Merge branch 'topic/pkey' into next

This is a branch with a mixture of mm, x86 and powerpc commits all relating to some minor cross-arch pkeys consolidation. The x86/mm changes have been reviewed by Ingo & Dave Hansen and the tree has been in linux-next for some weeks without issue.
mariux64 · Jun 3, 2018 · 2135a6e · 2135a6e
2 parents f1079d3 + d86a4ba
commit 2135a6e
Showing 8 changed files with 41 additions and 53 deletions.
diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
@@ -250,11 +250,6 @@ static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
 #define thread_pkey_regs_restore(new_thread, old_thread)
 #define thread_pkey_regs_init(thread)
 
-static inline int vma_pkey(struct vm_area_struct *vma)
-{
-	return 0;
-}
-
 static inline u64 pte_to_hpte_pkey_bits(u64 pteflags)
 {
 	return 0x0UL;

diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
@@ -15,19 +15,6 @@ DECLARE_STATIC_KEY_TRUE(pkey_disabled);
 extern int pkeys_total; /* total pkeys as per device tree */
 extern u32 initial_allocation_mask; /* bits set for reserved keys */
 
-/*
- * Define these here temporarily so we're not dependent on patching linux/mm.h.
- * Once it's updated we can drop these.
- */
-#ifndef VM_PKEY_BIT0
-# define VM_PKEY_SHIFT	VM_HIGH_ARCH_BIT_0
-# define VM_PKEY_BIT0	VM_HIGH_ARCH_0
-# define VM_PKEY_BIT1	VM_HIGH_ARCH_1
-# define VM_PKEY_BIT2	VM_HIGH_ARCH_2
-# define VM_PKEY_BIT3	VM_HIGH_ARCH_3
-# define VM_PKEY_BIT4	VM_HIGH_ARCH_4
-#endif
-
 #define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | VM_PKEY_BIT1 | VM_PKEY_BIT2 | \
 			    VM_PKEY_BIT3 | VM_PKEY_BIT4)
 

diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
@@ -288,21 +288,6 @@ static inline void arch_unmap(struct mm_struct *mm, struct vm_area_struct *vma,
 		mpx_notify_unmap(mm, vma, start, end);
 }
 
-#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
-static inline int vma_pkey(struct vm_area_struct *vma)
-{
-	unsigned long vma_pkey_mask = VM_PKEY_BIT0 | VM_PKEY_BIT1 |
-				      VM_PKEY_BIT2 | VM_PKEY_BIT3;
-
-	return (vma->vm_flags & vma_pkey_mask) >> VM_PKEY_SHIFT;
-}
-#else
-static inline int vma_pkey(struct vm_area_struct *vma)
-{
-	return 0;
-}
-#endif
-
 /*
  * We only want to enforce protection keys on the current process
  * because we effectively have no access to PKRU for other

diff --git a/arch/x86/include/asm/pkeys.h b/arch/x86/include/asm/pkeys.h
@@ -7,6 +7,11 @@
 extern int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
 		unsigned long init_val);
 
+static inline bool arch_pkeys_enabled(void)
+{
+	return boot_cpu_has(X86_FEATURE_OSPKE);
+}
+
 /*
  * Try to dedicate one of the protection keys to be used as an
  * execute-only protection key.
@@ -106,4 +111,12 @@ extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
 		unsigned long init_val);
 extern void copy_init_pkru_to_fpregs(void);
 
+static inline int vma_pkey(struct vm_area_struct *vma)
+{
+	unsigned long vma_pkey_mask = VM_PKEY_BIT0 | VM_PKEY_BIT1 |
+				      VM_PKEY_BIT2 | VM_PKEY_BIT3;
+
+	return (vma->vm_flags & vma_pkey_mask) >> VM_PKEY_SHIFT;
+}
+
 #endif /*_ASM_X86_PKEYS_H */
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
@@ -1312,11 +1312,3 @@ static int __init register_kernel_offset_dumper(void)
 	return 0;
 }
 __initcall(register_kernel_offset_dumper);
-
-void arch_show_smap(struct seq_file *m, struct vm_area_struct *vma)
-{
-	if (!boot_cpu_has(X86_FEATURE_OSPKE))
-		return;
-
-	seq_printf(m, "ProtectionKey:  %8u\n", vma_pkey(vma));
-}
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
@@ -18,6 +18,7 @@
 #include <linux/page_idle.h>
 #include <linux/shmem_fs.h>
 #include <linux/uaccess.h>
+#include <linux/pkeys.h>
 
