Merge 4.4.110 into android-4.4

Changes in 4.4.110
	x86/boot: Add early cmdline parsing for options with arguments
	KAISER: Kernel Address Isolation
	kaiser: merged update
	kaiser: do not set _PAGE_NX on pgd_none
	kaiser: stack map PAGE_SIZE at THREAD_SIZE-PAGE_SIZE
	kaiser: fix build and FIXME in alloc_ldt_struct()
	kaiser: KAISER depends on SMP
	kaiser: fix regs to do_nmi() ifndef CONFIG_KAISER
	kaiser: fix perf crashes
	kaiser: ENOMEM if kaiser_pagetable_walk() NULL
	kaiser: tidied up asm/kaiser.h somewhat
	kaiser: tidied up kaiser_add/remove_mapping slightly
	kaiser: kaiser_remove_mapping() move along the pgd
	kaiser: cleanups while trying for gold link
	kaiser: name that 0x1000 KAISER_SHADOW_PGD_OFFSET
	kaiser: delete KAISER_REAL_SWITCH option
	kaiser: vmstat show NR_KAISERTABLE as nr_overhead
	kaiser: enhanced by kernel and user PCIDs
	kaiser: load_new_mm_cr3() let SWITCH_USER_CR3 flush user
	kaiser: PCID 0 for kernel and 128 for user
	kaiser: x86_cr3_pcid_noflush and x86_cr3_pcid_user
	kaiser: paranoid_entry pass cr3 need to paranoid_exit
	kaiser: _pgd_alloc() without __GFP_REPEAT to avoid stalls
	kaiser: fix unlikely error in alloc_ldt_struct()
	kaiser: add "nokaiser" boot option, using ALTERNATIVE
	x86/kaiser: Rename and simplify X86_FEATURE_KAISER handling
	x86/kaiser: Check boottime cmdline params
	kaiser: use ALTERNATIVE instead of x86_cr3_pcid_noflush
	kaiser: drop is_atomic arg to kaiser_pagetable_walk()
	kaiser: asm/tlbflush.h handle noPGE at lower level
	kaiser: kaiser_flush_tlb_on_return_to_user() check PCID
	x86/paravirt: Dont patch flush_tlb_single
	x86/kaiser: Reenable PARAVIRT
	kaiser: disabled on Xen PV
	x86/kaiser: Move feature detection up
	KPTI: Rename to PAGE_TABLE_ISOLATION
	KPTI: Report when enabled
	x86, vdso, pvclock: Simplify and speed up the vdso pvclock reader
	x86/vdso: Get pvclock data from the vvar VMA instead of the fixmap
	x86/kasan: Clear kasan_zero_page after TLB flush
	kaiser: Set _PAGE_NX only if supported
	Linux 4.4.110

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

1 files changed, 47 insertions, 16 deletions

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 4540e8880cd9..ac9c7797b632 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -52,6 +52,7 @@ static DEFINE_SPINLOCK(cpa_lock);
 #define CPA_FLUSHTLB 1
 #define CPA_ARRAY 2
 #define CPA_PAGES_ARRAY 4
+#define CPA_FREE_PAGETABLES 8
 
 #ifdef CONFIG_PROC_FS
 static unsigned long direct_pages_count[PG_LEVEL_NUM];
@@ -723,10 +724,13 @@ static int split_large_page(struct cpa_data *cpa, pte_t *kpte,
 	return 0;
 }
 
-static bool try_to_free_pte_page(pte_t *pte)
+static bool try_to_free_pte_page(struct cpa_data *cpa, pte_t *pte)
 {
 	int i;
 
+	if (!(cpa->flags & CPA_FREE_PAGETABLES))
+		return false;
+
 	for (i = 0; i < PTRS_PER_PTE; i++)
 		if (!pte_none(pte[i]))
 			return false;
@@ -735,10 +739,13 @@ static bool try_to_free_pte_page(pte_t *pte)
 	return true;
 }
 
-static bool try_to_free_pmd_page(pmd_t *pmd)
+static bool try_to_free_pmd_page(struct cpa_data *cpa, pmd_t *pmd)
 {
 	int i;
 
+	if (!(cpa->flags & CPA_FREE_PAGETABLES))
+		return false;
+
 	for (i = 0; i < PTRS_PER_PMD; i++)
 		if (!pmd_none(pmd[i]))
 			return false;
@@ -759,7 +766,9 @@ static bool try_to_free_pud_page(pud_t *pud)
 	return true;
 }
 
-static bool unmap_pte_range(pmd_t *pmd, unsigned long start, unsigned long end)
+static bool unmap_pte_range(struct cpa_data *cpa, pmd_t *pmd,
+			    unsigned long start,
+			    unsigned long end)
 {
 	pte_t *pte = pte_offset_kernel(pmd, start);
 
@@ -770,22 +779,23 @@ static bool unmap_pte_range(pmd_t *pmd, unsigned long start, unsigned long end)
 		pte++;
 	}
 
