diff mbox series

[v5,03/23] powerpc/book3s64/kuap/kuep: Make KUAP and KUEP a subfeature of PPC_MEM_KEYS

Message ID 20200827040931.297759-4-aneesh.kumar@linux.ibm.com (mailing list archive)
State Superseded
Headers show
Series Kernel userspace access/execution prevention with hash translation | expand

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Context Check Description
snowpatch_ozlabs/apply_patch success Successfully applied on branch powerpc/merge (d4ecce4dcc8f8820286cf4e0859850c555e89854)
snowpatch_ozlabs/checkpatch success total: 0 errors, 0 warnings, 0 checks, 156 lines checked
snowpatch_ozlabs/needsstable success Patch has no Fixes tags

Commit Message

Aneesh Kumar K V Aug. 27, 2020, 4:09 a.m. UTC
The next set of patches adds support for kuap with hash translation.
Hence make KUAP a BOOK3S_64 feature. Also make it a subfeature of
PPC_MEM_KEYS. Hash translation is going to use pkeys to support
KUAP/KUEP. Adding this dependency reduces the code complexity and
enables us to move some of the initialization code to pkeys.c

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
 .../powerpc/include/asm/book3s/64/kup-radix.h | 33 +++++++++++--------
 arch/powerpc/include/asm/book3s/64/mmu.h      |  2 +-
 arch/powerpc/include/asm/ptrace.h             |  2 +-
 arch/powerpc/kernel/asm-offsets.c             |  2 +-
 arch/powerpc/mm/book3s64/Makefile             |  2 +-
 arch/powerpc/mm/book3s64/pkeys.c              | 24 +++++++++-----
 arch/powerpc/platforms/Kconfig.cputype        |  4 +++
 7 files changed, 42 insertions(+), 27 deletions(-)
diff mbox series

Patch

diff --git a/arch/powerpc/include/asm/book3s/64/kup-radix.h b/arch/powerpc/include/asm/book3s/64/kup-radix.h
index 3ee1ec60be84..19a8e640a4e5 100644
--- a/arch/powerpc/include/asm/book3s/64/kup-radix.h
+++ b/arch/powerpc/include/asm/book3s/64/kup-radix.h
@@ -61,7 +61,7 @@ 
 
 #else /* !__ASSEMBLY__ */
 
-#ifdef CONFIG_PPC_KUAP
+#ifdef CONFIG_PPC_PKEY
 
 #include <asm/mmu.h>
 #include <asm/ptrace.h>
@@ -96,6 +96,24 @@  static inline void kuap_check_amr(void)
 		WARN_ON_ONCE(mfspr(SPRN_AMR) != AMR_KUAP_BLOCKED);
 }
 
+#else /* CONFIG_PPC_PKEY */
+
+static inline void kuap_restore_amr(struct pt_regs *regs, unsigned long amr)
+{
+}
+
+static inline void kuap_check_amr(void)
+{
+}
+
+static inline unsigned long kuap_get_and_check_amr(void)
+{
+	return 0;
+}
+#endif /* CONFIG_PPC_PKEY */
+
+
+#ifdef CONFIG_PPC_KUAP
 /*
  * We support individually allowing read or write, but we don't support nesting
  * because that would require an expensive read/modify write of the AMR.
@@ -165,19 +183,6 @@  bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
 		    (regs->kuap & (is_write ? AMR_KUAP_BLOCK_WRITE : AMR_KUAP_BLOCK_READ)),
 		    "Bug: %s fault blocked by AMR!", is_write ? "Write" : "Read");
 }
-#else /* CONFIG_PPC_KUAP */
-static inline void kuap_restore_amr(struct pt_regs *regs, unsigned long amr)
-{
-}
-
-static inline void kuap_check_amr(void)
-{
-}
-
-static inline unsigned long kuap_get_and_check_amr(void)
-{
-	return 0;
-}
 #endif /* CONFIG_PPC_KUAP */
 
 #endif /* __ASSEMBLY__ */
diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
index 55442d45c597..381146afaf80 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu.h
@@ -214,7 +214,7 @@  extern int mmu_io_psize;
 void mmu_early_init_devtree(void);
 void hash__early_init_devtree(void);
 void radix__early_init_devtree(void);
-#ifdef CONFIG_PPC_MEM_KEYS
+#ifdef CONFIG_PPC_PKEY
 void pkey_early_init_devtree(void);
 #else
 static inline void pkey_early_init_devtree(void) {}
diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index 155a197c0aa1..5f62ce579a8b 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -53,7 +53,7 @@  struct pt_regs
 #ifdef CONFIG_PPC64
 			unsigned long ppr;
 #endif
-#ifdef CONFIG_PPC_KUAP
+#ifdef CONFIG_PPC_PKEY
 			unsigned long kuap;
 #endif
 		};
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 8711c2164b45..63548992b5ab 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -353,7 +353,7 @@  int main(void)
 	STACK_PT_REGS_OFFSET(_PPR, ppr);
 #endif /* CONFIG_PPC64 */
 
