Hey,
So, as I promised in other thread I am sending more info about my investigation
related to low memory allocation for trampoline and other early boot data.
Starting from the beginning it looks that there are "soft" limits enforced
in BIOS early boot code looking for usable low memory region.
>>> On 14.09.16 at 10:23, wrote:
> Starting from the beginning it looks that there are "soft" limits enforced
> in BIOS early boot code looking for usable low memory region. Hight limit
> is set at 640 KiB and low at 256 KiB. This means that if a value from a given
> source which describes low mem
On Fri, Sep 16, 2016 at 06:15:10AM -0600, Jan Beulich wrote:
> >>> On 14.09.16 at 10:23, wrote:
> > Starting from the beginning it looks that there are "soft" limits enforced
> > in BIOS early boot code looking for usable low memory region. Hight limit
> > is set at 640 KiB and low at 256 KiB. Thi
>>> On 20.09.16 at 14:11, wrote:
> On Fri, Sep 16, 2016 at 06:15:10AM -0600, Jan Beulich wrote:
>> >>> On 14.09.16 at 10:23, wrote:
>> > Additionally, my investigation has shown that there are no bound checks in
>> > low memory allocation machinery for trampoline (by the way, in BIOS path we
>> >
On Tue, Sep 20, 2016 at 07:23:06AM -0600, Jan Beulich wrote:
> >>> On 20.09.16 at 14:11, wrote:
> > On Fri, Sep 16, 2016 at 06:15:10AM -0600, Jan Beulich wrote:
> >> >>> On 14.09.16 at 10:23, wrote:
> >> > Additionally, my investigation has shown that there are no bound checks
> >> > in
> >> > l
>>> On 20.09.16 at 20:26, wrote:
> However, if you care I would ask why do you use
> 1 MiB limit instead of 640 KiB in xen/arch/x86/efi/efi-boot.h? I do not
> say this is huge mistake but I am curious why not 640 KiB? I suppose that
> there was a reason for it but I cannot find anything about that