Commit f7bcd461 authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Dave Hansen
Browse files

x86/mm/pae: Use WRITE_ONCE() 



Disallow write-tearing, that would be really unfortunate.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20221022114425.038102604%40infradead.org
parent 7a9b8bdb

arch/x86/include/asm/pgtable-3level.h

+6 −6
Original line number Diff line number Diff line
@@ -27,9 +27,9 @@ 
 */

static inline void native_set_pte(pte_t *ptep, pte_t pte)

{

	ptep->pte_high = pte.pte_high;

	WRITE_ONCE(ptep->pte_high, pte.pte_high);

	smp_wmb();

	ptep->pte_low = pte.pte_low;

	WRITE_ONCE(ptep->pte_low, pte.pte_low);

}



static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
@@ -58,16 +58,16 @@ static inline void native_set_pud(pud_t *pudp, pud_t pud) 
static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr,

				    pte_t *ptep)

{

	ptep->pte_low = 0;

	WRITE_ONCE(ptep->pte_low, 0);

	smp_wmb();

	ptep->pte_high = 0;

	WRITE_ONCE(ptep->pte_high, 0);

}



static inline void native_pmd_clear(pmd_t *pmdp)

{

	pmdp->pmd_low = 0;

	WRITE_ONCE(pmdp->pmd_low, 0);

	smp_wmb();

	pmdp->pmd_high = 0;

	WRITE_ONCE(pmdp->pmd_high, 0);

}



static inline void native_pud_clear(pud_t *pudp)