[PATCH stable v4.14 00/32] powerpc spectre backports for 4.14

Michael Ellerman mpe at ellerman.id.au
Fri Mar 29 22:25:48 AEDT 2019


-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Hi Greg,

Please queue up these powerpc patches for 4.14 if you have no objections.

cheers


Christophe Leroy (1):
  powerpc/fsl: Fix the flush of branch predictor.

Diana Craciun (16):
  powerpc/64: Disable the speculation barrier from the command line
  powerpc/64: Make stf barrier PPC_BOOK3S_64 specific.
  powerpc/64: Make meltdown reporting Book3S 64 specific
  powerpc/fsl: Add barrier_nospec implementation for NXP PowerPC Book3E
  powerpc/fsl: Sanitize the syscall table for NXP PowerPC 32 bit
    platforms
  powerpc/fsl: Add infrastructure to fixup branch predictor flush
  powerpc/fsl: Add macro to flush the branch predictor
  powerpc/fsl: Fix spectre_v2 mitigations reporting
  powerpc/fsl: Emulate SPRN_BUCSR register
  powerpc/fsl: Add nospectre_v2 command line argument
  powerpc/fsl: Flush the branch predictor at each kernel entry (64bit)
  powerpc/fsl: Flush the branch predictor at each kernel entry (32 bit)
  powerpc/fsl: Flush branch predictor when entering KVM
  powerpc/fsl: Enable runtime patching if nospectre_v2 boot arg is used
  powerpc/fsl: Update Spectre v2 reporting
  powerpc/fsl: Fixed warning: orphan section `__btb_flush_fixup'

Michael Ellerman (11):
  powerpc: Use barrier_nospec in copy_from_user()
  powerpc/64: Use barrier_nospec in syscall entry
  powerpc64s: Show ori31 availability in spectre_v1 sysfs file not v2
  powerpc/64: Add CONFIG_PPC_BARRIER_NOSPEC
  powerpc/64: Call setup_barrier_nospec() from setup_arch()
  powerpc/asm: Add a patch_site macro & helpers for patching
    instructions
  powerpc/64s: Add new security feature flags for count cache flush
  powerpc/64s: Add support for software count cache flush
  powerpc/pseries: Query hypervisor for count cache flush settings
  powerpc/powernv: Query firmware for count cache flush settings
  powerpc/security: Fix spectre_v2 reporting

Michal Suchanek (4):
  powerpc/64s: Add support for ori barrier_nospec patching
  powerpc/64s: Patch barrier_nospec in modules
  powerpc/64s: Enable barrier_nospec based on firmware settings
  powerpc/64s: Enhance the information in cpu_show_spectre_v1()

 arch/powerpc/Kconfig                         |   7 +-
 arch/powerpc/include/asm/asm-prototypes.h    |   6 +
 arch/powerpc/include/asm/barrier.h           |  12 +-
 arch/powerpc/include/asm/code-patching-asm.h |  18 ++
 arch/powerpc/include/asm/code-patching.h     |   2 +
 arch/powerpc/include/asm/feature-fixups.h    |  21 ++
 arch/powerpc/include/asm/hvcall.h            |   2 +
 arch/powerpc/include/asm/ppc_asm.h           |  10 +
 arch/powerpc/include/asm/security_features.h |   7 +
 arch/powerpc/include/asm/setup.h             |  20 ++
 arch/powerpc/include/asm/uaccess.h           |  11 +-
 arch/powerpc/kernel/Makefile                 |   3 +-
 arch/powerpc/kernel/entry_32.S               |  10 +
 arch/powerpc/kernel/entry_64.S               |  69 ++++++
 arch/powerpc/kernel/exceptions-64e.S         |  27 ++-
 arch/powerpc/kernel/head_booke.h             |  12 ++
 arch/powerpc/kernel/head_fsl_booke.S         |  15 ++
 arch/powerpc/kernel/module.c                 |  10 +-
 arch/powerpc/kernel/security.c               | 215 ++++++++++++++++++-
 arch/powerpc/kernel/setup-common.c           |   3 +
 arch/powerpc/kernel/vmlinux.lds.S            |  19 +-
 arch/powerpc/kvm/bookehv_interrupts.S        |   4 +
 arch/powerpc/kvm/e500_emulate.c              |   7 +
 arch/powerpc/lib/code-patching.c             |  16 ++
 arch/powerpc/lib/feature-fixups.c            |  93 ++++++++
 arch/powerpc/mm/tlb_low_64e.S                |   7 +
 arch/powerpc/platforms/powernv/setup.c       |   7 +
 arch/powerpc/platforms/pseries/setup.c       |   7 +
 28 files changed, 622 insertions(+), 18 deletions(-)
 create mode 100644 arch/powerpc/include/asm/code-patching-asm.h

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index fe418226df7f..de3b07c7be30 100644
- --- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -164,7 +164,7 @@ config PPC
 	select GENERIC_CLOCKEVENTS_BROADCAST	if SMP
 	select GENERIC_CMOS_UPDATE
 	select GENERIC_CPU_AUTOPROBE
- -	select GENERIC_CPU_VULNERABILITIES	if PPC_BOOK3S_64
+	select GENERIC_CPU_VULNERABILITIES	if PPC_BARRIER_NOSPEC
 	select GENERIC_IRQ_SHOW
 	select GENERIC_IRQ_SHOW_LEVEL
 	select GENERIC_SMP_IDLE_THREAD
@@ -236,6 +236,11 @@ config PPC
 	# Please keep this list sorted alphabetically.
 	#
 
+config PPC_BARRIER_NOSPEC
+    bool
+    default y
+    depends on PPC_BOOK3S_64 || PPC_FSL_BOOK3E
+
 config GENERIC_CSUM
 	def_bool n
 
diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h
index 7330150bfe34..ba4c75062d49 100644
- --- a/arch/powerpc/include/asm/asm-prototypes.h
+++ b/arch/powerpc/include/asm/asm-prototypes.h
@@ -126,4 +126,10 @@ extern int __ucmpdi2(u64, u64);
 void _mcount(void);
 unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip);
 
