From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sasha Levin <levinsasha928@gmail.com>
Subject: Re: [PATCH] kvm tools: Make the whole guest memory mergeable
Date: Fri, 16 Dec 2011 11:46:49 +0200
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To: Zang Hongyong <zanghongyong@huawei.com>
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On Fri, 2011-12-16 at 17:33 +0800, Zang Hongyong wrote:
> > Do you see an issue with increasing kvm->ram_size?
> >
> Yes, it will cause some problems after simply increase the kvm->ram_size.
> For examples:
> In kvm__init_ram() code we use kvm->ram_size to calculate the size of
> the second
> RAM range from 4GB to the end of RAM (phys_size = kvm->ram_size -
> phys_size;),
> so after increase the kvm->ram_size, it will goes wrong.
> This problem also happens in e820_setup() code and load_bzimage() code. 

Yup, but fixing it is much easier than having two different sizes of the same thing.

For example, the fix for the problem in kvm__init_ram() (and e820_setup()) would be:

@@ -112,7 +112,7 @@ void kvm__init_ram(struct kvm *kvm)
                /* Second RAM range from 4GB to the end of RAM: */
 
                phys_start = 0x100000000ULL;
-               phys_size  = kvm->ram_size - phys_size;
+               phys_size  = kvm->ram_size - phys_start;
                host_mem   = kvm->ram_start + phys_start;
 
                kvm__register_mem(kvm, phys_start, phys_size, host_mem);

I basically want one memory map with one size which includes *everything*, even if that memory map includes a gap in the middle I still want the total size to include that gap.

btw, what problem do you see in load_bzimage()?

-- 

Sasha.