1 files changed, 338 insertions, 265 deletions

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index cf402be5c573..23d281ed7621 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -9,7 +9,6 @@
 #include <linux/bug.h>
 #include <linux/context_tracking.h>
 #include <linux/signal.h>
-#include <linux/personality.h>
 #include <linux/kallsyms.h>
 #include <linux/kprobes.h>
 #include <linux/spinlock.h>
@@ -27,6 +26,7 @@
 #include <linux/syscalls.h>
 #include <linux/mm_types.h>
 #include <linux/kasan.h>
+#include <linux/cfi.h>
 
 #include <asm/atomic.h>
 #include <asm/bug.h>
@@ -34,30 +34,118 @@
 #include <asm/daifflags.h>
 #include <asm/debug-monitors.h>
 #include <asm/esr.h>
+#include <asm/exception.h>
+#include <asm/extable.h>
 #include <asm/insn.h>
 #include <asm/kprobes.h>
+#include <asm/patching.h>
 #include <asm/traps.h>
 #include <asm/smp.h>
 #include <asm/stack_pointer.h>
 #include <asm/stacktrace.h>
-#include <asm/exception.h>
 #include <asm/system_misc.h>
 #include <asm/sysreg.h>
 
-static const char *handler[]= {
-	"Synchronous Abort",
-	"IRQ",
-	"FIQ",
-	"Error"
-};
+static bool __kprobes __check_eq(unsigned long pstate)
+{
+	return (pstate & PSR_Z_BIT) != 0;
+}
 
-int show_unhandled_signals = 0;
+static bool __kprobes __check_ne(unsigned long pstate)
+{
+	return (pstate & PSR_Z_BIT) == 0;
+}
+
+static bool __kprobes __check_cs(unsigned long pstate)
+{
+	return (pstate & PSR_C_BIT) != 0;
+}
+
+static bool __kprobes __check_cc(unsigned long pstate)
+{
+	return (pstate & PSR_C_BIT) == 0;
+}
+
+static bool __kprobes __check_mi(unsigned long pstate)
+{
+	return (pstate & PSR_N_BIT) != 0;
+}
+
+static bool __kprobes __check_pl(unsigned long pstate)
+{
+	return (pstate & PSR_N_BIT) == 0;
+}
+
+static bool __kprobes __check_vs(unsigned long pstate)
+{
+	return (pstate & PSR_V_BIT) != 0;
+}
+
+static bool __kprobes __check_vc(unsigned long pstate)
+{
+	return (pstate & PSR_V_BIT) == 0;
+}
+
+static bool __kprobes __check_hi(unsigned long pstate)
+{
+	pstate &= ~(pstate >> 1);	/* PSR_C_BIT &= ~PSR_Z_BIT */
+	return (pstate & PSR_C_BIT) != 0;
+}
+
+static bool __kprobes __check_ls(unsigned long pstate)
+{
+	pstate &= ~(pstate >> 1);	/* PSR_C_BIT &= ~PSR_Z_BIT */
+	return (pstate & PSR_C_BIT) == 0;
+}
+
+static bool __kprobes __check_ge(unsigned long pstate)
+{
+	pstate ^= (pstate << 3);	/* PSR_N_BIT ^= PSR_V_BIT */
+	return (pstate & PSR_N_BIT) == 0;
+}
 
-static void dump_backtrace_entry(unsigned long where)
+static bool __kprobes __check_lt(unsigned long pstate)
 {
-	printk(" %pS\n", (void *)where);
+	pstate ^= (pstate << 3);	/* PSR_N_BIT ^= PSR_V_BIT */
+	return (pstate & PSR_N_BIT) != 0;
 }
 
