Module Name: src
Committed By: maxv
Date: Sat Aug 1 06:35:00 UTC 2020
Modified Files:
src/sys/arch/aarch64/include: asan.h
Log Message:
Use large pages for the KASAN shadow, same as amd64, discussed with ryo@.
To generate a diff of this commit:
cvs rdiff -u -r1.8 -r1.9 src/sys/arch/aarch64/include/asan.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/aarch64/include/asan.h
diff -u src/sys/arch/aarch64/include/asan.h:1.8 src/sys/arch/aarch64/include/asan.h:1.9
--- src/sys/arch/aarch64/include/asan.h:1.8 Thu Jul 16 11:36:35 2020
+++ src/sys/arch/aarch64/include/asan.h Sat Aug 1 06:35:00 2020
@@ -1,7 +1,7 @@
-/* $NetBSD: asan.h,v 1.8 2020/07/16 11:36:35 skrll Exp $ */
+/* $NetBSD: asan.h,v 1.9 2020/08/01 06:35:00 maxv Exp $ */
/*
- * Copyright (c) 2018 The NetBSD Foundation, Inc.
+ * Copyright (c) 2018-2020 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
@@ -72,9 +72,28 @@ __md_palloc(void)
else
pa = pmap_alloc_pdp(pmap_kernel(), NULL, 0, false);
+ /* The page is zeroed. */
return pa;
}
+static inline paddr_t
+__md_palloc_large(void)
+{
+ struct pglist pglist;
+ int ret;
+
+ if (!uvm.page_init_done)
+ return 0;
+
+ ret = uvm_pglistalloc(L2_SIZE, 0, ~0UL, L2_SIZE, 0,
+ &pglist, 1, 0);
+ if (ret != 0)
+ return 0;
+
+ /* The page may not be zeroed. */
+ return VM_PAGE_TO_PHYS(TAILQ_FIRST(&pglist));
+}
+
static void
kasan_md_shadow_map_page(vaddr_t va)
{
@@ -121,8 +140,20 @@ kasan_md_shadow_map_page(vaddr_t va)
idx = l2pde_index(va);
pde = l2[idx];
if (!l2pde_valid(pde)) {
+ /* If possible, use L2_BLOCK to map it in advance. */
+ if ((pa = __md_palloc_large()) != 0) {
+ atomic_swap_64(&l2[idx], pa | L2_BLOCK |
+ LX_BLKPAG_UXN | LX_BLKPAG_PXN | LX_BLKPAG_AF |
+ LX_BLKPAG_SH_IS | LX_BLKPAG_AP_RW);
+ aarch64_tlbi_by_va(va);
+ __builtin_memset((void *)va, 0, L2_SIZE);
+ return;
+ }
pa = __md_palloc();
atomic_swap_64(&l2[idx], pa | L2_TABLE);
+ } else if (l2pde_is_block(pde)) {
+ /* This VA is already mapped as a block. */
+ return;
} else {
pa = l2pde_pa(pde);
}
