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Date:      Thu, 3 Jan 2019 16:19:33 +0000 (UTC)
From:      Mark Johnston <markj@FreeBSD.org>
To:        src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org
Subject:   svn commit: r342733 - head/sys/riscv/riscv
Message-ID:  <201901031619.x03GJXB4038151@repo.freebsd.org>
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Author: markj
Date: Thu Jan  3 16:19:32 2019
New Revision: 342733
URL: https://svnweb.freebsd.org/changeset/base/342733

Log:
  Set PTE_U on PTEs created by pmap_enter_quick().
  
  Otherwise prefaulted entries are not accessible from user mode and
  end up triggering a fault upon access, so prefaulting has no effect.
  
  Reviewed by:	jhb, kib
  MFC after:	1 week
  Sponsored by:	The FreeBSD Foundation
  Differential Revision:	https://reviews.freebsd.org/D18718

Modified:
  head/sys/riscv/riscv/pmap.c

Modified: head/sys/riscv/riscv/pmap.c
==============================================================================
--- head/sys/riscv/riscv/pmap.c	Thu Jan  3 16:15:28 2019	(r342732)
+++ head/sys/riscv/riscv/pmap.c	Thu Jan  3 16:19:32 2019	(r342733)
@@ -2365,19 +2365,14 @@ pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va, v
 	 */
 	pmap_resident_count_inc(pmap, 1);
 
-	pa = VM_PAGE_TO_PHYS(m);
-	pn = (pa / PAGE_SIZE);
-
-	entry = PTE_V | PTE_R;
-	if (prot & VM_PROT_EXECUTE)
-		entry |= PTE_X;
-	entry |= (pn << PTE_PPN0_S);
-
-	/*
-	 * Now validate mapping with RO protection
-	 */
+	newl3 = ((VM_PAGE_TO_PHYS(m) / PAGE_SIZE) << PTE_PPN0_S) |
+	    PTE_V | PTE_R;
+	if ((prot & VM_PROT_EXECUTE) != 0)
+		newl3 |= PTE_X;
 	if ((m->oflags & VPO_UNMANAGED) == 0)
-		entry |= PTE_SW_MANAGED;
+		newl3 |= PTE_SW_MANAGED;
+	if (va < VM_MAX_USER_ADDRESS)
+		newl3 |= PTE_U;
 
 	/*
 	 * Sync the i-cache on all harts before updating the PTE
@@ -2386,7 +2381,7 @@ pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va, v
 	if (prot & VM_PROT_EXECUTE)
 		pmap_sync_icache(pmap, va, PAGE_SIZE);
 
-	pmap_store(l3, entry);
+	pmap_store(l3, newl3);
 
 	pmap_invalidate_page(pmap, va);
 	return (mpte);

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