+static bool __kprobes __check_gt(unsigned long pstate)
+{
+	/*PSR_N_BIT ^= PSR_V_BIT */
+	unsigned long temp = pstate ^ (pstate << 3);
+
+	temp |= (pstate << 1);	/*PSR_N_BIT |= PSR_Z_BIT */
+	return (temp & PSR_N_BIT) == 0;
+}
+
+static bool __kprobes __check_le(unsigned long pstate)
+{
+	/*PSR_N_BIT ^= PSR_V_BIT */
+	unsigned long temp = pstate ^ (pstate << 3);
+
+	temp |= (pstate << 1);	/*PSR_N_BIT |= PSR_Z_BIT */
+	return (temp & PSR_N_BIT) != 0;
+}
+
+static bool __kprobes __check_al(unsigned long pstate)
+{
+	return true;
+}
+
+/*
+ * Note that the ARMv8 ARM calls condition code 0b1111 "nv", but states that
+ * it behaves identically to 0b1110 ("al").
+ */
+pstate_check_t * const aarch32_opcode_cond_checks[16] = {
+	__check_eq, __check_ne, __check_cs, __check_cc,
+	__check_mi, __check_pl, __check_vs, __check_vc,
+	__check_hi, __check_ls, __check_ge, __check_lt,
+	__check_gt, __check_le, __check_al, __check_al
+};
+
+int show_unhandled_signals = 0;
+
 static void dump_kernel_instr(const char *lvl, struct pt_regs *regs)
 {
 	unsigned long addr = instruction_pointer(regs);
@@ -83,65 +171,6 @@ static void dump_kernel_instr(const char *lvl, struct pt_regs *regs)
 	printk("%sCode: %s\n", lvl, str);
 }
 
-void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
-{
-	struct stackframe frame;
-	int skip = 0;
-
-	pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);
-
-	if (regs) {
-		if (user_mode(regs))
-			return;
-		skip = 1;
-	}
-
-	if (!tsk)
-		tsk = current;
-
-	if (!try_get_task_stack(tsk))
-		return;
-
-	if (tsk == current) {
-		start_backtrace(&frame,
-				(unsigned long)__builtin_frame_address(0),
-				(unsigned long)dump_backtrace);
-	} else {
-		/*
-		 * task blocked in __switch_to
-		 */
-		start_backtrace(&frame,
-				thread_saved_fp(tsk),
-				thread_saved_pc(tsk));
-	}
-
-	printk("Call trace:\n");
-	do {
-		/* skip until specified stack frame */
-		if (!skip) {
-			dump_backtrace_entry(frame.pc);
-		} else if (frame.fp == regs->regs[29]) {
-			skip = 0;
-			/*
-			 * Mostly, this is the case where this function is
-			 * called in panic/abort. As exception handler's
-			 * stack frame does not contain the corresponding pc
-			 * at which an exception has taken place, use regs->pc
-			 * instead.
-			 */
-			dump_backtrace_entry(regs->pc);
-		}
-	} while (!unwind_frame(tsk, &frame));
-
-	put_task_stack(tsk);
-}
-
-void show_stack(struct task_struct *tsk, unsigned long *sp)
-{
-	dump_backtrace(NULL, tsk);
-	barrier();
-}
-
 #ifdef CONFIG_PREEMPT
 #define S_PREEMPT " PREEMPT"
 #elif defined(CONFIG_PREEMPT_RT)
@@ -152,12 +181,12 @@ void show_stack(struct task_struct *tsk, unsigned long *sp)
 
 #define S_SMP " SMP"
 
-static int __die(const char *str, int err, struct pt_regs *regs)
+static int __die(const char *str, long err, struct pt_regs *regs)
 {
 	static int die_counter;
 	int ret;
 
-	pr_emerg("Internal error: %s: %x [#%d]" S_PREEMPT S_SMP "\n",
+	pr_emerg("Internal error: %s: %016lx [#%d]" S_PREEMPT S_SMP "\n",
 		 str, err, ++die_counter);
 
