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Date:   Tue, 22 Mar 2022 10:31:44 -0700
From:   Luis Chamberlain <mcgrof@kernel.org>
To:     Maninder Singh <maninder1.s@samsung.com>,
        Vimal Agrawal <avimalin@gmail.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.org,
        linux-kernel@vger.kernel.org, linux-modules@vger.kernel.org,
        avimalin@gmail.com, atomlin@redhat.com, keescook@chromium.org,
        ndesaulniers@google.com, rdunlap@infradead.org, void@manifault.com
Subject: Re: [PATCH 1/1 module-next] kallsyms: enhance %pS/s/b printing when
 KALLSYSMS is disabled
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References: <CGME20220316043552epcas5p29b0723b7c55a3bcc9b4d858660e45933@epcas5p2.samsung.com>
 <20220316043540.677128-1-maninder1.s@samsung.com>
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On Wed, Mar 16, 2022 at 10:05:40AM +0530, Maninder Singh wrote:
> print module information when KALLSYMS is disabled.
> 
> No change for %pB, as it needs to know symbol name to adjust address
> value which can't be done without KALLSYMS.
> 
> (A) 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]
> 
> (B) original output without KALLSYMS:
> [12.487424] ps 0xffff800000eb008c
> [12.487598] pS 0xffff800000eb008c
> [12.487723] pSb 0xffff800000eb008c
> [12.487850] pB 0xffff800000eb008c
> [12.487967] pBb 0xffff800000eb008c
> 
> (C) With patched kernel
> with KALLYSMS:
> [41.974576] ps function_1 [crash]
> [41.975173] pS function_1+0x4/0x2c [crash]
> [41.975386] pSb function_1+0x4/0x2c [crash a8b20caaec9635b316cf4812f6b55598fe2b7cee]
> [41.975879] pB function_1+0x4/0x2c [crash]
> [41.976076] pBb function_1+0x4/0x2c [crash a8b20caaec9635b316cf4812f6b55598fe2b7cee]
> 
> without KALLSYMS:
> [9.624152] ps 0xffff800001bd008c [crash]	// similar to original, no changes
> [9.624548] pS 0x(____ptrval____)+0x8c [crash]   // base address hashed and offset is without hash
> [9.624847] pSb 0x(____ptrval____)+0x8c [crash a8b20caaec9635b316cf4812f6b55598fe2b7cee]
> [9.625388] pB 0x(____ptrval____)+0x8c [crash]
> [9.625594] pBb 0x(____ptrval____)+0x8c [crash a8b20caaec9635b316cf4812f6b55598fe2b7cee]
> 
> with disable hashing:
> [8.563916] ps 0xffff800000f2008c [crash]
> [8.564574] pS 0xffff800000f20000+0x8c [crash]
> [8.564749] pSb 0xffff800000f20000+0x8c [crash 3423a8993a7033fb79e5add14bf9d8d6b56330ca]
> [8.565008] pB 0xffff800000f20000+0x8c [crash]
> [8.565154] pBb 0xffff800000f20000+0x8c [crash 3423a8993a7033fb79e5add14bf9d8d6b56330ca]
> 
> 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>

I've pushed a lot of queued code into modules-testing (not modules-next
yet) [0] please base your changes on that in a new iteration as that is what
things look like now.

Vimal might be interested in your work too and you might be interested
in his patch too [1].

[0] https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git/log/?h=modules-testing
[1] https://lkml.kernel.org/r/CALkUMdRO+JAF_Dw3Q-mHOxvt7uM6gVDNGAA3OMeCUpnSvi7_Pg@mail.gmail.com

  Luis