+/* Patch sites */
+extern s32 patch__call_flush_count_cache;
+extern s32 patch__flush_count_cache_return;
+
+extern long flush_count_cache;
+
 #endif /* _ASM_POWERPC_ASM_PROTOTYPES_H */
diff --git a/arch/powerpc/include/asm/barrier.h b/arch/powerpc/include/asm/barrier.h
index e582d2c88092..449474f667c4 100644
- --- a/arch/powerpc/include/asm/barrier.h
+++ b/arch/powerpc/include/asm/barrier.h
@@ -77,19 +77,25 @@ do {									\
 })
 
 #ifdef CONFIG_PPC_BOOK3S_64
+#define NOSPEC_BARRIER_SLOT   nop
+#elif defined(CONFIG_PPC_FSL_BOOK3E)
+#define NOSPEC_BARRIER_SLOT   nop; nop
+#endif
+
+#ifdef CONFIG_PPC_BARRIER_NOSPEC
 /*
  * Prevent execution of subsequent instructions until preceding branches have
  * been fully resolved and are no longer executing speculatively.
  */
- -#define barrier_nospec_asm ori 31,31,0
+#define barrier_nospec_asm NOSPEC_BARRIER_FIXUP_SECTION; NOSPEC_BARRIER_SLOT
 
 // This also acts as a compiler barrier due to the memory clobber.
 #define barrier_nospec() asm (stringify_in_c(barrier_nospec_asm) ::: "memory")
 
- -#else /* !CONFIG_PPC_BOOK3S_64 */
+#else /* !CONFIG_PPC_BARRIER_NOSPEC */
 #define barrier_nospec_asm
 #define barrier_nospec()
- -#endif
+#endif /* CONFIG_PPC_BARRIER_NOSPEC */
 
 #include <asm-generic/barrier.h>
 
diff --git a/arch/powerpc/include/asm/code-patching-asm.h b/arch/powerpc/include/asm/code-patching-asm.h
new file mode 100644
index 000000000000..ed7b1448493a
- --- /dev/null
+++ b/arch/powerpc/include/asm/code-patching-asm.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2018, Michael Ellerman, IBM Corporation.
+ */
+#ifndef _ASM_POWERPC_CODE_PATCHING_ASM_H
+#define _ASM_POWERPC_CODE_PATCHING_ASM_H
+
+/* Define a "site" that can be patched */
+.macro patch_site label name
+	.pushsection ".rodata"
+	.balign 4
+	.global \name
+\name:
+	.4byte	\label - .
+	.popsection
+.endm
+
+#endif /* _ASM_POWERPC_CODE_PATCHING_ASM_H */
diff --git a/arch/powerpc/include/asm/code-patching.h b/arch/powerpc/include/asm/code-patching.h
index 812535f40124..b2051234ada8 100644
- --- a/arch/powerpc/include/asm/code-patching.h
+++ b/arch/powerpc/include/asm/code-patching.h
@@ -32,6 +32,8 @@ unsigned int create_cond_branch(const unsigned int *addr,
 int patch_branch(unsigned int *addr, unsigned long target, int flags);
 int patch_instruction(unsigned int *addr, unsigned int instr);
 int raw_patch_instruction(unsigned int *addr, unsigned int instr);
+int patch_instruction_site(s32 *addr, unsigned int instr);
+int patch_branch_site(s32 *site, unsigned long target, int flags);
 
 int instr_is_relative_branch(unsigned int instr);
 int instr_is_relative_link_branch(unsigned int instr);
diff --git a/arch/powerpc/include/asm/feature-fixups.h b/arch/powerpc/include/asm/feature-fixups.h
index a9b64df34e2a..b1d478acbaec 100644
- --- a/arch/powerpc/include/asm/feature-fixups.h
+++ b/arch/powerpc/include/asm/feature-fixups.h
@@ -211,6 +211,25 @@ label##3:					       	\
 	FTR_ENTRY_OFFSET 951b-952b;			\
 	.popsection;
 
+#define NOSPEC_BARRIER_FIXUP_SECTION			\
+953:							\
+	.pushsection __barrier_nospec_fixup,"a";	\
+	.align 2;					\
+954:							\
+	FTR_ENTRY_OFFSET 953b-954b;			\
+	.popsection;
+
+#define START_BTB_FLUSH_SECTION			\
+955:							\
+
+#define END_BTB_FLUSH_SECTION			\
+956:							\
+	.pushsection __btb_flush_fixup,"a";	\
+	.align 2;							\
+957:						\
+	FTR_ENTRY_OFFSET 955b-957b;			\
+	FTR_ENTRY_OFFSET 956b-957b;			\
+	.popsection;
 
 #ifndef __ASSEMBLY__
 #include <linux/types.h>
@@ -219,6 +238,8 @@ extern long stf_barrier_fallback;
 extern long __start___stf_entry_barrier_fixup, __stop___stf_entry_barrier_fixup;
 extern long __start___stf_exit_barrier_fixup, __stop___stf_exit_barrier_fixup;
 extern long __start___rfi_flush_fixup, __stop___rfi_flush_fixup;
+extern long __start___barrier_nospec_fixup, __stop___barrier_nospec_fixup;
+extern long __start__btb_flush_fixup, __stop__btb_flush_fixup;
 
 void apply_feature_fixups(void);
 void setup_feature_keys(void);
diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
index 5a740feb7bd7..15cef59092c7 100644
- --- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -340,10 +340,12 @@
 #define H_CPU_CHAR_BRANCH_HINTS_HONORED	(1ull << 58) // IBM bit 5
 #define H_CPU_CHAR_THREAD_RECONFIG_CTRL	(1ull << 57) // IBM bit 6
 #define H_CPU_CHAR_COUNT_CACHE_DISABLED	(1ull << 56) // IBM bit 7
+#define H_CPU_CHAR_BCCTR_FLUSH_ASSIST	(1ull << 54) // IBM bit 9
 
 #define H_CPU_BEHAV_FAVOUR_SECURITY	(1ull << 63) // IBM bit 0
 #define H_CPU_BEHAV_L1D_FLUSH_PR	(1ull << 62) // IBM bit 1
 #define H_CPU_BEHAV_BNDS_CHK_SPEC_BAR	(1ull << 61) // IBM bit 2
+#define H_CPU_BEHAV_FLUSH_COUNT_CACHE	(1ull << 58) // IBM bit 5
 