 	/* trap and error numbers are mostly meaningless on ARM */
@@ -178,7 +207,7 @@ static DEFINE_RAW_SPINLOCK(die_lock);
 /*
  * This function is protected against re-entrancy.
  */
-void die(const char *str, struct pt_regs *regs, int err)
+void die(const char *str, struct pt_regs *regs, long err)
 {
 	int ret;
 	unsigned long flags;
@@ -199,14 +228,14 @@ void die(const char *str, struct pt_regs *regs, int err)
 	oops_exit();
 
 	if (in_interrupt())
-		panic("Fatal exception in interrupt");
+		panic("%s: Fatal exception in interrupt", str);
 	if (panic_on_oops)
-		panic("Fatal exception");
+		panic("%s: Fatal exception", str);
 
 	raw_spin_unlock_irqrestore(&die_lock, flags);
 
 	if (ret != NOTIFY_STOP)
-		do_exit(SIGSEGV);
+		make_task_dead(SIGSEGV);
 }
 
 static void arm64_show_signal(int signo, const char *str)
@@ -214,7 +243,7 @@ static void arm64_show_signal(int signo, const char *str)
 	static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL,
 				      DEFAULT_RATELIMIT_BURST);
 	struct task_struct *tsk = current;
-	unsigned int esr = tsk->thread.fault_code;
+	unsigned long esr = tsk->thread.fault_code;
 	struct pt_regs *regs = task_pt_regs(tsk);
 
 	/* Leave if the signal won't be shown */
@@ -225,7 +254,7 @@ static void arm64_show_signal(int signo, const char *str)
 
 	pr_info("%s[%d]: unhandled exception: ", tsk->comm, task_pid_nr(tsk));
 	if (esr)
-		pr_cont("%s, ESR 0x%08x, ", esr_get_class_string(esr), esr);
+		pr_cont("%s, ESR 0x%016lx, ", esr_get_class_string(esr), esr);
 
 	pr_cont("%s", str);
 	print_vma_addr(KERN_CONT " in ", regs->pc);
@@ -233,45 +262,100 @@ static void arm64_show_signal(int signo, const char *str)
 	__show_regs(regs);
 }
 
-void arm64_force_sig_fault(int signo, int code, void __user *addr,
+void arm64_force_sig_fault(int signo, int code, unsigned long far,
 			   const char *str)
 {
 	arm64_show_signal(signo, str);
 	if (signo == SIGKILL)
 		force_sig(SIGKILL);
 	else
-		force_sig_fault(signo, code, addr);
+		force_sig_fault(signo, code, (void __user *)far);
 }
 
-void arm64_force_sig_mceerr(int code, void __user *addr, short lsb,
+void arm64_force_sig_mceerr(int code, unsigned long far, short lsb,
 			    const char *str)
 {
 	arm64_show_signal(SIGBUS, str);
-	force_sig_mceerr(code, addr, lsb);
+	force_sig_mceerr(code, (void __user *)far, lsb);
 }
 
-void arm64_force_sig_ptrace_errno_trap(int errno, void __user *addr,
+void arm64_force_sig_ptrace_errno_trap(int errno, unsigned long far,
 				       const char *str)
 {
 	arm64_show_signal(SIGTRAP, str);
-	force_sig_ptrace_errno_trap(errno, addr);
+	force_sig_ptrace_errno_trap(errno, (void __user *)far);
 }
 
 void arm64_notify_die(const char *str, struct pt_regs *regs,
-		      int signo, int sicode, void __user *addr,
-		      int err)
+		      int signo, int sicode, unsigned long far,
+		      unsigned long err)
 {
 	if (user_mode(regs)) {
 		WARN_ON(regs != current_pt_regs());
 		current->thread.fault_address = 0;
 		current->thread.fault_code = err;
 
-		arm64_force_sig_fault(signo, sicode, addr, str);
+		arm64_force_sig_fault(signo, sicode, far, str);
 	} else {
 		die(str, regs, err);
 	}
 }
 
