Re: [PATCH 1/9] x86, pkeys: add fault handling for PF_PK page fault bit

From: Mel Gorman
Date: Thu Jul 07 2016 - 10:40:48 EST


On Thu, Jul 07, 2016 at 05:47:20AM -0700, Dave Hansen wrote:
>
> From: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
>
> PF_PK means that a memory access violated the protection key
> access restrictions. It is unconditionally an access_error()
> because the permissions set on the VMA don't matter (the PKRU
> value overrides it), and we never "resolve" PK faults (like
> how a COW can "resolve write fault).
>
> Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>

An access fault gets propgated as SEGV_PKUERR. What happens if glibc
does not recognise it?

--
Mel Gorman
SUSE Labs