Re: [PATCH] kdump: add default crashkernel reserve kernel config options

From: Dave Young
Date: Thu May 24 2018 - 03:03:37 EST


> > > Instead of setting aside a significant chunk of memory nobody can use,
> > > [...] reserve a significant chunk of memory that the kernel is prevented
> > > from using [...], but applications are free to use it.
> >
> > That works great, because user space pages are filtered out in the
> > common case, so they can be used freely by the panic kernel.
>
> Good suggestion. I have been reading that posts already at the same time before I saw
> this reply from you :)
>
> That could be a good idea and worth to discuss more. I cced Hari
> already in the thread. Hari, is it possible for you to extend your
> idea to general use, ie. shared by both kdump and fadump? Anyway I
> think that is another topic we can discuss separately.

BTW, I remember we had some Red hat internal discussion about CMA previously
there is a problem, that is we have crashkernel=,high for reserving high
memory and ,low for low memory, we were not sure if CMA can handle this
case.

Thanks
Dave
Thanks
Dave