On Fri, 10 Apr 2020 at 16:02, Dave Young <dyoung@xxxxxxxxxx> wrote:
>
> On 04/10/20 at 09:56pm, Dave Young wrote:
> > On 04/10/20 at 09:43am, Ard Biesheuvel wrote:
> > > Commit
> > >
> > > 0a67361dcdaa29 ("efi/x86: Remove runtime table address from kexec EFI setup data")
> > >
> > > removed the code that retrieves the non-remapped UEFI runtime services
> > > pointer from the data structure provided by kexec, as it was never really
> > > needed on the kexec boot path: mapping the runtime services table at its
> > > non-remapped address is only needed when calling SetVirtualAddressMap(),
> > > which never happens during a kexec boot in the first place.
> > >
> > > However, dropping the 'runtime' member from struct efi_setup_data was a
> > > mistake. That struct is shared ABI between the kernel and the kexec tooling
> > > for x86, and so we cannot simply change its layout. So let's put back the
> > > removed field, but call it 'unused' to reflect the fact that we never look
> > > at its contents. While at it, add a comment to remind our future selves
> > > that the layout is external ABI.
> > >
> > > Reported-by: Theodore Ts'o <tytso@xxxxxxx>
> > > Tested-by: Theodore Ts'o <tytso@xxxxxxx>
> > > Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
> > > ---
> > >
> > > Ingo, Thomas, Boris: I sent out my efi-urgent pull request just yesterday,
> > > so please take this directly into tip:efi/urgent - no need to wait for the
> > > next batch.
> > >
> > > arch/x86/include/asm/efi.h | 2 ++
> > > 1 file changed, 2 insertions(+)
> > >
> > > diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
> > > index 781170d36f50..96044c8d8600 100644
> > > --- a/arch/x86/include/asm/efi.h
> > > +++ b/arch/x86/include/asm/efi.h
> > > @@ -178,8 +178,10 @@ extern void efi_free_boot_services(void);
> > > extern pgd_t * __init efi_uv1_memmap_phys_prolog(void);
> > > extern void __init efi_uv1_memmap_phys_epilog(pgd_t *save_pgd);
> > >
> > > +/* kexec external ABI */
> > > struct efi_setup_data {
> > > u64 fw_vendor;
> > > + u64 unused;
> > > u64 tables;
> > > u64 smbios;
> > > u64 reserved[8];
> > > --
> > > 2.17.1
> > >
> >
> > Ah, replied too quick in another mail. I just cced kexec list again.
> >
> > Thanks for the fix:
> >
> > Reviewed-by: Dave Young <dyoung@xxxxxxxxxx>
> >
>
Thanks Dave
> BTW, a fixes tag is good to have..
>
I usually omit those for patches that fix bugs that were introduced in
the current cycle.
