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authorIngo Molnar <mingo@kernel.org>2017-11-06 09:49:28 +0100
committerIngo Molnar <mingo@kernel.org>2017-11-06 09:49:28 +0100
commit75ec4eb3dc84ee78533bd59bbb71992187bd86fd (patch)
treeb75afe1763e5a21bfe508301562c037fbae2b04d /arch/x86/mm
parent19c5787a5ff88a959e5854ab6ddef7f5777c5837 (diff)
parent15670bfe19905b1dcbb63137f40d718b59d84479 (diff)
downloadlinux-75ec4eb3dc84ee78533bd59bbb71992187bd86fd.tar.bz2
Merge branch 'x86/mm' into x86/asm, to pick up pending changes
Concentrate x86 MM and asm related changes into a single super-topic, in preparation for larger changes. Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/mm')
-rw-r--r--arch/x86/mm/init_64.c10
-rw-r--r--arch/x86/mm/kasan_init_64.c101
2 files changed, 85 insertions, 26 deletions
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 048fbe8fc274..adcea90a2046 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -1426,16 +1426,16 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
#if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HAVE_BOOTMEM_INFO_NODE)
void register_page_bootmem_memmap(unsigned long section_nr,
- struct page *start_page, unsigned long size)
+ struct page *start_page, unsigned long nr_pages)
{
unsigned long addr = (unsigned long)start_page;
- unsigned long end = (unsigned long)(start_page + size);
+ unsigned long end = (unsigned long)(start_page + nr_pages);
unsigned long next;
pgd_t *pgd;
p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
- unsigned int nr_pages;
+ unsigned int nr_pmd_pages;
struct page *page;
for (; addr < end; addr = next) {
@@ -1482,9 +1482,9 @@ void register_page_bootmem_memmap(unsigned long section_nr,
if (pmd_none(*pmd))
continue;
- nr_pages = 1 << (get_order(PMD_SIZE));
+ nr_pmd_pages = 1 << get_order(PMD_SIZE);
page = pmd_page(*pmd);
- while (nr_pages--)
+ while (nr_pmd_pages--)
get_page_bootmem(section_nr, page++,
SECTION_INFO);
}
diff --git a/arch/x86/mm/kasan_init_64.c b/arch/x86/mm/kasan_init_64.c
index bc84b73684b7..fe5760db7b19 100644
--- a/arch/x86/mm/kasan_init_64.c
+++ b/arch/x86/mm/kasan_init_64.c
@@ -15,6 +15,8 @@
extern struct range pfn_mapped[E820_MAX_ENTRIES];
+static p4d_t tmp_p4d_table[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE);
+
static int __init map_range(struct range *range)
{
unsigned long start;
@@ -30,8 +32,10 @@ static void __init clear_pgds(unsigned long start,
unsigned long end)
{
pgd_t *pgd;
+ /* See comment in kasan_init() */
+ unsigned long pgd_end = end & PGDIR_MASK;
- for (; start < end; start += PGDIR_SIZE) {
+ for (; start < pgd_end; start += PGDIR_SIZE) {
pgd = pgd_offset_k(start);
/*
* With folded p4d, pgd_clear() is nop, use p4d_clear()
@@ -42,29 +46,61 @@ static void __init clear_pgds(unsigned long start,
else
pgd_clear(pgd);
}
+
+ pgd = pgd_offset_k(start);
+ for (; start < end; start += P4D_SIZE)
+ p4d_clear(p4d_offset(pgd, start));
+}
+
+static inline p4d_t *early_p4d_offset(pgd_t *pgd, unsigned long addr)
+{
+ unsigned long p4d;
+
+ if (!IS_ENABLED(CONFIG_X86_5LEVEL))
+ return (p4d_t *)pgd;
+
+ p4d = __pa_nodebug(pgd_val(*pgd)) & PTE_PFN_MASK;
