On Thu, 2016-12-01 at 09:26 -0800, Andy Lutomirski wrote:
> This is a backport of:
> commit fc0e81b2bea0ebceb71889b61d2240856141c9ee upstream
>
> On the 80486 DX, it seems that some exceptions may leave garbage in
> the high bits of CS. This causes sporadic failures in which
> early_fixup_exception() refuses to fix up an exception.
>
> As far as I can tell, this has been buggy for a long time, but the
> problem seems to have been exacerbated by commits:
>
> 1e02ce4cccdc ("x86: Store a per-cpu shadow copy of CR4")
> e1bfc11c5a6f ("x86/init: Fix cr4_init_shadow() on CR4-less machines")
>
> This appears to have broken for as long as we've had early
> exception handling.
>
> [ This backport should apply to kernels from 3.4 - 4.5. ]
[...]
Queued up for 3.16, thanks.
Ben.
--
Ben Hutchings
Lowery's Law:
If it jams, force it. If it breaks, it needed replacing
anyway.
Attachment:
signature.asc
Description: This is a digitally signed message part