path: root/arch/powerpc/mm/pgtable-radix.c
diff options
authorAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>2019-03-05 15:46:33 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-03-05 21:07:18 -0800
commit5b323367ef2567dff0d3daff477186002754f0bd (patch)
tree48198967c06de704b46750342fdce8ec4677461d /arch/powerpc/mm/pgtable-radix.c
parentmm: update ptep_modify_prot_commit to take old pte value as arg (diff)
arch/powerpc/mm: Nest MMU workaround for mprotect RW upgrade
NestMMU requires us to mark the pte invalid and flush the tlb when we do a RW upgrade of pte. We fixed a variant of this in the fault path in bd5050e38aec ("powerpc/mm/radix: Change pte relax sequence to handle nest MMU hang"). Do the same for mprotect upgrades. Hugetlb is handled in the next patch. Link: http://lkml.kernel.org/r/20190116085035.29729-4-aneesh.kumar@linux.ibm.com Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
1 files changed, 18 insertions, 0 deletions
diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c
index 931156069a81..dced3cd241c2 100644
--- a/arch/powerpc/mm/pgtable-radix.c
+++ b/arch/powerpc/mm/pgtable-radix.c
@@ -1063,3 +1063,21 @@ void radix__ptep_set_access_flags(struct vm_area_struct *vma, pte_t *ptep,
/* See ptesync comment in radix__set_pte_at */
+void radix__ptep_modify_prot_commit(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep,
+ pte_t old_pte, pte_t pte)
+ struct mm_struct *mm = vma->vm_mm;
+ /*
+ * To avoid NMMU hang while relaxing access we need to flush the tlb before
+ * we set the new value. We need to do this only for radix, because hash
+ * translation does flush when updating the linux pte.
+ */
+ if (is_pte_rw_upgrade(pte_val(old_pte), pte_val(pte)) &&
+ (atomic_read(&mm->context.copros) > 0))
+ radix__flush_tlb_page(vma, addr);
+ set_pte_at(mm, addr, ptep, pte);