 /* Flag values used in H_REGISTER_PROC_TBL hcall */
 #define PROC_TABLE_OP_MASK	0x18
diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h
index 36f3e41c9fbe..3e1b8de72776 100644
- --- a/arch/powerpc/include/asm/ppc_asm.h
+++ b/arch/powerpc/include/asm/ppc_asm.h
@@ -802,4 +802,14 @@ END_FTR_SECTION_IFCLR(CPU_FTR_601)
 	stringify_in_c(.long (_target) - . ;)	\
 	stringify_in_c(.previous)
 
+#ifdef CONFIG_PPC_FSL_BOOK3E
+#define BTB_FLUSH(reg)			\
+	lis reg,BUCSR_INIT at h;		\
+	ori reg,reg,BUCSR_INIT at l;	\
+	mtspr SPRN_BUCSR,reg;		\
+	isync;
+#else
+#define BTB_FLUSH(reg)
+#endif /* CONFIG_PPC_FSL_BOOK3E */
+
 #endif /* _ASM_POWERPC_PPC_ASM_H */
diff --git a/arch/powerpc/include/asm/security_features.h b/arch/powerpc/include/asm/security_features.h
index 44989b22383c..759597bf0fd8 100644
- --- a/arch/powerpc/include/asm/security_features.h
+++ b/arch/powerpc/include/asm/security_features.h
@@ -22,6 +22,7 @@ enum stf_barrier_type {
 
 void setup_stf_barrier(void);
 void do_stf_barrier_fixups(enum stf_barrier_type types);
+void setup_count_cache_flush(void);
 
 static inline void security_ftr_set(unsigned long feature)
 {
@@ -59,6 +60,9 @@ static inline bool security_ftr_enabled(unsigned long feature)
 // Indirect branch prediction cache disabled
 #define SEC_FTR_COUNT_CACHE_DISABLED	0x0000000000000020ull
 
+// bcctr 2,0,0 triggers a hardware assisted count cache flush
+#define SEC_FTR_BCCTR_FLUSH_ASSIST	0x0000000000000800ull
+
 
 // Features indicating need for Spectre/Meltdown mitigations
 
@@ -74,6 +78,9 @@ static inline bool security_ftr_enabled(unsigned long feature)
 // Firmware configuration indicates user favours security over performance
 #define SEC_FTR_FAVOUR_SECURITY		0x0000000000000200ull
 
+// Software required to flush count cache on context switch
+#define SEC_FTR_FLUSH_COUNT_CACHE	0x0000000000000400ull
+
 
 // Features enabled by default
 #define SEC_FTR_DEFAULT \
diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h
index a5e919e34c42..5ceab440ecb9 100644
- --- a/arch/powerpc/include/asm/setup.h
+++ b/arch/powerpc/include/asm/setup.h
@@ -52,6 +52,26 @@ enum l1d_flush_type {
 
 void setup_rfi_flush(enum l1d_flush_type, bool enable);
 void do_rfi_flush_fixups(enum l1d_flush_type types);
+#ifdef CONFIG_PPC_BARRIER_NOSPEC
+void setup_barrier_nospec(void);
+#else
+static inline void setup_barrier_nospec(void) { };
+#endif
+void do_barrier_nospec_fixups(bool enable);
+extern bool barrier_nospec_enabled;
+
+#ifdef CONFIG_PPC_BARRIER_NOSPEC
+void do_barrier_nospec_fixups_range(bool enable, void *start, void *end);
+#else
+static inline void do_barrier_nospec_fixups_range(bool enable, void *start, void *end) { };
+#endif
+
+#ifdef CONFIG_PPC_FSL_BOOK3E
+void setup_spectre_v2(void);
+#else
+static inline void setup_spectre_v2(void) {};
+#endif
+void do_btb_flush_fixups(void);
 
 #endif /* !__ASSEMBLY__ */
 
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index cf26e62b268d..bd6d0fb5be9f 100644
- --- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -238,6 +238,7 @@ do {								\
 	__chk_user_ptr(ptr);					\
 	if (!is_kernel_addr((unsigned long)__gu_addr))		\
 		might_fault();					\
+	barrier_nospec();					\
 	__get_user_size(__gu_val, __gu_addr, (size), __gu_err);	\
 	(x) = (__typeof__(*(ptr)))__gu_val;			\
 	__gu_err;						\
@@ -249,8 +250,10 @@ do {								\
 	__long_type(*(ptr)) __gu_val = 0;				\
 	const __typeof__(*(ptr)) __user *__gu_addr = (ptr);		\
 	might_fault();							\
- -	if (access_ok(VERIFY_READ, __gu_addr, (size)))			\
+	if (access_ok(VERIFY_READ, __gu_addr, (size))) {		\
+		barrier_nospec();					\
 		__get_user_size(__gu_val, __gu_addr, (size), __gu_err);	\
+	}								\
 	(x) = (__force __typeof__(*(ptr)))__gu_val;				\
 	__gu_err;							\
 })
@@ -261,6 +264,7 @@ do {								\
 	__long_type(*(ptr)) __gu_val;				\
 	const __typeof__(*(ptr)) __user *__gu_addr = (ptr);	\
 	__chk_user_ptr(ptr);					\
+	barrier_nospec();					\
 	__get_user_size(__gu_val, __gu_addr, (size), __gu_err);	\
 	(x) = (__force __typeof__(*(ptr)))__gu_val;			\
 	__gu_err;						\
@@ -288,15 +292,19 @@ static inline unsigned long raw_copy_from_user(void *to,
 
 		switch (n) {
 		case 1:
+			barrier_nospec();
 			__get_user_size(*(u8 *)to, from, 1, ret);
 			break;
 		case 2:
+			barrier_nospec();
 			__get_user_size(*(u16 *)to, from, 2, ret);
 			break;
 		case 4:
+			barrier_nospec();
 			__get_user_size(*(u32 *)to, from, 4, ret);
 			break;
 		case 8:
+			barrier_nospec();
 			__get_user_size(*(u64 *)to, from, 8, ret);
 			break;
 		}
@@ -304,6 +312,7 @@ static inline unsigned long raw_copy_from_user(void *to,
 			return 0;
 	}
 
+	barrier_nospec();
 	return __copy_tofrom_user((__force void __user *)to, from, n);
 }
 
