Source-Changes-D archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: CVS commit: src/sys/arch/amd64/amd64



On 22.04.2018 07:46, Maxime Villard wrote:
> Le 22/04/2018 à 01:25, Joerg Sonnenberger a écrit :
>> Module Name:    src
>> Committed By:    joerg
>> Date:        Sat Apr 21 23:25:01 UTC 2018
>>
>> Modified Files:
>>     src/sys/arch/amd64/amd64: locore.S
>>
>> Log Message:
>> Do not use movq for loading arbitrary 64bit immediates. The ISA
>> restricts it to 32bit immediates.
>>
>>
>> To generate a diff of this commit:
>> cvs rdiff -u -r1.163 -r1.164 src/sys/arch/amd64/amd64/locore.S
>>
>> Please note that diffs are not public domain; they are subject to the
>> copyright notices on the relevant files.
> 
> Mmh. Is there a compiler where this makes a difference? On NetBSD/GGG it
> doesn't (because if it did, SVS would never have worked), but I see that
> on MacOS the instruction indeed makes a difference, the encoding becomes:
> 
>     movq    0x0, %rax
> 
> Which is obviously not what we expect.
> 
> Is this the problem you were having a few weeks ago? That is to say, the
> kernel that was crashing at boot time, did you compile it on another
> system/compiler that generated a "movq 0x0,%rax"?
> 
> Anyway your change seems correct.
> 
> Thanks,
> Maxime

There are reports that the SVS kernel built by Clang doesn't work.

Attachment: signature.asc
Description: OpenPGP digital signature



Home | Main Index | Thread Index | Old Index