On Tue, Mar 15, 2022 at 09:21:00PM +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 <redacted>
Signed-off-by: Vaneet Narang <redacted>
Signed-off-by: Maninder Singh <redacted>
---
commit id 'kallsyms: print module name in %ps/S case when KALLSYMS is disabled'
	needs to be removed from mm(linux-next) tree, current change is
	with ignorance of this commit. I was not sure how to send patch, with 2 patches
	consisting reversal commit also, or current approach is correct.

v1->v2: hash base address of module, change *fmt to fmt[0] and removed
        copy paste.
v2->v3: fixed review comments from Andy Shevchenko [off-list ref]

 include/linux/kallsyms.h |  2 +
 include/linux/module.h   | 20 ++++++++++
 kernel/kallsyms.c        | 27 +++++++------
 kernel/module.c          |  4 +-
 lib/vsprintf.c           | 85 ++++++++++++++++++++++++++++++++++------

Hey Maninder, thanks for your patch!

Since this touches kernel/module.c and include/linux/module.h I'd prefer
this go through modules-next [0], and as you will see that's a different
world right now. I also have a set of at least 2 other patch sets to
merge there before yours.

Also, what is on modules-next is not intended to go to Linus for the
next merge window as the changes there got merged only late, and I want
at least 2 months of testing on linux-newt before any pull requiest is
sent to Linus.

Can you rebase to modules-next? I can evaluate the patches then for
integration there once the other stuff gets merged into that tree too.

[0] https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git/log/?h=modules-next

  Luis