Re: linux-5.10.11 build failure

[Thomas Backlund]

Den 28.1.2021 kl. 12:05, skrev Chris Clayton:
> 
> On 28/01/2021 09:34, Greg Kroah-Hartman wrote:
>> On Thu, Jan 28, 2021 at 09:17:10AM +0000, Chris Clayton wrote:
>>> Hi,
>>>
>>> Building 5.10.11 fails on my (x86-64) laptop thusly:
>>>
>>> ..
>>>
>>>   AS      arch/x86/entry/thunk_64.o
>>>    CC      arch/x86/entry/vsyscall/vsyscall_64.o
>>>    AS      arch/x86/realmode/rm/header.o
>>>    CC      arch/x86/mm/pat/set_memory.o
>>>    CC      arch/x86/events/amd/core.o
>>>    CC      arch/x86/kernel/fpu/init.o
>>>    CC      arch/x86/entry/vdso/vma.o
>>>    CC      kernel/sched/core.o
>>> arch/x86/entry/thunk_64.o: warning: objtool: missing symbol for insn at offset 0x3e
>>>
>>>    AS      arch/x86/realmode/rm/trampoline_64.o
>>> make[2]: *** [scripts/Makefile.build:360: arch/x86/entry/thunk_64.o] Error 255
>>> make[2]: *** Deleting file 'arch/x86/entry/thunk_64.o'
>>> make[2]: *** Waiting for unfinished jobs....
>>>
>>> ..
>>>
>>> Compiler is latest snapshot of gcc-10.
>>>
>>> Happy to test the fix but please cc me as I'm not subscribed
>>
>> Can you do 'git bisect' to track down the offending commit?
>>
> 
> Sure, but I'll hold that request for a while. I updated to binutils-2.36 on Monday and I'm pretty sure that is a feature
> of this build fail. I've reverted binutils to 2.35.1, and the build succeeds. Updated to 2.36 again and, surprise,
> surprise, the kernel build fails again.
> 
> I've had a glance at the binutils ML and there are all sorts of issues being reported, but it's beyond my knowledge to
> assess if this build error is related to any of them.
> 
> I'll stick with binutils-2.35.1 for the time being.
> 
>> And what exact gcc version are you using?
>>
> 
>   It's built from the 10-20210123 snapshot tarball.
> 
> I can report this to the binutils folks, but might it be better if the objtool maintainer looks at it first? The
> binutils change might just have opened the gate to a bug in objtool.
> 
>> thanks,
>>
>> greg k-h
>>
> 


AFAIK you need this in stable trees:

 From 1d489151e9f9d1647110277ff77282fe4d96d09b Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Date: Thu, 14 Jan 2021 16:14:01 -0600
Subject: [PATCH] objtool: Don't fail on missing symbol table


--
Thomas