# Re: \[PATCH 1/9\] x86, pkeys: add fault handling for PF\_PK page fault bit

- From: Mel Gorman \<hidden\>
- Date: 2016-07-07 14:40:40 
- List: linux-api
- Page: https://ratatoskr.run/linux-api/2016/07/4790195
- Thread: https://ratatoskr.run/linux-api/2016/07/4790123/t.md

```text
On Thu, Jul 07, 2016 at 05:47:20AM -0700, Dave Hansen wrote:
> 
> From: Dave Hansen <dave.hansen@linux.intel.com>
> 
> 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@linux.intel.com>

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

-- 
Mel Gorman
SUSE Labs

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