| Message ID | 1407823822-23829-4-git-send-email-dyoung@redhat.com |
|---|---|
| State | Rejected |
| Headers | show |
On Tue, 12 Aug, at 02:10:21PM, Dave Young wrote: > If enter virtual mode failed due to some reason other than the efi call > the EFI_RUNTIME_SERVICES bit in efi.flags should be cleared thus users > of efi runtime services can check the bit and handle the case instead of > assume efi runtime is ok. > > Per Matt, if efi call SetVirtualAddressMap fails we will be not sure it's safe > to make any assumptions about the state of the system. so kernel panics instead > of clears EFI_RUNTIME_SERVICES bit. > > Signed-off-by: Dave Young <dyoung@redhat.com> > --- > arch/x86/platform/efi/efi.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) [...] > @@ -882,8 +886,10 @@ static void __init __efi_enter_virtual_mode(void) > > void __init efi_enter_virtual_mode(void) > { > - if (efi_enabled(EFI_PARAVIRT)) > + if (efi_enabled(EFI_PARAVIRT)) { > + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); > return; > + } The EFI_PARAVIRT folks purposely do not set this bit, so there should be no reason to clear it here.
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index eae91be..c42f49b 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -724,6 +724,7 @@ static void __init kexec_enter_virtual_mode(void) */ if (!efi_is_native()) { efi_unmap_memmap(); + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); return; } @@ -797,6 +798,7 @@ static void __init __efi_enter_virtual_mode(void) new_memmap = efi_map_regions(&count, &pg_shift); if (!new_memmap) { pr_err("Error reallocating memory, EFI runtime non-functional!\n"); + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); return; } @@ -804,8 +806,10 @@ static void __init __efi_enter_virtual_mode(void) BUG_ON(!efi.systab); - if (efi_setup_page_tables(__pa(new_memmap), 1 << pg_shift)) + if (efi_setup_page_tables(__pa(new_memmap), 1 << pg_shift)) { + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); return; + } efi_sync_low_kernel_mappings(); efi_dump_pagetable(); @@ -882,8 +886,10 @@ static void __init __efi_enter_virtual_mode(void) void __init efi_enter_virtual_mode(void) { - if (efi_enabled(EFI_PARAVIRT)) + if (efi_enabled(EFI_PARAVIRT)) { + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); return; + } if (efi_setup) kexec_enter_virtual_mode();
If enter virtual mode failed due to some reason other than the efi call the EFI_RUNTIME_SERVICES bit in efi.flags should be cleared thus users of efi runtime services can check the bit and handle the case instead of assume efi runtime is ok. Per Matt, if efi call SetVirtualAddressMap fails we will be not sure it's safe to make any assumptions about the state of the system. so kernel panics instead of clears EFI_RUNTIME_SERVICES bit. Signed-off-by: Dave Young <dyoung@redhat.com> --- arch/x86/platform/efi/efi.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)