Re: [PATCH v3 3/3] printk: use the lockless ringbuffer

[lijiang]

å 2020å07æ02æ 17:02, John Ogness åé:
> On 2020-07-02, lijiang <lijiang@xxxxxxxxxx> wrote:
>> About the VMCOREINFO part, I made some tests based on the kernel patch
>> v3, the makedumpfile and crash-utility can work as expected with your
>> patch(userspace patch), but, unfortunately, the vmcore-dmesg(kexec-tools)
>> can't correctly read the printk ring buffer information, and get the
>> following error:
>>
>> "Missing the log_buf symbol"
>>
>> The kexec-tools(vmcore-dmesg) should also have a similar patch, just like
>> in the makedumpfile and crash-utility.
> 
> Yes, a patch for this is needed (as well as for any other related
> software floating around the internet).
> 
> I have no RFC patches for vmcore-dmesg. Looking at the code, I think it
> would be quite straight forward to port the makedumpfile patch. I will

Yes, it should be a similar patch.

> try to make some time for this.
> 
That would be nice. Thank you, John Ogness.

> I do not want to patch any other software for this. I think with 3
> examples (crash, makedumpfile, vmcore-dmesg), others should be able to

It's good enough to have the patch for the makedumpfile, crash and vmcore-dmesg,
which can ensure the kdump(userspace) work well.

Thanks.
Lianbo

> implement the changes to their software without needing my help.
> 
> John Ogness
>