Re: [PATCHv3 2/5] x86/boot/compressed/64: Print error if 5-level paging is not supported

Borislav Petkov
2017-12-04T19:31:18Z

On Mon, Dec 04, 2017 at 03:40:56PM +0300, Kirill A. Shutemov wrote:
> We cannot proceed booting if the machine doesn't support the paging mode
> kernel was compiled for.
>
> Getting error the usual way -- via validate_cpu() -- is not going to
> work. We need to enable appropriate paging mode before that, otherwise
> kernel would triple-fault during KASLR setup.
>
> This code will go away once we get support for boot-time switching
> between paging modes.
>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Cc: <stable@vger.kernel.org> [4.14+]
> ---
> arch/x86/boot/compressed/misc.c | 16 ++++++++++++++++
> arch/x86/boot/compressed/pgtable_64.c | 2 +-
> 2 files changed, 17 insertions(+), 1 deletion(-)

Reported-and-tested-by: Borislav Petkov <bp@suse.de>

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Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
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