2021-12-04 17:42:05

by Arnd Bergmann

Subject: [PATCH] x86/efi: select ARCH_USE_MEMREMAP_PROT

From: Arnd Bergmann <[email protected]>

The patch to map the EFI memmap as encrypted introduces a
link failure in configurations without encryption support:

x86_64-linux-ld: arch/x86/platform/efi/quirks.o: in function `efi_arch_mem_reserve':
quirks.c:(.init.text+0x127): undefined reference to `early_memremap_prot'

Select the necessary symbol here as well to fix the build.

Fixes: 8f1dd76c9b55 ("x86/sme: Explicitly map new EFI memmap table as encrypted")
Signed-off-by: Arnd Bergmann <[email protected]>
---
arch/x86/Kconfig | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 05362527f6b5..93befe25d787 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1934,6 +1934,7 @@ config EFI
depends on ACPI
select UCS2_STRING
select EFI_RUNTIME_WRAPPERS
+ select ARCH_USE_MEMREMAP_PROT
help
This enables the kernel to use EFI runtime services that are
available (such as the EFI variable services).
--
2.29.2

2021-12-04 17:55:26

by Ard Biesheuvel

Subject: Re: [PATCH] x86/efi: select ARCH_USE_MEMREMAP_PROT

On Sat, 4 Dec 2021 at 18:42, Arnd Bergmann <[email protected]> wrote:
>
> From: Arnd Bergmann <[email protected]>
>
> The patch to map the EFI memmap as encrypted introduces a
> link failure in configurations without encryption support:
>
> x86_64-linux-ld: arch/x86/platform/efi/quirks.o: in function `efi_arch_mem_reserve':
> quirks.c:(.init.text+0x127): undefined reference to `early_memremap_prot'
>
> Select the necessary symbol here as well to fix the build.
>
> Fixes: 8f1dd76c9b55 ("x86/sme: Explicitly map new EFI memmap table as encrypted")
> Signed-off-by: Arnd Bergmann <[email protected]>

Thanks for the report. I'll fold this fix into the original patch instead.

> ---
> arch/x86/Kconfig | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 05362527f6b5..93befe25d787 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -1934,6 +1934,7 @@ config EFI
> depends on ACPI
> select UCS2_STRING
> select EFI_RUNTIME_WRAPPERS
> + select ARCH_USE_MEMREMAP_PROT
> help
> This enables the kernel to use EFI runtime services that are
> available (such as the EFI variable services).
> --
> 2.29.2
>

2021-12-05 15:15:35

by Tom Lendacky

Subject: Re: [PATCH] x86/efi: select ARCH_USE_MEMREMAP_PROT

On 12/4/21 11:55 AM, Ard Biesheuvel wrote:
> On Sat, 4 Dec 2021 at 18:42, Arnd Bergmann <[email protected]> wrote:
>>
>> From: Arnd Bergmann <[email protected]>
>>
>> The patch to map the EFI memmap as encrypted introduces a
>> link failure in configurations without encryption support:
>>
>> x86_64-linux-ld: arch/x86/platform/efi/quirks.o: in function `efi_arch_mem_reserve':
>> quirks.c:(.init.text+0x127): undefined reference to `early_memremap_prot'
>>
>> Select the necessary symbol here as well to fix the build.
>>
>> Fixes: 8f1dd76c9b55 ("x86/sme: Explicitly map new EFI memmap table as encrypted")
>> Signed-off-by: Arnd Bergmann <[email protected]>
>
> Thanks for the report. I'll fold this fix into the original patch instead.

Thanks Arnd and Ard!

Tom

>
>> ---
>> arch/x86/Kconfig | 1 +
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
>> index 05362527f6b5..93befe25d787 100644
>> --- a/arch/x86/Kconfig
>> +++ b/arch/x86/Kconfig
>> @@ -1934,6 +1934,7 @@ config EFI
>> depends on ACPI
>> select UCS2_STRING
>> select EFI_RUNTIME_WRAPPERS
>> + select ARCH_USE_MEMREMAP_PROT
>> help
>> This enables the kernel to use EFI runtime services that are
>> available (such as the EFI variable services).
>> --
>> 2.29.2
>>