-	if (try_to_free_pte_page((pte_t *)pmd_page_vaddr(*pmd))) {
+	if (try_to_free_pte_page(cpa, (pte_t *)pmd_page_vaddr(*pmd))) {
 		pmd_clear(pmd);
 		return true;
 	}
 	return false;
 }
 
-static void __unmap_pmd_range(pud_t *pud, pmd_t *pmd,
+static void __unmap_pmd_range(struct cpa_data *cpa, pud_t *pud, pmd_t *pmd,
 			      unsigned long start, unsigned long end)
 {
-	if (unmap_pte_range(pmd, start, end))
-		if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud)))
+	if (unmap_pte_range(cpa, pmd, start, end))
+		if (try_to_free_pmd_page(cpa, (pmd_t *)pud_page_vaddr(*pud)))
 			pud_clear(pud);
 }
 
-static void unmap_pmd_range(pud_t *pud, unsigned long start, unsigned long end)
+static void unmap_pmd_range(struct cpa_data *cpa, pud_t *pud,
+			    unsigned long start, unsigned long end)
 {
 	pmd_t *pmd = pmd_offset(pud, start);
 
@@ -796,7 +806,7 @@ static void unmap_pmd_range(pud_t *pud, unsigned long start, unsigned long end)
 		unsigned long next_page = (start + PMD_SIZE) & PMD_MASK;
 		unsigned long pre_end = min_t(unsigned long, end, next_page);
 
-		__unmap_pmd_range(pud, pmd, start, pre_end);
+		__unmap_pmd_range(cpa, pud, pmd, start, pre_end);
 
 		start = pre_end;
 		pmd++;
@@ -809,7 +819,8 @@ static void unmap_pmd_range(pud_t *pud, unsigned long start, unsigned long end)
 		if (pmd_large(*pmd))
 			pmd_clear(pmd);
 		else
-			__unmap_pmd_range(pud, pmd, start, start + PMD_SIZE);
+			__unmap_pmd_range(cpa, pud, pmd,
+					  start, start + PMD_SIZE);
 
 		start += PMD_SIZE;
 		pmd++;
@@ -819,17 +830,19 @@ static void unmap_pmd_range(pud_t *pud, unsigned long start, unsigned long end)
 	 * 4K leftovers?
 	 */
 	if (start < end)
-		return __unmap_pmd_range(pud, pmd, start, end);
+		return __unmap_pmd_range(cpa, pud, pmd, start, end);
 
 	/*
 	 * Try again to free the PMD page if haven't succeeded above.
 	 */
 	if (!pud_none(*pud))
-		if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud)))
+		if (try_to_free_pmd_page(cpa, (pmd_t *)pud_page_vaddr(*pud)))
 			pud_clear(pud);
 }
 
-static void unmap_pud_range(pgd_t *pgd, unsigned long start, unsigned long end)
+static void __unmap_pud_range(struct cpa_data *cpa, pgd_t *pgd,
+			      unsigned long start,
+			      unsigned long end)
 {
 	pud_t *pud = pud_offset(pgd, start);
 
@@ -840,7 +853,7 @@ static void unmap_pud_range(pgd_t *pgd, unsigned long start, unsigned long end)
 		unsigned long next_page = (start + PUD_SIZE) & PUD_MASK;
 		unsigned long pre_end	= min_t(unsigned long, end, next_page);
 
-		unmap_pmd_range(pud, start, pre_end);
+		unmap_pmd_range(cpa, pud, start, pre_end);
 
 		start = pre_end;
 		pud++;
@@ -854,7 +867,7 @@ static void unmap_pud_range(pgd_t *pgd, unsigned long start, unsigned long end)
 		if (pud_large(*pud))
 			pud_clear(pud);
 		else
-			unmap_pmd_range(pud, start, start + PUD_SIZE);
+			unmap_pmd_range(cpa, pud, start, start + PUD_SIZE);
 
 		start += PUD_SIZE;
 		pud++;
@@ -864,7 +877,7 @@ static void unmap_pud_range(pgd_t *pgd, unsigned long start, unsigned long end)
 	 * 2M leftovers?
 	 */
 	if (start < end)
-		unmap_pmd_range(pud, start, end);
+		unmap_pmd_range(cpa, pud, start, end);
 
 	/*
 	 * No need to try to free the PUD page because we'll free it in
@@ -872,6 +885,24 @@ static void unmap_pud_range(pgd_t *pgd, unsigned long start, unsigned long end)
 	 */
 }
 
+static void unmap_pud_range(pgd_t *pgd, unsigned long start, unsigned long end)
+{
+	struct cpa_data cpa = {
+		.flags = CPA_FREE_PAGETABLES,
+	};
+
+	__unmap_pud_range(&cpa, pgd, start, end);
+}
+
+void unmap_pud_range_nofree(pgd_t *pgd, unsigned long start, unsigned long end)
+{
+	struct cpa_data cpa = {
+		.flags = 0,
+	};
+
+	__unmap_pud_range(&cpa, pgd, start, end);
+}
+
 static void unmap_pgd_range(pgd_t *root, unsigned long addr, unsigned long end)
 {
 	pgd_t *pgd_entry = root + pgd_index(addr);