On 09/20/13 at 03:29pm, Dave Young wrote: > On 09/19/13 at 04:54pm, Borislav Petkov wrote: > > From: Borislav Petkov <bp@xxxxxxx> > > > > Hi all, > > > > here's finally a new version of the runtime services VA mapping patchset > > which hopefully implements hpa's idea of statically mapping EFI runtime > > regions in a top-down manner starting at -4Gb virtual. > > > > We're also using a different pagetable so as not to pollute kernel > > address space. For that, we switch to that table before doing an EFI > > call, and afterwards we switch back to the previous one. > > > > To the patches: > > > > 1-2 are simple cleanups which Matt probably can take now > > > > 3-10 add the machinery to map regions into an arbitrary PGD. Those I've > > split deliberately into very small bites so that they can be reviewed > > more thoroughly and easily for my pagetable skills are pretty basic. > > > > 11 is the actual patch which implements that mapping so that we can use > > runtime services in kexec (which is the whole reason for this fuss :)) > > > > So please take a long hard look at those, hammer on them on your > > boxes and let me know. They boot fine on my Dell UEFI box and in OVMF > > (obviously :)). > > Thanks for your update! > > Just tested this series, for 1st kernel It boots ok in qemu+ovmf. But it immediately > reboot on my Thinkpad T420. Unfortunately there's no way to debug this > very early problem because there's no serial port also earlyprintk does > not work for efi boot. No usb debug as well on this machine. I will test > it when I go back to work after the china holiday. Actually the ovmf testing is "qemu-system-x86_64 -kernel ", boot from grub fails as well. Nothing printed on serial. I guess '-kernel' is using efi stub to boot? > > OTOH, for 2nd kernel testing because kexec tools does not fill efi_info[] > in bootparam so kernel will disable efi, also it pass acpi_rsdp pointer > automaticlly to make 2nd kernel boot ok. > > I tested with a user space patch which copy efi_info from 1st kernel to > bootparams, as I said previously this is not enough because several fields > in systab, fw_vendor, runtime and tables are converted to virtual address > but in kernel efi init function they are assumed physical addresses. Thus > we need save these physical address. I have a patch to save them and pass > them to 2nd kernel in bootparams. > Since the mapping are same, I wonder if we can calculate the physical > address from virtual address. Idea? > > Another concern is that is it safe for i386 efi boot? > -- 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
