Re: [PATCHv2 0/2] efi: Fix alignenment issues in unaccepted memory code

[Tom Lendacky]

On 2/17/26 04:49, Kiryl Shutsemau (Meta) wrote:
> This series addresses two issues related to unaligned physical addresses
> and sizes when handling EFI unaccepted memory. These issues were
> identified as potential sources of kernel panics in Intel TDX
> environments due to incomplete memory reservation or missing "guard page"
> extensions.
> 
> The first patch fixes the reservation of the unaccepted memory table
> itself in efi_config_parse_tables(). It ensures the entire page range
> covering the table is reserved even if the table doesn't start on a
> page boundary.
> 
> The second patch ensures that memory acceptance requests in
> accept_memory() and range_contains_unaccepted_memory() are page-aligned
> before performing the unit_size alignment check. This prevents skipping
> the necessary "guard page" extension for unaligned ranges, which is
> required to avoid crashes with load_unaligned_zeropad().
> 
> v2:
>  - Fix 'end' calculation in the second patch (Tom)
> 
> Kiryl Shutsemau (Meta) (2):
>   efi: Fix reservation of unaccepted memory table
>   efi: Align unaccepted memory range to page boundary
> 
>  drivers/firmware/efi/efi.c               |  8 ++++----
>  drivers/firmware/efi/unaccepted_memory.c | 10 ++++++++--
>  2 files changed, 12 insertions(+), 6 deletions(-)

Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx>

>