-#ifdef CONFIG_PPC_KUAP
+#ifdef CONFIG_PPC_PKEY
 	STACK_PT_REGS_OFFSET(STACK_REGS_KUAP, kuap);
 #endif
 
diff --git a/arch/powerpc/mm/book3s64/Makefile b/arch/powerpc/mm/book3s64/Makefile
index fd393b8be14f..1b56d3af47d4 100644
--- a/arch/powerpc/mm/book3s64/Makefile
+++ b/arch/powerpc/mm/book3s64/Makefile
@@ -17,7 +17,7 @@  endif
 obj-$(CONFIG_TRANSPARENT_HUGEPAGE) += hash_hugepage.o
 obj-$(CONFIG_PPC_SUBPAGE_PROT)	+= subpage_prot.o
 obj-$(CONFIG_SPAPR_TCE_IOMMU)	+= iommu_api.o
-obj-$(CONFIG_PPC_MEM_KEYS)	+= pkeys.o
+obj-$(CONFIG_PPC_PKEY)	+= pkeys.o
 
 # Instrumenting the SLB fault path can lead to duplicate SLB entries
 KCOV_INSTRUMENT_slb.o := n
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index b1d091a97611..7dc71f85683d 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -89,12 +89,14 @@  static int scan_pkey_feature(void)
 		}
 	}
 
+#ifdef CONFIG_PPC_MEM_KEYS
 	/*
 	 * Adjust the upper limit, based on the number of bits supported by
 	 * arch-neutral code.
 	 */
 	pkeys_total = min_t(int, pkeys_total,
 			    ((ARCH_VM_PKEY_FLAGS >> VM_PKEY_SHIFT) + 1));
+#endif
 	return pkeys_total;
 }
 
@@ -102,6 +104,7 @@  void __init pkey_early_init_devtree(void)
 {
 	int pkeys_total, i;
 
+#ifdef CONFIG_PPC_MEM_KEYS
 	/*
 	 * We define PKEY_DISABLE_EXECUTE in addition to the arch-neutral
 	 * generic defines for PKEY_DISABLE_ACCESS and PKEY_DISABLE_WRITE.
@@ -117,7 +120,7 @@  void __init pkey_early_init_devtree(void)
 	BUILD_BUG_ON(__builtin_clzl(ARCH_VM_PKEY_FLAGS >> VM_PKEY_SHIFT) +
 		     __builtin_popcountl(ARCH_VM_PKEY_FLAGS >> VM_PKEY_SHIFT)
 				!= (sizeof(u64) * BITS_PER_BYTE));
-
+#endif
 	/*
 	 * Only P7 and above supports SPRN_AMR update with MSR[PR] = 1
 	 */
@@ -223,14 +226,6 @@  void __init pkey_early_init_devtree(void)
 	return;
 }
 
-void pkey_mm_init(struct mm_struct *mm)
-{
-	if (!mmu_has_feature(MMU_FTR_PKEY))
-		return;
-	mm_pkey_allocation_map(mm) = initial_allocation_mask;
-	mm->context.execute_only_pkey = execute_only_key;
-}
-
 static inline u64 read_amr(void)
 {
 	return mfspr(SPRN_AMR);
@@ -257,6 +252,15 @@  static inline void write_iamr(u64 value)
 	mtspr(SPRN_IAMR, value);
 }
 
+#ifdef CONFIG_PPC_MEM_KEYS
+void pkey_mm_init(struct mm_struct *mm)
+{
+	if (!mmu_has_feature(MMU_FTR_PKEY))
+		return;
+	mm_pkey_allocation_map(mm) = initial_allocation_mask;
+	mm->context.execute_only_pkey = execute_only_key;
+}
+
 static inline void init_amr(int pkey, u8 init_bits)
 {
 	u64 new_amr_bits = (((u64)init_bits & 0x3UL) << pkeyshift(pkey));
@@ -445,3 +449,5 @@  void arch_dup_pkeys(struct mm_struct *oldmm, struct mm_struct *mm)
 	mm_pkey_allocation_map(mm) = mm_pkey_allocation_map(oldmm);
 	mm->context.execute_only_pkey = oldmm->context.execute_only_pkey;
 }
+
+#endif /* CONFIG_PPC_MEM_KEYS */
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 87737ec86d39..59d773c244ec 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -402,6 +402,10 @@  config PPC_KUAP_DEBUG
 	  Add extra debugging for Kernel Userspace Access Protection (KUAP)
 	  If you're unsure, say N.
 
+config PPC_PKEY
+	def_bool y
+	depends on PPC_MEM_KEYS || PPC_KUAP || PPC_KUEP
+
 config ARCH_ENABLE_HUGEPAGE_MIGRATION
 	def_bool y
 	depends on PPC_BOOK3S_64 && HUGETLB_PAGE && MIGRATION