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index a1089c9a9aa5..142b08d40642 100644
- --- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -45,9 +45,10 @@ obj-$(CONFIG_VDSO32)		+= vdso32/
 obj-$(CONFIG_PPC_WATCHDOG)	+= watchdog.o
 obj-$(CONFIG_HAVE_HW_BREAKPOINT)	+= hw_breakpoint.o
 obj-$(CONFIG_PPC_BOOK3S_64)	+= cpu_setup_ppc970.o cpu_setup_pa6t.o
- -obj-$(CONFIG_PPC_BOOK3S_64)	+= cpu_setup_power.o security.o
+obj-$(CONFIG_PPC_BOOK3S_64)	+= cpu_setup_power.o
 obj-$(CONFIG_PPC_BOOK3S_64)	+= mce.o mce_power.o
 obj-$(CONFIG_PPC_BOOK3E_64)	+= exceptions-64e.o idle_book3e.o
+obj-$(CONFIG_PPC_BARRIER_NOSPEC) += security.o
 obj-$(CONFIG_PPC64)		+= vdso64/
 obj-$(CONFIG_ALTIVEC)		+= vecemu.o
 obj-$(CONFIG_PPC_970_NAP)	+= idle_power4.o
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 4ae464b9d490..a2999cd73a82 100644
- --- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -33,6 +33,7 @@
 #include <asm/unistd.h>
 #include <asm/ptrace.h>
 #include <asm/export.h>
+#include <asm/barrier.h>
 
 /*
  * MSR_KERNEL is > 0x10000 on 4xx/Book-E since it include MSR_CE.
@@ -358,6 +359,15 @@ _GLOBAL(DoSyscall)
 	ori	r10,r10,sys_call_table at l
 	slwi	r0,r0,2
 	bge-	66f
+
+	barrier_nospec_asm
+	/*
+	 * Prevent the load of the handler below (based on the user-passed
+	 * system call number) being speculatively executed until the test
+	 * against NR_syscalls and branch to .66f above has
+	 * committed.
+	 */
+
 	lwzx	r10,r10,r0	/* Fetch system call handler [ptr] */
 	mtlr	r10
 	addi	r9,r1,STACK_FRAME_OVERHEAD
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index c194f4c8e66b..12395895b9aa 100644
- --- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -25,6 +25,7 @@
 #include <asm/page.h>
 #include <asm/mmu.h>
 #include <asm/thread_info.h>
+#include <asm/code-patching-asm.h>
 #include <asm/ppc_asm.h>
 #include <asm/asm-offsets.h>
 #include <asm/cputable.h>
@@ -36,6 +37,7 @@
 #include <asm/context_tracking.h>
 #include <asm/tm.h>
 #include <asm/ppc-opcode.h>
+#include <asm/barrier.h>
 #include <asm/export.h>
 #ifdef CONFIG_PPC_BOOK3S
 #include <asm/exception-64s.h>
@@ -76,6 +78,11 @@ END_FTR_SECTION_IFSET(CPU_FTR_TM)
 	std	r0,GPR0(r1)
 	std	r10,GPR1(r1)
 	beq	2f			/* if from kernel mode */
+#ifdef CONFIG_PPC_FSL_BOOK3E
+START_BTB_FLUSH_SECTION
+	BTB_FLUSH(r10)
+END_BTB_FLUSH_SECTION
+#endif
 	ACCOUNT_CPU_USER_ENTRY(r13, r10, r11)
 2:	std	r2,GPR2(r1)
 	std	r3,GPR3(r1)
@@ -179,6 +186,15 @@ system_call:			/* label this so stack traces look sane */
 	clrldi	r8,r8,32
 15:
 	slwi	r0,r0,4
+
+	barrier_nospec_asm
+	/*
+	 * Prevent the load of the handler below (based on the user-passed
+	 * system call number) being speculatively executed until the test
+	 * against NR_syscalls and branch to .Lsyscall_enosys above has
+	 * committed.
+	 */
+
 	ldx	r12,r11,r0	/* Fetch system call handler [ptr] */
 	mtctr   r12
 	bctrl			/* Call handler */
@@ -487,6 +503,57 @@ _GLOBAL(ret_from_kernel_thread)
 	li	r3,0
 	b	.Lsyscall_exit
 
+#ifdef CONFIG_PPC_BOOK3S_64
+
+#define FLUSH_COUNT_CACHE	\
+1:	nop;			\
+	patch_site 1b, patch__call_flush_count_cache
+
+
+#define BCCTR_FLUSH	.long 0x4c400420
+
+.macro nops number
+	.rept \number
+	nop
+	.endr
+.endm
+
+.balign 32
+.global flush_count_cache
+flush_count_cache:
+	/* Save LR into r9 */
+	mflr	r9
+
+	.rept 64
+	bl	.+4
+	.endr
+	b	1f
+	nops	6
+
+	.balign 32
+	/* Restore LR */
+1:	mtlr	r9
+	li	r9,0x7fff
+	mtctr	r9
+
+	BCCTR_FLUSH
+
+2:	nop
+	patch_site 2b patch__flush_count_cache_return
+
+	nops	3
+
+	.rept 278
+	.balign 32
+	BCCTR_FLUSH
+	nops	7
+	.endr
+
+	blr
+#else
+#define FLUSH_COUNT_CACHE
+#endif /* CONFIG_PPC_BOOK3S_64 */
+
 /*
  * This routine switches between two different tasks.  The process
  * state of one is saved on its kernel stack.  Then the state
@@ -518,6 +585,8 @@ _GLOBAL(_switch)
 	std	r23,_CCR(r1)
 	std	r1,KSP(r3)	/* Set old stack pointer */
 
+	FLUSH_COUNT_CACHE
+
 	/*
 	 * On SMP kernels, care must be taken because a task may be
 	 * scheduled off CPUx and on to CPUy. Memory ordering must be
diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index acd8ca76233e..2edc1b7b34cc 100644
- --- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -295,7 +295,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
 	andi.	r10,r11,MSR_PR;		/* save stack pointer */	    \
 	beq	1f;			/* branch around if supervisor */   \
 	ld	r1,PACAKSAVE(r13);	/* get kernel stack coming from usr */\
- -1:	cmpdi	cr1,r1,0;		/* check if SP makes sense */	    \
+1:	type##_BTB_FLUSH		\
+	cmpdi	cr1,r1,0;		/* check if SP makes sense */	    \
 	bge-	cr1,exc_##n##_bad_stack;/* bad stack (TODO: out of line) */ \
 	mfspr	r10,SPRN_##type##_SRR0;	/* read SRR0 before touching stack */
 
