Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64

Pull arm64 fixes from Catalin Marinas:
 - Page protection fixes, including proper PAGE_NONE handling
 - Timezone vdso sequence counting fix
 - Additional compat syscall wiring

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
  arm64: compat: add syscall table entries for new syscalls
  arm64: mm: introduce present, faulting entries for PAGE_NONE
  arm64: mm: only wrprotect clean ptes if they are present
  arm64: vdso: remove broken, redundant sequence counting for timezones

4 files changed, 26 insertions, 23 deletions

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 64b133949502..e333a243bfcc 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -24,7 +24,8 @@
 /*
  * Software defined PTE bits definition.
  */
-#define PTE_VALID               (_AT(pteval_t, 1) << 0) /* pte_present() check */
+#define PTE_VALID               (_AT(pteval_t, 1) << 0)
+#define PTE_PROT_NONE           (_AT(pteval_t, 1) << 1) /* only when !PTE_VALID */
 #define PTE_FILE                (_AT(pteval_t, 1) << 2) /* only when !pte_present() */
 #define PTE_DIRTY               (_AT(pteval_t, 1) << 55)
 #define PTE_SPECIAL             (_AT(pteval_t, 1) << 56)
@@ -60,9 +61,12 @@ extern void __pgd_error(const char *file, int line, unsigned long val);
 
 extern pgprot_t pgprot_default;
 
-#define _MOD_PROT(p, b) __pgprot(pgprot_val(p) | (b))
+#define __pgprot_modify(prot,mask,bits) \
+        __pgprot((pgprot_val(prot) & ~(mask)) | (bits))
+
+#define _MOD_PROT(p, b)         __pgprot_modify(p, 0, b)
 
-#define PAGE_NONE               _MOD_PROT(pgprot_default, PTE_NG | PTE_PXN | PTE_UXN | PTE_RDONLY)
+#define PAGE_NONE               __pgprot_modify(pgprot_default, PTE_TYPE_MASK, PTE_PROT_NONE)
 #define PAGE_SHARED             _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_PXN | PTE_UXN)
 #define PAGE_SHARED_EXEC        _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_PXN)
 #define PAGE_COPY               _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_PXN | PTE_UXN | PTE_RDONLY)
@@ -72,7 +76,7 @@ extern pgprot_t pgprot_default;
 #define PAGE_KERNEL             _MOD_PROT(pgprot_default, PTE_PXN | PTE_UXN | PTE_DIRTY)
 #define PAGE_KERNEL_EXEC        _MOD_PROT(pgprot_default, PTE_UXN | PTE_DIRTY)
 
-#define __PAGE_NONE             __pgprot(_PAGE_DEFAULT | PTE_NG | PTE_PXN | PTE_UXN | PTE_RDONLY)
+#define __PAGE_NONE             __pgprot(((_PAGE_DEFAULT) & ~PTE_TYPE_MASK) | PTE_PROT_NONE)
 #define __PAGE_SHARED           __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN)
 #define __PAGE_SHARED_EXEC      __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN)
 #define __PAGE_COPY             __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN | PTE_RDONLY)
@@ -125,16 +129,15 @@ extern struct page *empty_zero_page;
 /*
  * The following only work if pte_present(). Undefined behaviour otherwise.
  */
-#define pte_present(pte)        (pte_val(pte) & PTE_VALID)
+#define pte_present(pte)        (pte_val(pte) & (PTE_VALID | PTE_PROT_NONE))
 #define pte_dirty(pte)          (pte_val(pte) & PTE_DIRTY)
 #define pte_young(pte)          (pte_val(pte) & PTE_AF)
 #define pte_special(pte)        (pte_val(pte) & PTE_SPECIAL)
 #define pte_write(pte)          (!(pte_val(pte) & PTE_RDONLY))
 #define pte_exec(pte)           (!(pte_val(pte) & PTE_UXN))
 