 #include <asm/elf.h>
 #include <asm/tlb.h>
@@ -673,13 +674,16 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 		[ilog2(VM_MERGEABLE)]	= "mg",
 		[ilog2(VM_UFFD_MISSING)]= "um",
 		[ilog2(VM_UFFD_WP)]	= "uw",
-#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
+#ifdef CONFIG_ARCH_HAS_PKEYS
 		/* These come out via ProtectionKey: */
 		[ilog2(VM_PKEY_BIT0)]	= "",
 		[ilog2(VM_PKEY_BIT1)]	= "",
 		[ilog2(VM_PKEY_BIT2)]	= "",
 		[ilog2(VM_PKEY_BIT3)]	= "",
+#if VM_PKEY_BIT4
+		[ilog2(VM_PKEY_BIT4)]	= "",
 #endif
+#endif /* CONFIG_ARCH_HAS_PKEYS */
 	};
 	size_t i;
 
@@ -727,10 +731,6 @@ static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
 }
 #endif /* HUGETLB_PAGE */
 
-void __weak arch_show_smap(struct seq_file *m, struct vm_area_struct *vma)
-{
-}
-
 #define SEQ_PUT_DEC(str, val) \
 		seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
 static int show_smap(struct seq_file *m, void *v, int is_pid)
@@ -835,7 +835,8 @@ static int show_smap(struct seq_file *m, void *v, int is_pid)
 		seq_puts(m, " kB\n");
 	}
 	if (!rollup_mode) {
-		arch_show_smap(m, vma);
+		if (arch_pkeys_enabled())
+			seq_printf(m, "ProtectionKey:  %8u\n", vma_pkey(vma));
 		show_smap_vma_flags(m, vma);
 	}
 	m_cache_vma(m, vma);

diff --git a/include/linux/mm.h b/include/linux/mm.h
@@ -228,15 +228,21 @@ extern unsigned int kobjsize(const void *objp);
 #define VM_HIGH_ARCH_4	BIT(VM_HIGH_ARCH_BIT_4)
 #endif /* CONFIG_ARCH_USES_HIGH_VMA_FLAGS */
 
-#if defined(CONFIG_X86)
-# define VM_PAT		VM_ARCH_1	/* PAT reserves whole VMA at once (x86) */
-#if defined (CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS)
+#ifdef CONFIG_ARCH_HAS_PKEYS
 # define VM_PKEY_SHIFT	VM_HIGH_ARCH_BIT_0
 # define VM_PKEY_BIT0	VM_HIGH_ARCH_0	/* A protection key is a 4-bit value */
-# define VM_PKEY_BIT1	VM_HIGH_ARCH_1
+# define VM_PKEY_BIT1	VM_HIGH_ARCH_1	/* on x86 and 5-bit value on ppc64   */
 # define VM_PKEY_BIT2	VM_HIGH_ARCH_2
 # define VM_PKEY_BIT3	VM_HIGH_ARCH_3
+#ifdef CONFIG_PPC
+# define VM_PKEY_BIT4  VM_HIGH_ARCH_4
+#else
+# define VM_PKEY_BIT4  0
 #endif
+#endif /* CONFIG_ARCH_HAS_PKEYS */
+
+#if defined(CONFIG_X86)
+# define VM_PAT		VM_ARCH_1	/* PAT reserves whole VMA at once (x86) */
 #elif defined(CONFIG_PPC)
 # define VM_SAO		VM_ARCH_1	/* Strong Access Ordering (powerpc) */
 #elif defined(CONFIG_PARISC)

diff --git a/include/linux/pkeys.h b/include/linux/pkeys.h
@@ -2,8 +2,7 @@
 #ifndef _LINUX_PKEYS_H
 #define _LINUX_PKEYS_H
 
-#include <linux/mm_types.h>
-#include <asm/mmu_context.h>
+#include <linux/mm.h>
 
 #ifdef CONFIG_ARCH_HAS_PKEYS
 #include <asm/pkeys.h>
@@ -14,6 +13,11 @@
 #define PKEY_DEDICATED_EXECUTE_ONLY 0
 #define ARCH_VM_PKEY_FLAGS 0
 
+static inline int vma_pkey(struct vm_area_struct *vma)
+{
+	return 0;
+}
+
 static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
 {
 	return (pkey == 0);
@@ -35,6 +39,11 @@ static inline int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
 	return 0;
 }
 
+static inline bool arch_pkeys_enabled(void)
+{
+	return false;
+}
+
 static inline void copy_init_pkru_to_fpregs(void)
 {
 }