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

[John Ogness]

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
try to make some time for this.

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
implement the changes to their software without needing my help.

John Ogness