Re: [PATCHv2] x86/boot/KASLR: skip the specified crashkernel reserved region

[Baoquan He]

On 03/29/19 at 01:45pm, Pingfan Liu wrote:
> On Fri, Mar 22, 2019 at 4:34 PM Baoquan He <bhe@xxxxxxxxxx> wrote:
> >
> > On 03/22/19 at 03:52pm, Baoquan He wrote:
> > > On 03/22/19 at 03:43pm, Pingfan Liu wrote:
> > > > > > +/* parse crashkernel=x@y option */
> > > > > > +static void mem_avoid_crashkernel_simple(char *option)
> > > > >
> > > > > Chao ever mentioned this, I want to ask again, why does it has to be
> > > > > xxx_simple()?
> > > > >
> > > > Seems that I had replied Chao's question in another email. The naming
> > > > follows the function parse_crashkernel_simple(), as the notes above
> > >                        ~~~~~~~~~~~~~~~~~~~~~~~~
> > >
> > > Sorry, I don't get.  typo?
> >
> > OK, I misunderstood it. We do have parse_crashkernel_simple() to handle
> > crashkernel=size[@offset] case, to differente with other complicated
> > cases, like crashkernel=size,[high|low],
> >
> > Then I am fine with this naming. Soryy about the noise.
> >
> > By the way, do you think if we should take care of this case:
> > crashkernel=<range1>:<size1>[,<range2>:<size2>,...][@offset]
> >
> > It can also specify @offset. Not sure if it's too complicated, you may
> > have a investigation.
> >
> In this case, kernel should get the total memory size info. So
> process_e820_entries() or process_efi_entries() should be called
> twice. One before handle_mem_options(), so crashkernel can evaluate
> the reserved size. It is doable, and what is your opinion about the

You mean calling process_e820_entries to calculate the RAM size in
system? I may not do like that, please check what __find_max_addr() is
doing. Did I get it?