* Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx> wrote: > On Fri, 13 Nov, at 10:22:10AM, Ingo Molnar wrote: > > > > * Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx> wrote: > > > > > +We map EFI runtime services in the efi_pgd PGD in the virtual range of > > > +64Gb (arbitrarily set, can be raised if needed). The mappings are not > > > +part of any other kernel PGD and are only available during EFI runtime > > > +calls. > > > > Is that virtual address range 0-64Gb, i.e.: > > > > 0x00000000.00000000 - 0x00000010.00000000 > > > > or is it somewhere else? > > You've snipped the patch hunk that gives the address range used, > > diff --git a/Documentation/x86/x86_64/mm.txt > b/Documentation/x86/x86_64/mm.txt > index 05712ac83e38..a9885bb1ac22 100644 > --- a/Documentation/x86/x86_64/mm.txt > +++ b/Documentation/x86/x86_64/mm.txt > @@ -16,6 +16,8 @@ ffffec0000000000 - fffffc0000000000 (=44 bits) kasan > shadow memory (16TB) > ... unused hole ... > ffffff0000000000 - ffffff7fffffffff (=39 bits) %esp fixup stacks > ... unused hole ... > +ffffffef00000000 - ffffffff00000000 (=64 GB) EFI region mapping space > +... unused hole ... > ffffffff80000000 - ffffffffa0000000 (=512 MB) kernel text mapping, > from phys 0 > ffffffffa0000000 - ffffffffff5fffff (=1525 MB) module mapping space > ffffffffff600000 - ffffffffffdfffff (=8 MB) vsyscalls Ah yes - but then the text is misleading, what does 'in the virtual range of 64Gb' mean? A virtual memory range is a specific range of addresses - like in the table you extended. A better phrasing would be something like: We map EFI runtime services in the 'efi_pgd' PGD in a 64Gb large virtual memory window (this size is arbitrary, it can be raised later if needed). Agreed? Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
