Re: [PATCH 0/2] Tentative fix for the divide-by-zero on score/paris/..

Guenter Roeck
2015-04-16T01:43:27Z

On 04/15/2015 02:19 PM, Quentin Casasnovas wrote:
> On Wed, Apr 15, 2015 at 06:26:58AM -0700, Guenter Roeck wrote:
>> On 04/15/2015 01:54 AM, Quentin Casasnovas wrote:
>>> The following two patches might (hopefully) fix the build breakage on score
>>> and some other architectures. I've checked the new __ex_table checker
>>> still works on x86-64 with them (it still detects an entry pointing to
>>> .altinstr_rplacement) and they should apply cleanly on top of Rusty's
>>> module-next branch.
>>>
>>> Thanks to Guenter for the bug analysis and sorry again for the breakage.
>>>
>>> Let me know if this makes things better..
>>>
>>
>> the crash is fixed, but now I get
>>
>> FATAL: The relocation at __ex_table+0x4 references
>> section "" which is not executable, IOW
>> the kernel will fault if it ever tries to
>> jump to it. Something is seriously wrong
>> and should be fixed.
>>
>> for parisc:defconfig,
>>
>> FATAL: The relocation at __ex_table+0x634 references
>> section "__ex_table" which is not executable, IOW
>> the kernel will fault if it ever tries to
>> jump to it. Something is seriously wrong
>> and should be fixed.
>>
>> for score:allnoconfig, and
>>
>> FATAL: The relocation at __ex_table+0x8 references
>> section "" which is not executable, IOW
>> it is not possible for the kernel to fault
>> at that address. Something is seriously wrong
>> and should be fixed.
>>
>> for mn10300:defconfig.
>>
>> While I agree that those should get fixed (if they are real problems,
>> especially the ones for parisc and mn10300), I don't think it is
>> a good idea to fail the build because of it.
>>
>> Note that I did find the problem in the score build; that was a real bug.
>> I don't know what may be wrong with the others.
>>
>
> The attached patch fixes the build failures on parisc and mn10300 on my
> defconfig build and should apply cleanly on top of the previous two.
>
> I'm not able to download the score cross toolchain for the moment but will
> do tomorrow. Guenter, may I ask if there were any other problems than the
> one you fixed in string.S there?
>

For

>From 2e9abac9cbde18af48951c54d52c9c515f9883a7 Mon Sep 17 00:00:00 2001
From: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Date: Wed, 15 Apr 2015 22:39:50 +0200
Subject: [PATCH] modpost: do not try to match the SHT_NUL section.

Tested-by: Guenter Roeck <linux@roeck-us.net>

Guenter