@@ -327,6 +328,30 @@ END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
 #define SPRN_MC_SRR0	SPRN_MCSRR0
 #define SPRN_MC_SRR1	SPRN_MCSRR1
 
+#ifdef CONFIG_PPC_FSL_BOOK3E
+#define GEN_BTB_FLUSH			\
+	START_BTB_FLUSH_SECTION		\
+		beq 1f;			\
+		BTB_FLUSH(r10)			\
+		1:		\
+	END_BTB_FLUSH_SECTION
+
+#define CRIT_BTB_FLUSH			\
+	START_BTB_FLUSH_SECTION		\
+		BTB_FLUSH(r10)		\
+	END_BTB_FLUSH_SECTION
+
+#define DBG_BTB_FLUSH CRIT_BTB_FLUSH
+#define MC_BTB_FLUSH CRIT_BTB_FLUSH
+#define GDBELL_BTB_FLUSH GEN_BTB_FLUSH
+#else
+#define GEN_BTB_FLUSH
+#define CRIT_BTB_FLUSH
+#define DBG_BTB_FLUSH
+#define MC_BTB_FLUSH
+#define GDBELL_BTB_FLUSH
+#endif
+
 #define NORMAL_EXCEPTION_PROLOG(n, intnum, addition)			    \
 	EXCEPTION_PROLOG(n, intnum, GEN, addition##_GEN(n))
 
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index d0862a100d29..306e26c073a0 100644
- --- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -32,6 +32,16 @@
  */
 #define THREAD_NORMSAVE(offset)	(THREAD_NORMSAVES + (offset * 4))
 
+#ifdef CONFIG_PPC_FSL_BOOK3E
+#define BOOKE_CLEAR_BTB(reg)									\
+START_BTB_FLUSH_SECTION								\
+	BTB_FLUSH(reg)									\
+END_BTB_FLUSH_SECTION
+#else
+#define BOOKE_CLEAR_BTB(reg)
+#endif
+
+
 #define NORMAL_EXCEPTION_PROLOG(intno)						     \
 	mtspr	SPRN_SPRG_WSCRATCH0, r10;	/* save one register */	     \
 	mfspr	r10, SPRN_SPRG_THREAD;					     \
@@ -43,6 +53,7 @@
 	andi.	r11, r11, MSR_PR;	/* check whether user or kernel    */\
 	mr	r11, r1;						     \
 	beq	1f;							     \
+	BOOKE_CLEAR_BTB(r11)						\
 	/* if from user, start at top of this thread's kernel stack */       \
 	lwz	r11, THREAD_INFO-THREAD(r10);				     \
 	ALLOC_STACK_FRAME(r11, THREAD_SIZE);				     \
@@ -128,6 +139,7 @@
 	stw	r9,_CCR(r8);		/* save CR on stack		   */\
 	mfspr	r11,exc_level_srr1;	/* check whether user or kernel    */\
 	DO_KVM	BOOKE_INTERRUPT_##intno exc_level_srr1;		             \
+	BOOKE_CLEAR_BTB(r10)						\
 	andi.	r11,r11,MSR_PR;						     \
 	mfspr	r11,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
 	lwz	r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index bf4c6021515f..60a0aeefc4a7 100644
- --- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -452,6 +452,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
 	mfcr	r13
 	stw	r13, THREAD_NORMSAVE(3)(r10)
 	DO_KVM	BOOKE_INTERRUPT_DTLB_MISS SPRN_SRR1
+START_BTB_FLUSH_SECTION
+	mfspr r11, SPRN_SRR1
+	andi. r10,r11,MSR_PR
+	beq 1f
+	BTB_FLUSH(r10)
+1:
+END_BTB_FLUSH_SECTION
 	mfspr	r10, SPRN_DEAR		/* Get faulting address */
 
 	/* If we are faulting a kernel address, we have to use the
@@ -546,6 +553,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
 	mfcr	r13
 	stw	r13, THREAD_NORMSAVE(3)(r10)
 	DO_KVM	BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR1
+START_BTB_FLUSH_SECTION
+	mfspr r11, SPRN_SRR1
+	andi. r10,r11,MSR_PR
+	beq 1f
+	BTB_FLUSH(r10)
+1:
+END_BTB_FLUSH_SECTION
+
 	mfspr	r10, SPRN_SRR0		/* Get faulting address */
 
 	/* If we are faulting a kernel address, we have to use the
diff --git a/arch/powerpc/kernel/module.c b/arch/powerpc/kernel/module.c
index 3f7ba0f5bf29..77371c9ef3d8 100644
- --- a/arch/powerpc/kernel/module.c
+++ b/arch/powerpc/kernel/module.c
@@ -72,7 +72,15 @@ int module_finalize(const Elf_Ehdr *hdr,
 		do_feature_fixups(powerpc_firmware_features,
 				  (void *)sect->sh_addr,
 				  (void *)sect->sh_addr + sect->sh_size);
- -#endif
+#endif /* CONFIG_PPC64 */
+
+#ifdef CONFIG_PPC_BARRIER_NOSPEC
+	sect = find_section(hdr, sechdrs, "__spec_barrier_fixup");
+	if (sect != NULL)
+		do_barrier_nospec_fixups_range(barrier_nospec_enabled,
+				  (void *)sect->sh_addr,
+				  (void *)sect->sh_addr + sect->sh_size);
+#endif /* CONFIG_PPC_BARRIER_NOSPEC */
 
 	sect = find_section(hdr, sechdrs, "__lwsync_fixup");
 	if (sect != NULL)
diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index b98a722da915..48b50fb8dc4b 100644
- --- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -9,11 +9,120 @@
 #include <linux/seq_buf.h>
 
 #include <asm/debugfs.h>
+#include <asm/asm-prototypes.h>
+#include <asm/code-patching.h>
 #include <asm/security_features.h>
+#include <asm/setup.h>
 
 
 unsigned long powerpc_security_features __read_mostly = SEC_FTR_DEFAULT;
 
