leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

x86/pkeys: Add fault handling for PF_PK page fault bit

Browse Source 
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>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: linux-arch@vger.kernel.org
Cc: Dave Hansen <dave@sr71.net>
Cc: arnd@arndb.de
Cc: linux-api@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: luto@kernel.org
Cc: akpm@linux-foundation.org
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/20160729163010.DD1FE1ED@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Dave Hansen 2016-07-29 09:30:10 -07:00 committed by Thomas Gleixner
parent c6935931c1
commit e8c6226d48
1 changed files with 9 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
arch/x86/mm/fault.c
View File

@ -1112,6 +1112,15 @@ access_error(unsigned long error_code, struct vm_area_struct *vma)
{
/* This is only called for the current mm, so: */
bool foreign = false;
/*
* Read or write was blocked by protection keys. This is
* always an unconditional error and can never result in
* a follow-up action to resolve the fault, like a COW.
*/
if (error_code & PF_PK)
return 1;
/*
* Make sure to check the VMA so that we do not perform
* faults just to hit a PF_PK as soon as we fill in a