svn commit: r348639 - stable/12/sys/riscv/riscv

[Mark Johnston]

Author: markj
Date: Tue Jun  4 17:25:45 2019
New Revision: 348639
URL: https://svnweb.freebsd.org/changeset/base/348639

Log:
  MFC r342765:
  Fix dirty bit handling in pmap_remove_write().

Modified:
  stable/12/sys/riscv/riscv/pmap.c
Directory Properties:
  stable/12/   (props changed)

Modified: stable/12/sys/riscv/riscv/pmap.c
==============================================================================
--- stable/12/sys/riscv/riscv/pmap.c	Tue Jun  4 17:25:22 2019	(r348638)
+++ stable/12/sys/riscv/riscv/pmap.c	Tue Jun  4 17:25:45 2019	(r348639)
@@ -2938,15 +2938,13 @@ retry_pv_loop:
 			}
 		}
 		l3 = pmap_l3(pmap, pv->pv_va);
-retry:
 		oldl3 = pmap_load(l3);
-
+retry:
 		if ((oldl3 & PTE_W) != 0) {
-			newl3 = oldl3 & ~PTE_W;
-			if (!atomic_cmpset_long(l3, oldl3, newl3))
+			newl3 = oldl3 & ~(PTE_D | PTE_W);
+			if (!atomic_fcmpset_long(l3, &oldl3, newl3))
 				goto retry;
-			/* TODO: check for PTE_D? */
-			if ((oldl3 & PTE_A) != 0)
+			if ((oldl3 & PTE_D) != 0)
 				vm_page_dirty(m);
 			pmap_invalidate_page(pmap, pv->pv_va);
 		}