svn commit: r294791 - head/sys/arm/arm

[Svatopluk Kraus]

Author: skra
Date: Tue Jan 26 10:24:18 2016
New Revision: 294791
URL: https://svnweb.freebsd.org/changeset/base/294791

Log:
  Don't do icache sync on kernel memory and keep in line with comment
  in elf_cpu_load_file(). The only time when the sync is needed is after
  kernel module is loaded and the relocation info is processed. And it's
  done in elf_cpu_load_file().

Modified:
  head/sys/arm/arm/pmap-v6-new.c

Modified: head/sys/arm/arm/pmap-v6-new.c
==============================================================================
--- head/sys/arm/arm/pmap-v6-new.c	Tue Jan 26 09:50:36 2016	(r294790)
+++ head/sys/arm/arm/pmap-v6-new.c	Tue Jan 26 10:24:18 2016	(r294791)
@@ -3799,14 +3799,19 @@ validate:
 		 * is set. Do it now, before the mapping is stored and made
 		 * valid for hardware table walk. If done later, there is a race
 		 * for other threads of current process in lazy loading case.
+		 * Don't do it for kernel memory which is mapped with exec
+		 * permission even if the memory isn't going to hold executable
+		 * code. The only time when icache sync is needed is after
+		 * kernel module is loaded and the relocation info is processed.
+		 * And it's done in elf_cpu_load_file().
 		 *
 		 * QQQ: (1) Does it exist any better way where
 		 *          or how to sync icache?
 		 *      (2) Now, we do it on a page basis.
 		 */
-		if ((prot & VM_PROT_EXECUTE) &&
-		    (m->md.pat_mode == PTE2_ATTR_WB_WA) &&
-		    ((opa != pa) || (opte2 & PTE2_NX)))
+		if ((prot & VM_PROT_EXECUTE) && pmap != kernel_pmap &&
+		    m->md.pat_mode == PTE2_ATTR_WB_WA &&
+		    (opa != pa || (opte2 & PTE2_NX)))
 			cache_icache_sync_fresh(va, pa, PAGE_SIZE);
 
 		npte2 |= PTE2_A;
@@ -4405,7 +4410,7 @@ pmap_enter_quick_locked(pmap_t pmap, vm_
 		l2prot |= PTE2_U | PTE2_NG;
 	if ((prot & VM_PROT_EXECUTE) == 0)
 		l2prot |= PTE2_NX;
-	else if (m->md.pat_mode == PTE2_ATTR_WB_WA) {
+	else if (m->md.pat_mode == PTE2_ATTR_WB_WA && pmap != kernel_pmap) {
 		/*
 		 * Sync icache if exec permission and attribute PTE2_ATTR_WB_WA
 		 * is set. QQQ: For more info, see comments in pmap_enter().
@@ -4476,7 +4481,7 @@ pmap_enter_pte1(pmap_t pmap, vm_offset_t
 		l1prot |= PTE1_U | PTE1_NG;
 	if ((prot & VM_PROT_EXECUTE) == 0)
 		l1prot |= PTE1_NX;
-	else if (m->md.pat_mode == PTE2_ATTR_WB_WA) {
+	else if (m->md.pat_mode == PTE2_ATTR_WB_WA && pmap != kernel_pmap) {
 		/*
 		 * Sync icache if exec permission and attribute PTE2_ATTR_WB_WA
 		 * is set. QQQ: For more info, see comments in pmap_enter().