Merge android-4.4.113 (ef588ef) into msm-4.4

* refs/heads/tmp-ef588ef
  Linux 4.4.113
  MIPS: AR7: ensure the port type's FCR value is used
  x86/retpoline: Optimize inline assembler for vmexit_fill_RSB
  x86/pti: Document fix wrong index
  kprobes/x86: Disable optimizing on the function jumps to indirect thunk
  kprobes/x86: Blacklist indirect thunk functions for kprobes
  retpoline: Introduce start/end markers of indirect thunk
  x86/mce: Make machine check speculation protected
  kbuild: modversions for EXPORT_SYMBOL() for asm
  x86/cpu, x86/pti: Do not enable PTI on AMD processors
  arm64: KVM: Fix SMCCC handling of unimplemented SMC/HVC calls
  dm thin metadata: THIN_MAX_CONCURRENT_LOCKS should be 6
  dm btree: fix serious bug in btree_split_beneath()
  libata: apply MAX_SEC_1024 to all LITEON EP1 series devices
  can: peak: fix potential bug in packet fragmentation
  ARM: dts: kirkwood: fix pin-muxing of MPP7 on OpenBlocks A7
  phy: work around 'phys' references to usb-nop-xceiv devices
  tracing: Fix converting enum's from the map in trace_event_eval_update()
  Input: twl4030-vibra - fix sibling-node lookup
  Input: twl6040-vibra - fix child-node lookup
  Input: twl6040-vibra - fix DT node memory management
  Input: 88pm860x-ts - fix child-node lookup
  x86/apic/vector: Fix off by one in error path
  pipe: avoid round_pipe_size() nr_pages overflow on 32-bit
  module: Add retpoline tag to VERMAGIC
  x86/retpoline: Add LFENCE to the retpoline/RSB filling RSB macros
  sched/deadline: Zero out positive runtime after throttling constrained tasks
  scsi: hpsa: fix volume offline state
  af_key: fix buffer overread in parse_exthdrs()
  af_key: fix buffer overread in verify_address_len()
  ALSA: hda - Apply the existing quirk to iMac 14,1
  ALSA: hda - Apply headphone noise quirk for another Dell XPS 13 variant
  ALSA: pcm: Remove yet superfluous WARN_ON()
  futex: Prevent overflow by strengthen input validation
  scsi: sg: disable SET_FORCE_LOW_DMA
  x86/retpoline: Remove compile time warning
  x86/retpoline: Fill return stack buffer on vmexit
  x86/retpoline/irq32: Convert assembler indirect jumps
  x86/retpoline/checksum32: Convert assembler indirect jumps
  x86/retpoline/xen: Convert Xen hypercall indirect jumps
  x86/retpoline/hyperv: Convert assembler indirect jumps
  x86/retpoline/ftrace: Convert ftrace assembler indirect jumps
  x86/retpoline/entry: Convert entry assembler indirect jumps
  x86/retpoline/crypto: Convert crypto assembler indirect jumps
  x86/spectre: Add boot time option to select Spectre v2 mitigation
  x86/retpoline: Add initial retpoline support
  kconfig.h: use __is_defined() to check if MODULE is defined
  EXPORT_SYMBOL() for asm
  x86/asm: Make asm/alternative.h safe from assembly
  x86/kbuild: enable modversions for symbols exported from asm
  x86/asm: Use register variable to get stack pointer value
  x86/mm/32: Move setup_clear_cpu_cap(X86_FEATURE_PCID) earlier
  x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC
  x86/cpu/AMD: Make LFENCE a serializing instruction
  gcov: disable for COMPILE_TEST
  ANDROID: sdcardfs: Move default_normal to superblock
  blkdev: Refactoring block io latency histogram codes
  FROMLIST: arm64: kpti: Fix the interaction between ASID switching and software PAN
  FROMLIST: arm64: Move post_ttbr_update_workaround to C code
  FROMLIST: arm64: mm: Rename post_ttbr0_update_workaround
  sched: EAS: Initialize push_task as NULL to avoid direct reference on out_unlock path

Conflicts:
	arch/arm64/include/asm/efi.h
	arch/arm64/include/asm/mmu_context.h
	drivers/scsi/sg.c
	drivers/scsi/ufs/ufshcd.h

Change-Id: Ibfa06af8ef308077aad6995874d4b7b0a73e95f3
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>

4 files changed, 23 insertions, 27 deletions

diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
index 0e67a507dfbc..a217fab3f4ba 100644
--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -410,17 +410,4 @@ alternative_endif
 	mrs	\rd, sp_el0
 	.endm
 
-/*
- * Errata workaround post TTBR0_EL1 update.
- */
-	.macro	post_ttbr0_update_workaround
-#ifdef CONFIG_CAVIUM_ERRATUM_27456
-alternative_if ARM64_WORKAROUND_CAVIUM_27456
-	ic	iallu
-	dsb	nsh
-	isb
-alternative_else_nop_endif
-#endif
-	.endm
-
 #endif	/* __ASM_ASSEMBLER_H */
diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h
index b7406e05056b..5da584a14808 100644
--- a/arch/arm64/include/asm/efi.h
+++ b/arch/arm64/include/asm/efi.h
@@ -76,19 +76,21 @@ static inline void efi_set_pgd(struct mm_struct *mm)
 		if (mm != current->active_mm) {
 			/*
 			 * Update the current thread's saved ttbr0 since it is
-			 * restored as part of a return from exception. Set
-			 * the hardware TTBR0_EL1 using cpu_switch_mm()
-			 * directly to enable potential errata workarounds.
+			 * restored as part of a return from exception. Enable
+			 * access to the valid TTBR0_EL1 and invoke the errata
+			 * workaround directly since there is no return from
+			 * exception when invoking the EFI run-time services.
 			 */
 			update_saved_ttbr0(current, mm);
-			cpu_switch_mm(mm->pgd, mm);
+			uaccess_ttbr0_enable();
+			post_ttbr_update_workaround();
 		} else {
 			/*
 			 * Defer the switch to the current thread's TTBR0_EL1
 			 * until uaccess_enable(). Restore the current
 			 * thread's saved ttbr0 corresponding to its active_mm
 			 */
-			cpu_set_reserved_ttbr0();
+			uaccess_ttbr0_disable();
 			update_saved_ttbr0(current, current->active_mm);
 		}
 	}
diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h
index e4405cfd0ed1..17d0ada5b473 100644
--- a/arch/arm64/include/asm/mmu_context.h
+++ b/arch/arm64/include/asm/mmu_context.h
@@ -186,7 +186,7 @@ static inline void update_saved_ttbr0(struct task_struct *tsk,
 	else
 		ttbr = virt_to_phys(mm->pgd) | ASID(mm) << 48;
 
