On Thu, Jul 05, 2018 at 12:02:15PM +0100, James Morse wrote: > On 05/07/18 10:43, AKASHI Takahiro wrote: > > On Wed, Jul 04, 2018 at 08:49:32PM +0200, Ard Biesheuvel wrote: > >> On 4 July 2018 at 19:06, Will Deacon <will.deacon@xxxxxxx> wrote: > >>> On Tue, Jun 19, 2018 at 03:44:23PM +0900, AKASHI Takahiro wrote: > >>>> Since arm_enter_runtime_services() was modified to always create a virtual > >>>> mapping of UEFI memory map in the previous patch, it is now renamed to > >>>> efi_enter_virtual_mode() and called earlier before acpi_load_tables() > >>>> in acpi_early_init(). > >>>> > >>>> This will allow us to use UEFI memory map in acpi_os_ioremap() to create > >>>> mappings of ACPI tables using memory attributes described in UEFI memory > >>>> map. > > >>> Hmm, this is ugly as hell. Is there nothing else we can piggy-back off? > >>> It's also fairly jarring that, on x86, efi_enter_virtual_mode() is called > >>> a few lines later, *after* acpi_early_init() has been called. > > >> Currently, there is a gap where we have already torn down the early > >> mapping and haven't created the definitive mapping of the UEFI memory > >> map. There are other reasons why this is an issue, and I recently > >> proposed [0] myself to address one of them > > >> Akashi-san, could you please confirm whether the patch below would be > >> sufficient for you? Apologies for going back and forth on this, but I > >> agree with Will that we should try to avoid warts like the one above > >> in generic code. > >> > >> [0] https://marc.info/?l=linux-efi&m=152930773507524&w=2 > > > > I think that this patch will also work. > > Please drop my patch#2 and #3 if you want to pick up my patchset, Will. > > Patch 2 is what changes arm_enable_runtime_services() to map the efi memory map > before bailing out due to efi=noruntime. > > Without it, 'efi=noruntime' means no-acpi-tables. So it sounds like we want patch 2. Akashi, given that this series is only four patches, please can you send out a v3 with the stuff that should be reviewed and merged? Otherwise, there's a real risk we end up with breakage that goes unnoticed initially. Thanks, Will _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