-#define pte_present_exec_user(pte) \
-        ((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == \
-         (PTE_VALID | PTE_USER))
+#define pte_valid_user(pte) \
+        ((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER))
 
 #define PTE_BIT_FUNC(fn,op) \
 static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
@@ -157,10 +160,13 @@ extern void __sync_icache_dcache(pte_t pteval, unsigned long addr);
 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
                               pte_t *ptep, pte_t pte)
 {
-        if (pte_present_exec_user(pte))
-                __sync_icache_dcache(pte, addr);
-        if (!pte_dirty(pte))
-                pte = pte_wrprotect(pte);
+        if (pte_valid_user(pte)) {
+                if (pte_exec(pte))
+                        __sync_icache_dcache(pte, addr);
+                if (!pte_dirty(pte))
+                        pte = pte_wrprotect(pte);
+        }
+
         set_pte(ptep, pte);
 }
 
@@ -170,9 +176,6 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
 #define pte_huge(pte)           ((pte_val(pte) & PTE_TYPE_MASK) == PTE_TYPE_HUGEPAGE)
 #define pte_mkhuge(pte)         (__pte((pte_val(pte) & ~PTE_TYPE_MASK) | PTE_TYPE_HUGEPAGE))
 
-#define __pgprot_modify(prot,mask,bits)         \
-        __pgprot((pgprot_val(prot) & ~(mask)) | (bits))
-
 #define __HAVE_ARCH_PTE_SPECIAL
 
 /*
@@ -264,7 +267,8 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
 
 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 {
-        const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY;
+        const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
+                              PTE_PROT_NONE | PTE_VALID;
         pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
         return pte;
 }
diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h
index 58432625fdb3..5ef47ba3ed45 100644
--- a/arch/arm64/include/asm/unistd32.h
+++ b/arch/arm64/include/asm/unistd32.h
@@ -395,8 +395,13 @@ __SYSCALL(370, sys_name_to_handle_at)
 __SYSCALL(371, compat_sys_open_by_handle_at)
 __SYSCALL(372, compat_sys_clock_adjtime)
 __SYSCALL(373, sys_syncfs)
+__SYSCALL(374, compat_sys_sendmmsg)
+__SYSCALL(375, sys_setns)
+__SYSCALL(376, compat_sys_process_vm_readv)
+__SYSCALL(377, compat_sys_process_vm_writev)
+__SYSCALL(378, sys_ni_syscall)                  /* 378 for kcmp */
 
-#define __NR_compat_syscalls            374
+#define __NR_compat_syscalls            379
 
 /*
  * Compat syscall numbers used by the AArch64 kernel.
diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
index c958cb84d75f..6a389dc1bd49 100644
--- a/arch/arm64/kernel/vdso.c
+++ b/arch/arm64/kernel/vdso.c
@@ -252,10 +252,6 @@ void update_vsyscall(struct timekeeper *tk)
 
 void update_vsyscall_tz(void)
 {
-        ++vdso_data->tb_seq_count;
-        smp_wmb();
         vdso_data->tz_minuteswest       = sys_tz.tz_minuteswest;
         vdso_data->tz_dsttime           = sys_tz.tz_dsttime;
-        smp_wmb();
-        ++vdso_data->tb_seq_count;
 }
diff --git a/arch/arm64/kernel/vdso/gettimeofday.S b/arch/arm64/kernel/vdso/gettimeofday.S
index 8bf658d974f9..f0a6d10b5211 100644
--- a/arch/arm64/kernel/vdso/gettimeofday.S
+++ b/arch/arm64/kernel/vdso/gettimeofday.S
@@ -73,8 +73,6 @@ ENTRY(__kernel_gettimeofday)
         /* If tz is NULL, return 0. */
         cbz     x1, 3f
         ldp     w4, w5, [vdso_data, #VDSO_TZ_MINWEST]
-        seqcnt_read w9
-        seqcnt_check w9, 1b
         stp     w4, w5, [x1, #TZ_MINWEST]
 3:
         mov     x0, xzr