+#ifdef CONFIG_COMPAT
+#define PSTATE_IT_1_0_SHIFT	25
+#define PSTATE_IT_1_0_MASK	(0x3 << PSTATE_IT_1_0_SHIFT)
+#define PSTATE_IT_7_2_SHIFT	10
+#define PSTATE_IT_7_2_MASK	(0x3f << PSTATE_IT_7_2_SHIFT)
+
+static u32 compat_get_it_state(struct pt_regs *regs)
+{
+	u32 it, pstate = regs->pstate;
+
+	it  = (pstate & PSTATE_IT_1_0_MASK) >> PSTATE_IT_1_0_SHIFT;
+	it |= ((pstate & PSTATE_IT_7_2_MASK) >> PSTATE_IT_7_2_SHIFT) << 2;
+
+	return it;
+}
+
+static void compat_set_it_state(struct pt_regs *regs, u32 it)
+{
+	u32 pstate_it;
+
+	pstate_it  = (it << PSTATE_IT_1_0_SHIFT) & PSTATE_IT_1_0_MASK;
+	pstate_it |= ((it >> 2) << PSTATE_IT_7_2_SHIFT) & PSTATE_IT_7_2_MASK;
+
+	regs->pstate &= ~PSR_AA32_IT_MASK;
+	regs->pstate |= pstate_it;
+}
+
+static void advance_itstate(struct pt_regs *regs)
+{
+	u32 it;
+
+	/* ARM mode */
+	if (!(regs->pstate & PSR_AA32_T_BIT) ||
+	    !(regs->pstate & PSR_AA32_IT_MASK))
+		return;
+
+	it  = compat_get_it_state(regs);
+
+	/*
+	 * If this is the last instruction of the block, wipe the IT
+	 * state. Otherwise advance it.
+	 */
+	if (!(it & 7))
+		it = 0;
+	else
+		it = (it & 0xe0) | ((it << 1) & 0x1f);
+
+	compat_set_it_state(regs, it);
+}
+#else
+static void advance_itstate(struct pt_regs *regs)
+{
+}
+#endif
+
 void arm64_skip_faulting_instruction(struct pt_regs *regs, unsigned long size)
 {
 	regs->pc += size;
@@ -282,6 +366,11 @@ void arm64_skip_faulting_instruction(struct pt_regs *regs, unsigned long size)
 	 */
 	if (user_mode(regs))
 		user_fastforward_single_step(current);
+
+	if (compat_user_mode(regs))
+		advance_itstate(regs);
+	else
+		regs->pstate &= ~PSR_BTYPE_MASK;
 }
 
 static LIST_HEAD(undef_hook);
@@ -311,11 +400,11 @@ static int call_undef_hook(struct pt_regs *regs)
 	unsigned long flags;
 	u32 instr;
 	int (*fn)(struct pt_regs *regs, u32 instr) = NULL;
-	void __user *pc = (void __user *)instruction_pointer(regs);
+	unsigned long pc = instruction_pointer(regs);
 
 	if (!user_mode(regs)) {
 		__le32 instr_le;
-		if (probe_kernel_address((__force __le32 *)pc, instr_le))
+		if (get_kernel_nofault(instr_le, (__le32 *)pc))
 			goto exit;
 		instr = le32_to_cpu(instr_le);
 	} else if (compat_thumb_mode(regs)) {
@@ -351,7 +440,7 @@ exit:
 	return fn ? fn(regs, instr) : 1;
 }
 
-void force_signal_inject(int signal, int code, unsigned long address)
+void force_signal_inject(int signal, int code, unsigned long address, unsigned long err)
 {
 	const char *desc;
 	struct pt_regs *regs = current_pt_regs();
@@ -377,7 +466,7 @@ void force_signal_inject(int signal, int code, unsigned long address)
 		signal = SIGKILL;
 	}
 
-	arm64_notify_die(desc, regs, signal, code, (void __user *)address, 0);
+	arm64_notify_die(desc, regs, signal, code, address, err);
 }
 
 /*
@@ -387,17 +476,17 @@ void arm64_notify_segfault(unsigned long addr)
 {
 	int code;
 
-	down_read(&current->mm->mmap_sem);
-	if (find_vma(current->mm, addr) == NULL)
+	mmap_read_lock(current->mm);
+	if (find_vma(current->mm, untagged_addr(addr)) == NULL)
 		code = SEGV_MAPERR;
 	else
 		code = SEGV_ACCERR;
-	up_read(&current->mm->mmap_sem);
+	mmap_read_unlock(current->mm);
 
-	force_signal_inject(SIGSEGV, code, addr);
+	force_signal_inject(SIGSEGV, code, addr, 0);
 }
 
