linux-kernel - Re: [PATCH 1/2 v2] kdump: add the vmcoreinfo documentation

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <72c311b4-1946-0bcf-54d9-9fcd7f6e630c@redhat.com>
Date:   Wed, 5 Dec 2018 22:21:46 +0800
From:   lijiang <lijiang@...hat.com>
To:     Dave Young <dyoung@...hat.com>
Cc:     Borislav Petkov <bp@...en8.de>, linux-kernel@...r.kernel.org,
        kexec@...ts.infradead.org, tglx@...utronix.de, mingo@...hat.com,
        x86@...nel.org, akpm@...ux-foundation.org, bhe@...hat.com,
        Jonathan Corbet <corbet@....net>, linux-doc@...r.kernel.org,
        Kazuhito Hagio <k-hagio@...jp.nec.com>
Subject: Re: [PATCH 1/2 v2] kdump: add the vmcoreinfo documentation

在 2018年12月05日 18:16, Dave Young 写道:
>>>> +init_uts_ns
>>>> +===========
>>>> +This is the UTS namespace, which is used to isolate two specific elements
>>>> +of the system that relate to the uname system call. The UTS namespace is
>>>> +named after the data structure used to store information returned by the
>>>> +uname system call.
>>>
>>> Those non-obvious exports should also have a short explanation why
>>> they're part of VMCOREINFO.
>>>
>>>> +
>>>> +node_online_map
>>>> +===============
>>>> +It is a macro definition, actually it is an arrary node_states[N_ONLINE],
>>>> +and it represents the set of online node in a system, one bit position
>>>> +per node number.
>>>
>>> Ditto.
>>>
>>> So yeah, people can find out what those things are but I think it is
>>> more important to state here *why* they're part of VMCOREINFO and how
>>> they're used and why they're exported.
>>>
>>
>> This is a good question.
>>
>> For these two *why*, it should be easy to understand. Because user-space tools
>> need to know basic information, such as the symbol values, field offset, structure
>> size, etc. Otherwise, these tools won't know how to analyze the memory of the crash
>> kernel.
>>
>> For the second question 'how they are used', we can get the answer from user-space
>> tools, such as makedumpfile, crash tools. Therefore, it may not need to explain any
>> more in kernel document. On the other hand, if we must put these contents into kernel
>> document, i have to say, that would be a hard task.
> 
> It should be a good chance to learn how makedumpfile works :),  Maybe it is
> hard to get *all* of them, but it would be good to dig and find the
> thing you can find then explain it.  And leave those *unknown* part as
> FIXME or TODO, people can add description later. 
> 

Thank you, Dave.

It looks like a good idea.


Regards,
Lianbo

> Added Kazu in cc as well..
> > Thanks
> Dave
>