-	task_thread_info(tsk)->ttbr0 = ttbr;
+	WRITE_ONCE(task_thread_info(tsk)->ttbr0, ttbr);
 }
 #else
 static inline void update_saved_ttbr0(struct task_struct *tsk,
@@ -240,4 +240,6 @@ switch_mm(struct mm_struct *prev, struct mm_struct *next,
 #define deactivate_mm(tsk,mm)	do { } while (0)
 #define activate_mm(prev,next)	switch_mm(prev, next, current)
 
+void post_ttbr_update_workaround(void);
+
 #endif
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h
index 57c4bbdf77cc..d39d8bde42d7 100644
--- a/arch/arm64/include/asm/uaccess.h
+++ b/arch/arm64/include/asm/uaccess.h
@@ -143,16 +143,18 @@ static inline void set_fs(mm_segment_t fs)
 #ifdef CONFIG_ARM64_SW_TTBR0_PAN
 static inline void __uaccess_ttbr0_disable(void)
 {
-	unsigned long ttbr;
+	unsigned long flags, ttbr;
 
+	local_irq_save(flags);
 	ttbr = read_sysreg(ttbr1_el1);
+	ttbr &= ~TTBR_ASID_MASK;
 	/* reserved_ttbr0 placed at the end of swapper_pg_dir */
 	write_sysreg(ttbr + SWAPPER_DIR_SIZE, ttbr0_el1);
 	isb();
 	/* Set reserved ASID */
-	ttbr &= ~TTBR_ASID_MASK;
 	write_sysreg(ttbr, ttbr1_el1);
 	isb();
+	local_irq_restore(flags);
 }
 
 static inline void __uaccess_ttbr0_enable(void)
@@ -165,10 +167,11 @@ static inline void __uaccess_ttbr0_enable(void)
 	 * roll-over and an update of 'ttbr0'.
 	 */
 	local_irq_save(flags);
-	ttbr0 = current_thread_info()->ttbr0;
+	ttbr0 = READ_ONCE(current_thread_info()->ttbr0);
 
 	/* Restore active ASID */
 	ttbr1 = read_sysreg(ttbr1_el1);
+	ttbr1 &= ~TTBR_ASID_MASK;		/* safety measure */
 	ttbr1 |= ttbr0 & TTBR_ASID_MASK;
 	write_sysreg(ttbr1, ttbr1_el1);
 	isb();
@@ -453,11 +456,11 @@ extern __must_check long strnlen_user(const char __user *str, long n);
 #ifdef CONFIG_ARM64_SW_TTBR0_PAN
 	.macro	__uaccess_ttbr0_disable, tmp1
 	mrs	\tmp1, ttbr1_el1		// swapper_pg_dir
+	bic	\tmp1, \tmp1, #TTBR_ASID_MASK
 	add	\tmp1, \tmp1, #SWAPPER_DIR_SIZE	// reserved_ttbr0 at the end of swapper_pg_dir
 	msr	ttbr0_el1, \tmp1		// set reserved TTBR0_EL1
 	isb
 	sub	\tmp1, \tmp1, #SWAPPER_DIR_SIZE
-	bic	\tmp1, \tmp1, #TTBR_ASID_MASK
 	msr	ttbr1_el1, \tmp1		// set reserved ASID
 	isb
 	.endm
@@ -474,9 +477,11 @@ extern __must_check long strnlen_user(const char __user *str, long n);
 	isb
 	.endm
 
-	.macro	uaccess_ttbr0_disable, tmp1
+	.macro	uaccess_ttbr0_disable, tmp1, tmp2
 alternative_if_not ARM64_HAS_PAN
+	save_and_disable_irq \tmp2		// avoid preemption
 	__uaccess_ttbr0_disable \tmp1
+	restore_irq \tmp2
 alternative_else_nop_endif
 	.endm
 
@@ -488,7 +493,7 @@ alternative_if_not ARM64_HAS_PAN
 alternative_else_nop_endif
 	.endm
 #else
-	.macro	uaccess_ttbr0_disable, tmp1
+	.macro	uaccess_ttbr0_disable, tmp1, tmp2
 	.endm
 
 	.macro	uaccess_ttbr0_enable, tmp1, tmp2, tmp3
@@ -498,8 +503,8 @@ alternative_else_nop_endif
 /*
  * These macros are no-ops when UAO is present.
  */
-	.macro	uaccess_disable_not_uao, tmp1
-	uaccess_ttbr0_disable \tmp1
+	.macro	uaccess_disable_not_uao, tmp1, tmp2
+	uaccess_ttbr0_disable \tmp1, \tmp2
 alternative_if ARM64_ALT_PAN_NOT_UAO
 	SET_PSTATE_PAN(1)
 alternative_else_nop_endif