[REVIEW][PATCH 15/20] signal/x86: Don't compute pkey in __do_page_fault

From: Eric W. Biederman
Date: Mon Sep 17 2018 - 20:13:23 EST


There are no more users of the computed pkey value in __do_page_fault
so stop computing the value.

Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
---
arch/x86/mm/fault.c | 4 ----
1 file changed, 4 deletions(-)

diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 7ba00519fa5d..f82106578364 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -1215,7 +1215,6 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code,
struct mm_struct *mm;
vm_fault_t fault, major = 0;
unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
- u32 pkey;

tsk = current;
mm = tsk->mm;
@@ -1387,10 +1386,7 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code,
* (potentially after handling any pending signal during the return to
* userland). The return to userland is identified whenever
* FAULT_FLAG_USER|FAULT_FLAG_KILLABLE are both set in flags.
- * Thus we have to be careful about not touching vma after handling the
- * fault, so we read the pkey beforehand.
*/
- pkey = vma_pkey(vma);
fault = handle_mm_fault(vma, address, flags);
major |= fault & VM_FAULT_MAJOR;

--
2.17.1