c [crash b367e79021b9f3b0172f9a36d4261c1f528ca1b3]
> 
> original output without KALLSYMS:
> [12.487424] ps 0xffff800000eb008c
> [12.487598] pS 0xffff800000eb008c
> [12.487723] pSb 0xffff800000eb008c
> [12.487850] pB 0xffff800000eb008c
> [12.487967] pBb 0xffff800000eb008c
> 
> With patched kernel without KALLSYMS:
> [9.205207] ps 0xffff800000eb008c [crash]
> [9.205564] pS 0xffff800000eb0000+0x8c [crash]
> [9.205757] pSb 0xffff800000eb0000+0x8c [crash b367e79021b9f3b0172f9a36d4261c1f528ca1b3]
> [9.206066] pB 0xffff800000eb0000+0x8c [crash]
> [9.206257] pBb 0xffff800000eb0000+0x8c [crash b367e79021b9f3b0172f9a36d4261c1f528ca1b3]
> 
> Suggested-by: Petr Mladek <pmladek@suse.com>
> Co-developed-by: Vaneet Narang <v.narang@samsung.com>
> Signed-off-by: Vaneet Narang <v.narang@samsung.com>
> Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
> ---
> earlier discussion: https://lkml.org/lkml/2022/2/10/185
> 
>  include/linux/kallsyms.h | 27 --------------
>  kernel/module.c          |  4 +--

See Aaron's work which you'll need to base your work on:

https://lkml.kernel.org/r/20220222141303.1392190-1-atomlin@redhat.com

Soon Aaron will post a v9.

  Luis