+enum count_cache_flush_type {
+	COUNT_CACHE_FLUSH_NONE	= 0x1,
+	COUNT_CACHE_FLUSH_SW	= 0x2,
+	COUNT_CACHE_FLUSH_HW	= 0x4,
+};
+static enum count_cache_flush_type count_cache_flush_type = COUNT_CACHE_FLUSH_NONE;
+
+bool barrier_nospec_enabled;
+static bool no_nospec;
+static bool btb_flush_enabled;
+#ifdef CONFIG_PPC_FSL_BOOK3E
+static bool no_spectrev2;
+#endif
+
+static void enable_barrier_nospec(bool enable)
+{
+	barrier_nospec_enabled = enable;
+	do_barrier_nospec_fixups(enable);
+}
+
+void setup_barrier_nospec(void)
+{
+	bool enable;
+
+	/*
+	 * It would make sense to check SEC_FTR_SPEC_BAR_ORI31 below as well.
+	 * But there's a good reason not to. The two flags we check below are
+	 * both are enabled by default in the kernel, so if the hcall is not
+	 * functional they will be enabled.
+	 * On a system where the host firmware has been updated (so the ori
+	 * functions as a barrier), but on which the hypervisor (KVM/Qemu) has
+	 * not been updated, we would like to enable the barrier. Dropping the
+	 * check for SEC_FTR_SPEC_BAR_ORI31 achieves that. The only downside is
+	 * we potentially enable the barrier on systems where the host firmware
+	 * is not updated, but that's harmless as it's a no-op.
+	 */
+	enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
+		 security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR);
+
+	if (!no_nospec)
+		enable_barrier_nospec(enable);
+}
+
+static int __init handle_nospectre_v1(char *p)
+{
+	no_nospec = true;
+
+	return 0;
+}
+early_param("nospectre_v1", handle_nospectre_v1);
+
+#ifdef CONFIG_DEBUG_FS
+static int barrier_nospec_set(void *data, u64 val)
+{
+	switch (val) {
+	case 0:
+	case 1:
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (!!val == !!barrier_nospec_enabled)
+		return 0;
+
+	enable_barrier_nospec(!!val);
+
+	return 0;
+}
+
+static int barrier_nospec_get(void *data, u64 *val)
+{
+	*val = barrier_nospec_enabled ? 1 : 0;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(fops_barrier_nospec,
+			barrier_nospec_get, barrier_nospec_set, "%llu\n");
+
+static __init int barrier_nospec_debugfs_init(void)
+{
+	debugfs_create_file("barrier_nospec", 0600, powerpc_debugfs_root, NULL,
+			    &fops_barrier_nospec);
+	return 0;
+}
+device_initcall(barrier_nospec_debugfs_init);
+#endif /* CONFIG_DEBUG_FS */
+
+#ifdef CONFIG_PPC_FSL_BOOK3E
+static int __init handle_nospectre_v2(char *p)
+{
+	no_spectrev2 = true;
+
+	return 0;
+}
+early_param("nospectre_v2", handle_nospectre_v2);
+void setup_spectre_v2(void)
+{
+	if (no_spectrev2)
+		do_btb_flush_fixups();
+	else
+		btb_flush_enabled = true;
+}
+#endif /* CONFIG_PPC_FSL_BOOK3E */
+
+#ifdef CONFIG_PPC_BOOK3S_64
 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
 {
 	bool thread_priv;
@@ -46,25 +155,39 @@ ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, cha
 
 	return sprintf(buf, "Vulnerable\n");
 }
+#endif
 
 ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, char *buf)
 {
- -	if (!security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR))
- -		return sprintf(buf, "Not affected\n");
+	struct seq_buf s;
 
- -	return sprintf(buf, "Vulnerable\n");
+	seq_buf_init(&s, buf, PAGE_SIZE - 1);
+
+	if (security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR)) {
+		if (barrier_nospec_enabled)
+			seq_buf_printf(&s, "Mitigation: __user pointer sanitization");
+		else
+			seq_buf_printf(&s, "Vulnerable");
+
+		if (security_ftr_enabled(SEC_FTR_SPEC_BAR_ORI31))
+			seq_buf_printf(&s, ", ori31 speculation barrier enabled");
+
+		seq_buf_printf(&s, "\n");
+	} else
+		seq_buf_printf(&s, "Not affected\n");
+
+	return s.len;
 }
 
 ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, char *buf)
 {
- -	bool bcs, ccd, ori;
 	struct seq_buf s;
+	bool bcs, ccd;
 
 	seq_buf_init(&s, buf, PAGE_SIZE - 1);
 
 	bcs = security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED);
 	ccd = security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED);
- -	ori = security_ftr_enabled(SEC_FTR_SPEC_BAR_ORI31);
 
 	if (bcs || ccd) {
 		seq_buf_printf(&s, "Mitigation: ");
@@ -77,17 +200,23 @@ ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, c
 
 		if (ccd)
 			seq_buf_printf(&s, "Indirect branch cache disabled");
- -	} else
+	} else if (count_cache_flush_type != COUNT_CACHE_FLUSH_NONE) {
+		seq_buf_printf(&s, "Mitigation: Software count cache flush");
+
+		if (count_cache_flush_type == COUNT_CACHE_FLUSH_HW)
+			seq_buf_printf(&s, " (hardware accelerated)");
+	} else if (btb_flush_enabled) {
+		seq_buf_printf(&s, "Mitigation: Branch predictor state flush");
+	} else {
 		seq_buf_printf(&s, "Vulnerable");
- -
- -	if (ori)
- -		seq_buf_printf(&s, ", ori31 speculation barrier enabled");
+	}
 
 	seq_buf_printf(&s, "\n");
 