+ p4d += __START_KERNEL_map - phys_base;
+ return (p4d_t *)p4d + p4d_index(addr);
+}
+
+static void __init kasan_early_p4d_populate(pgd_t *pgd,
+ unsigned long addr,
+ unsigned long end)
+{
+ pgd_t pgd_entry;
+ p4d_t *p4d, p4d_entry;
+ unsigned long next;
+
+ if (pgd_none(*pgd)) {
+ pgd_entry = __pgd(_KERNPG_TABLE | __pa_nodebug(kasan_zero_p4d));
+ set_pgd(pgd, pgd_entry);
+ }
+
+ p4d = early_p4d_offset(pgd, addr);
+ do {
+ next = p4d_addr_end(addr, end);
+
+ if (!p4d_none(*p4d))
+ continue;
+
+ p4d_entry = __p4d(_KERNPG_TABLE | __pa_nodebug(kasan_zero_pud));
+ set_p4d(p4d, p4d_entry);
+ } while (p4d++, addr = next, addr != end && p4d_none(*p4d));
}
static void __init kasan_map_early_shadow(pgd_t *pgd)
{
- int i;
- unsigned long start = KASAN_SHADOW_START;
+ /* See comment in kasan_init() */
+ unsigned long addr = KASAN_SHADOW_START & PGDIR_MASK;
unsigned long end = KASAN_SHADOW_END;
+ unsigned long next;
- for (i = pgd_index(start); start < end; i++) {
- switch (CONFIG_PGTABLE_LEVELS) {
- case 4:
- pgd[i] = __pgd(__pa_nodebug(kasan_zero_pud) |
- _KERNPG_TABLE);
- break;
- case 5:
- pgd[i] = __pgd(__pa_nodebug(kasan_zero_p4d) |
- _KERNPG_TABLE);
- break;
- default:
- BUILD_BUG();
- }
- start += PGDIR_SIZE;
- }
+ pgd += pgd_index(addr);
+ do {
+ next = pgd_addr_end(addr, end);
+ kasan_early_p4d_populate(pgd, addr, next);
+ } while (pgd++, addr = next, addr != end);
}
#ifdef CONFIG_KASAN_INLINE
@@ -101,7 +137,7 @@ void __init kasan_early_init(void)
for (i = 0; i < PTRS_PER_PUD; i++)
kasan_zero_pud[i] = __pud(pud_val);
- for (i = 0; CONFIG_PGTABLE_LEVELS >= 5 && i < PTRS_PER_P4D; i++)
+ for (i = 0; IS_ENABLED(CONFIG_X86_5LEVEL) && i < PTRS_PER_P4D; i++)
kasan_zero_p4d[i] = __p4d(p4d_val);
kasan_map_early_shadow(early_top_pgt);
@@ -117,12 +153,35 @@ void __init kasan_init(void)
#endif
memcpy(early_top_pgt, init_top_pgt, sizeof(early_top_pgt));
+
+ /*
+ * We use the same shadow offset for 4- and 5-level paging to
+ * facilitate boot-time switching between paging modes.
+ * As result in 5-level paging mode KASAN_SHADOW_START and
+ * KASAN_SHADOW_END are not aligned to PGD boundary.
+ *
+ * KASAN_SHADOW_START doesn't share PGD with anything else.
+ * We claim whole PGD entry to make things easier.
+ *
+ * KASAN_SHADOW_END lands in the last PGD entry and it collides with
+ * bunch of things like kernel code, modules, EFI mapping, etc.
+ * We need to take extra steps to not overwrite them.
+ */
+ if (IS_ENABLED(CONFIG_X86_5LEVEL)) {
+ void *ptr;
+
+ ptr = (void *)pgd_page_vaddr(*pgd_offset_k(KASAN_SHADOW_END));
+ memcpy(tmp_p4d_table, (void *)ptr, sizeof(tmp_p4d_table));
+ set_pgd(&early_top_pgt[pgd_index(KASAN_SHADOW_END)],
+ __pgd(__pa(tmp_p4d_table) | _KERNPG_TABLE));
+ }
+
load_cr3(early_top_pgt);
__flush_tlb_all();
- clear_pgds(KASAN_SHADOW_START, KASAN_SHADOW_END);
+ clear_pgds(KASAN_SHADOW_START & PGDIR_MASK, KASAN_SHADOW_END);
- kasan_populate_zero_shadow((void *)KASAN_SHADOW_START,
+ kasan_populate_zero_shadow((void *)(KASAN_SHADOW_START & PGDIR_MASK),
kasan_mem_to_shadow((void *)PAGE_OFFSET));
for (i = 0; i < E820_MAX_ENTRIES; i++) {