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| author | Tony Lindgren <tony@atomide.com> | 2017-03-06 08:37:53 -0800 |
|---|---|---|
| committer | Tony Lindgren <tony@atomide.com> | 2017-03-06 08:37:53 -0800 |
| commit | e24bce8fb4c26bd0d8eca74cbbee1ad049246be3 (patch) | |
| tree | c219c2ec183633aa15841fca5b055a09d2d0b980 /arch/x86/mm/dump_pagetables.c | |
| parent | b92675d998a9fa37fe9e0e35053a95b4a23c158b (diff) | |
| parent | c1ae3cfa0e89fa1a7ecc4c99031f5e9ae99d9201 (diff) | |
| download | linux-e24bce8fb4c26bd0d8eca74cbbee1ad049246be3.tar.gz | |
Merge tag 'v4.11-rc1' into omap-for-v4.11/fixes
Linux 4.11-rc1
Diffstat (limited to 'arch/x86/mm/dump_pagetables.c')
| -rw-r--r-- | arch/x86/mm/dump_pagetables.c | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c index 8aa6bea1cd6c..58b5bee7ea27 100644 --- a/arch/x86/mm/dump_pagetables.c +++ b/arch/x86/mm/dump_pagetables.c @@ -18,6 +18,7 @@ #include <linux/sched.h> #include <linux/seq_file.h> +#include <asm/kasan.h> #include <asm/pgtable.h> /* @@ -51,6 +52,10 @@ enum address_markers_idx { LOW_KERNEL_NR, VMALLOC_START_NR, VMEMMAP_START_NR, +#ifdef CONFIG_KASAN + KASAN_SHADOW_START_NR, + KASAN_SHADOW_END_NR, +#endif # ifdef CONFIG_X86_ESPFIX64 ESPFIX_START_NR, # endif @@ -76,6 +81,10 @@ static struct addr_marker address_markers[] = { { 0/* PAGE_OFFSET */, "Low Kernel Mapping" }, { 0/* VMALLOC_START */, "vmalloc() Area" }, { 0/* VMEMMAP_START */, "Vmemmap" }, +#ifdef CONFIG_KASAN + { KASAN_SHADOW_START, "KASAN shadow" }, + { KASAN_SHADOW_END, "KASAN shadow end" }, +#endif # ifdef CONFIG_X86_ESPFIX64 { ESPFIX_BASE_ADDR, "ESPfix Area", 16 }, # endif @@ -327,18 +336,31 @@ static void walk_pmd_level(struct seq_file *m, struct pg_state *st, pud_t addr, #if PTRS_PER_PUD > 1 +/* + * This is an optimization for CONFIG_DEBUG_WX=y + CONFIG_KASAN=y + * KASAN fills page tables with the same values. Since there is no + * point in checking page table more than once we just skip repeated + * entries. This saves us dozens of seconds during boot. + */ +static bool pud_already_checked(pud_t *prev_pud, pud_t *pud, bool checkwx) +{ + return checkwx && prev_pud && (pud_val(*prev_pud) == pud_val(*pud)); +} + static void walk_pud_level(struct seq_file *m, struct pg_state *st, pgd_t addr, unsigned long P) { int i; pud_t *start; pgprotval_t prot; + pud_t *prev_pud = NULL; start = (pud_t *) pgd_page_vaddr(addr); for (i = 0; i < PTRS_PER_PUD; i++) { st->current_address = normalize_addr(P + i * PUD_LEVEL_MULT); - if (!pud_none(*start)) { + if (!pud_none(*start) && + !pud_already_checked(prev_pud, start, st->check_wx)) { if (pud_large(*start) || !pud_present(*start)) { prot = pud_flags(*start); note_page(m, st, __pgprot(prot), 2); @@ -349,6 +371,7 @@ static void walk_pud_level(struct seq_file *m, struct pg_state *st, pgd_t addr, } else note_page(m, st, __pgprot(0), 2); + prev_pud = start; start++; } } |