 	return s.len;
 }
 
+#ifdef CONFIG_PPC_BOOK3S_64
 /*
  * Store-forwarding barrier support.
  */
@@ -235,3 +364,71 @@ static __init int stf_barrier_debugfs_init(void)
 }
 device_initcall(stf_barrier_debugfs_init);
 #endif /* CONFIG_DEBUG_FS */
+
+static void toggle_count_cache_flush(bool enable)
+{
+	if (!enable || !security_ftr_enabled(SEC_FTR_FLUSH_COUNT_CACHE)) {
+		patch_instruction_site(&patch__call_flush_count_cache, PPC_INST_NOP);
+		count_cache_flush_type = COUNT_CACHE_FLUSH_NONE;
+		pr_info("count-cache-flush: software flush disabled.\n");
+		return;
+	}
+
+	patch_branch_site(&patch__call_flush_count_cache,
+			  (u64)&flush_count_cache, BRANCH_SET_LINK);
+
+	if (!security_ftr_enabled(SEC_FTR_BCCTR_FLUSH_ASSIST)) {
+		count_cache_flush_type = COUNT_CACHE_FLUSH_SW;
+		pr_info("count-cache-flush: full software flush sequence enabled.\n");
+		return;
+	}
+
+	patch_instruction_site(&patch__flush_count_cache_return, PPC_INST_BLR);
+	count_cache_flush_type = COUNT_CACHE_FLUSH_HW;
+	pr_info("count-cache-flush: hardware assisted flush sequence enabled\n");
+}
+
+void setup_count_cache_flush(void)
+{
+	toggle_count_cache_flush(true);
+}
+
+#ifdef CONFIG_DEBUG_FS
+static int count_cache_flush_set(void *data, u64 val)
+{
+	bool enable;
+
+	if (val == 1)
+		enable = true;
+	else if (val == 0)
+		enable = false;
+	else
+		return -EINVAL;
+
+	toggle_count_cache_flush(enable);
+
+	return 0;
+}
+
+static int count_cache_flush_get(void *data, u64 *val)
+{
+	if (count_cache_flush_type == COUNT_CACHE_FLUSH_NONE)
+		*val = 0;
+	else
+		*val = 1;
+
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(fops_count_cache_flush, count_cache_flush_get,
+			count_cache_flush_set, "%llu\n");
+
+static __init int count_cache_flush_debugfs_init(void)
+{
+	debugfs_create_file("count_cache_flush", 0600, powerpc_debugfs_root,
+			    NULL, &fops_count_cache_flush);
+	return 0;
+}
+device_initcall(count_cache_flush_debugfs_init);
+#endif /* CONFIG_DEBUG_FS */
+#endif /* CONFIG_PPC_BOOK3S_64 */
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index 008447664643..c58364c74dad 100644
- --- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -937,6 +937,9 @@ void __init setup_arch(char **cmdline_p)
 	if (ppc_md.setup_arch)
 		ppc_md.setup_arch();
 
+	setup_barrier_nospec();
+	setup_spectre_v2();
+
 	paging_init();
 
 	/* Initialize the MMU context management stuff. */
diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index c89ffb88fa3b..b0cf4af7ba84 100644
- --- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -153,8 +153,25 @@ SECTIONS
 		*(__rfi_flush_fixup)
 		__stop___rfi_flush_fixup = .;
 	}
- -#endif
+#endif /* CONFIG_PPC64 */
+
+#ifdef CONFIG_PPC_BARRIER_NOSPEC
+	. = ALIGN(8);
+	__spec_barrier_fixup : AT(ADDR(__spec_barrier_fixup) - LOAD_OFFSET) {
+		__start___barrier_nospec_fixup = .;
+		*(__barrier_nospec_fixup)
+		__stop___barrier_nospec_fixup = .;
+	}
+#endif /* CONFIG_PPC_BARRIER_NOSPEC */
 
+#ifdef CONFIG_PPC_FSL_BOOK3E
+	. = ALIGN(8);
+	__spec_btb_flush_fixup : AT(ADDR(__spec_btb_flush_fixup) - LOAD_OFFSET) {
+		__start__btb_flush_fixup = .;
+		*(__btb_flush_fixup)
+		__stop__btb_flush_fixup = .;
+	}
+#endif
 	EXCEPTION_TABLE(0)
 
 	NOTES :kernel :notes
diff --git a/arch/powerpc/kvm/bookehv_interrupts.S b/arch/powerpc/kvm/bookehv_interrupts.S
index 81bd8a07aa51..612b7f6a887f 100644
- --- a/arch/powerpc/kvm/bookehv_interrupts.S
+++ b/arch/powerpc/kvm/bookehv_interrupts.S
@@ -75,6 +75,10 @@
 	PPC_LL	r1, VCPU_HOST_STACK(r4)
 	PPC_LL	r2, HOST_R2(r1)
 
+START_BTB_FLUSH_SECTION
+	BTB_FLUSH(r10)
+END_BTB_FLUSH_SECTION
+
 	mfspr	r10, SPRN_PID
 	lwz	r8, VCPU_HOST_PID(r4)
 	PPC_LL	r11, VCPU_SHARED(r4)
diff --git a/arch/powerpc/kvm/e500_emulate.c b/arch/powerpc/kvm/e500_emulate.c
index 990db69a1d0b..fa88f641ac03 100644
- --- a/arch/powerpc/kvm/e500_emulate.c
+++ b/arch/powerpc/kvm/e500_emulate.c
@@ -277,6 +277,13 @@ int kvmppc_core_emulate_mtspr_e500(struct kvm_vcpu *vcpu, int sprn, ulong spr_va
 		vcpu->arch.pwrmgtcr0 = spr_val;
 		break;
 
+	case SPRN_BUCSR:
+		/*
+		 * If we are here, it means that we have already flushed the
+		 * branch predictor, so just return to guest.
+		 */
+		break;
+
 	/* extra exceptions */
 #ifdef CONFIG_SPE_POSSIBLE
 	case SPRN_IVOR32:
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index 130405158afa..c5154817178b 100644
- --- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -206,6 +206,22 @@ int patch_branch(unsigned int *addr, unsigned long target, int flags)
 	return patch_instruction(addr, create_branch(addr, target, flags));
 }
 
+int patch_branch_site(s32 *site, unsigned long target, int flags)
+{
+	unsigned int *addr;
+
+	addr = (unsigned int *)((unsigned long)site + *site);
+	return patch_instruction(addr, create_branch(addr, target, flags));
+}
+
+int patch_instruction_site(s32 *site, unsigned int instr)
+{
+	unsigned int *addr;
+
+	addr = (unsigned int *)((unsigned long)site + *site);
+	return patch_instruction(addr, instr);
+}
+
 bool is_offset_in_branch_range(long offset)
 {
 	/*
diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c
index e1bcdc32a851..de7861e09b41 100644
- --- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -277,8 +277,101 @@ void do_rfi_flush_fixups(enum l1d_flush_type types)
 		(types &  L1D_FLUSH_MTTRIG)     ? "mttrig type"
 						: "unknown");
 }
+
+void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end)
+{
+	unsigned int instr, *dest;
+	long *start, *end;
+	int i;
+
+	start = fixup_start;
+	end = fixup_end;
+
+	instr = 0x60000000; /* nop */
+
+	if (enable) {
+		pr_info("barrier-nospec: using ORI speculation barrier\n");
+		instr = 0x63ff0000; /* ori 31,31,0 speculation barrier */
+	}
+
+	for (i = 0; start < end; start++, i++) {
+		dest = (void *)start + *start;
+
+		pr_devel("patching dest %lx\n", (unsigned long)dest);
+		patch_instruction(dest, instr);
+	}
+
+	printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i);
+}
+
 #endif /* CONFIG_PPC_BOOK3S_64 */
 
+#ifdef CONFIG_PPC_BARRIER_NOSPEC
+void do_barrier_nospec_fixups(bool enable)
+{
+	void *start, *end;
+
+	start = PTRRELOC(&__start___barrier_nospec_fixup),
+	end = PTRRELOC(&__stop___barrier_nospec_fixup);
+
+	do_barrier_nospec_fixups_range(enable, start, end);
+}
+#endif /* CONFIG_PPC_BARRIER_NOSPEC */
+
+#ifdef CONFIG_PPC_FSL_BOOK3E
+void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end)
+{
+	unsigned int instr[2], *dest;
+	long *start, *end;
+	int i;
+
+	start = fixup_start;
+	end = fixup_end;
+
+	instr[0] = PPC_INST_NOP;
+	instr[1] = PPC_INST_NOP;
+
+	if (enable) {
+		pr_info("barrier-nospec: using isync; sync as speculation barrier\n");
+		instr[0] = PPC_INST_ISYNC;
+		instr[1] = PPC_INST_SYNC;
+	}
+
+	for (i = 0; start < end; start++, i++) {
+		dest = (void *)start + *start;
+
+		pr_devel("patching dest %lx\n", (unsigned long)dest);
+		patch_instruction(dest, instr[0]);
+		patch_instruction(dest + 1, instr[1]);
+	}
+
+	printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i);
+}
+
+static void patch_btb_flush_section(long *curr)
+{
+	unsigned int *start, *end;
+
+	start = (void *)curr + *curr;
+	end = (void *)curr + *(curr + 1);
+	for (; start < end; start++) {
+		pr_devel("patching dest %lx\n", (unsigned long)start);
+		patch_instruction(start, PPC_INST_NOP);
+	}
+}
+
+void do_btb_flush_fixups(void)
+{
+	long *start, *end;
+
+	start = PTRRELOC(&__start__btb_flush_fixup);
+	end = PTRRELOC(&__stop__btb_flush_fixup);
+
+	for (; start < end; start += 2)
+		patch_btb_flush_section(start);
+}
+#endif /* CONFIG_PPC_FSL_BOOK3E */
+
 void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end)
 {
 	long *start, *end;
diff --git a/arch/powerpc/mm/tlb_low_64e.S b/arch/powerpc/mm/tlb_low_64e.S
index eb82d787d99a..b7e9c09dfe19 100644
- --- a/arch/powerpc/mm/tlb_low_64e.S
+++ b/arch/powerpc/mm/tlb_low_64e.S
@@ -69,6 +69,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
 	std	r15,EX_TLB_R15(r12)
 	std	r10,EX_TLB_CR(r12)
 #ifdef CONFIG_PPC_FSL_BOOK3E
+START_BTB_FLUSH_SECTION
+	mfspr r11, SPRN_SRR1
+	andi. r10,r11,MSR_PR
+	beq 1f
+	BTB_FLUSH(r10)
+1:
+END_BTB_FLUSH_SECTION
 	std	r7,EX_TLB_R7(r12)
 #endif
 	TLB_MISS_PROLOG_STATS
diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index fd143c934768..888aa9584e94 100644
- --- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -77,6 +77,12 @@ static void init_fw_feat_flags(struct device_node *np)
 	if (fw_feature_is("enabled", "fw-count-cache-disabled", np))
 		security_ftr_set(SEC_FTR_COUNT_CACHE_DISABLED);
 
+	if (fw_feature_is("enabled", "fw-count-cache-flush-bcctr2,0,0", np))
+		security_ftr_set(SEC_FTR_BCCTR_FLUSH_ASSIST);
+
+	if (fw_feature_is("enabled", "needs-count-cache-flush-on-context-switch", np))
+		security_ftr_set(SEC_FTR_FLUSH_COUNT_CACHE);
+
 	/*
 	 * The features below are enabled by default, so we instead look to see
 	 * if firmware has *disabled* them, and clear them if so.
@@ -123,6 +129,7 @@ static void pnv_setup_rfi_flush(void)
 		  security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV));
 
 	setup_rfi_flush(type, enable);
+	setup_count_cache_flush();
 }
 
 static void __init pnv_setup_arch(void)
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 45f814041448..6a0ad56e89b9 100644
- --- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -484,6 +484,12 @@ static void init_cpu_char_feature_flags(struct h_cpu_char_result *result)
 	if (result->character & H_CPU_CHAR_COUNT_CACHE_DISABLED)
 		security_ftr_set(SEC_FTR_COUNT_CACHE_DISABLED);
 
+	if (result->character & H_CPU_CHAR_BCCTR_FLUSH_ASSIST)
+		security_ftr_set(SEC_FTR_BCCTR_FLUSH_ASSIST);
+
+	if (result->behaviour & H_CPU_BEHAV_FLUSH_COUNT_CACHE)
+		security_ftr_set(SEC_FTR_FLUSH_COUNT_CACHE);
+
 	/*
 	 * The features below are enabled by default, so we instead look to see
 	 * if firmware has *disabled* them, and clear them if so.
@@ -534,6 +540,7 @@ void pseries_setup_rfi_flush(void)
 		 security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR);
 
 	setup_rfi_flush(types, enable);
+	setup_count_cache_flush();
 }
 
 static void __init pSeries_setup_arch(void)
- -- 
2.20.1

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