-void do_undefinstr(struct pt_regs *regs)
+void do_undefinstr(struct pt_regs *regs, unsigned long esr)
 {
 	/* check for AArch32 breakpoint instructions */
 	if (!aarch32_break_handler(regs))
@@ -406,13 +495,41 @@ void do_undefinstr(struct pt_regs *regs)
 	if (call_undef_hook(regs) == 0)
 		return;
 
-	BUG_ON(!user_mode(regs));
-	force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc);
+	if (!user_mode(regs))
+		die("Oops - Undefined instruction", regs, esr);
+
+	force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0);
 }
 NOKPROBE_SYMBOL(do_undefinstr);
 
+void do_el0_bti(struct pt_regs *regs)
+{
+	force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0);
+}
+
+void do_el1_bti(struct pt_regs *regs, unsigned long esr)
+{
+	die("Oops - BTI", regs, esr);
+}
+NOKPROBE_SYMBOL(do_el1_bti);
+
+void do_el0_fpac(struct pt_regs *regs, unsigned long esr)
+{
+	force_signal_inject(SIGILL, ILL_ILLOPN, regs->pc, esr);
+}
+
+void do_el1_fpac(struct pt_regs *regs, unsigned long esr)
+{
+	/*
+	 * Unexpected FPAC exception in the kernel: kill the task before it
+	 * does any more harm.
+	 */
+	die("Oops - FPAC", regs, esr);
+}
+NOKPROBE_SYMBOL(do_el1_fpac)
+
 #define __user_cache_maint(insn, address, res)			\
-	if (address >= user_addr_max()) {			\
+	if (address >= TASK_SIZE_MAX) {				\
 		res = -EFAULT;					\
 	} else {						\
 		uaccess_ttbr0_enable();				\
@@ -420,25 +537,21 @@ NOKPROBE_SYMBOL(do_undefinstr);
 			"1:	" insn ", %1\n"			\
 			"	mov	%w0, #0\n"		\
 			"2:\n"					\
-			"	.pushsection .fixup,\"ax\"\n"	\
-			"	.align	2\n"			\
-			"3:	mov	%w0, %w2\n"		\
-			"	b	2b\n"			\
-			"	.popsection\n"			\
-			_ASM_EXTABLE(1b, 3b)			\
+			_ASM_EXTABLE_UACCESS_ERR(1b, 2b, %w0)	\
 			: "=r" (res)				\
-			: "r" (address), "i" (-EFAULT));	\
+			: "r" (address));			\
 		uaccess_ttbr0_disable();			\
 	}
 
-static void user_cache_maint_handler(unsigned int esr, struct pt_regs *regs)
+static void user_cache_maint_handler(unsigned long esr, struct pt_regs *regs)
 {
-	unsigned long address;
+	unsigned long tagged_address, address;
 	int rt = ESR_ELx_SYS64_ISS_RT(esr);
 	int crm = (esr & ESR_ELx_SYS64_ISS_CRM_MASK) >> ESR_ELx_SYS64_ISS_CRM_SHIFT;
 	int ret = 0;
 
-	address = untagged_addr(pt_regs_read_reg(regs, rt));
+	tagged_address = pt_regs_read_reg(regs, rt);
+	address = untagged_addr(tagged_address);
 
 	switch (crm) {
 	case ESR_ELx_SYS64_ISS_CRM_DC_CVAU:	/* DC CVAU, gets promoted */
@@ -460,28 +573,28 @@ static void user_cache_maint_handler(unsigned int esr, struct pt_regs *regs)
 		__user_cache_maint("ic ivau", address, ret);
 		break;
 	default:
-		force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc);
+		force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0);
 		return;
 	}
 
 	if (ret)
-		arm64_notify_segfault(address);
+		arm64_notify_segfault(tagged_address);
 	else
 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
 }
 
-static void ctr_read_handler(unsigned int esr, struct pt_regs *regs)
+static void ctr_read_handler(unsigned long esr, struct pt_regs *regs)
 {
 	int rt = ESR_ELx_SYS64_ISS_RT(esr);
 	unsigned long val = arm64_ftr_reg_user_value(&arm64_ftr_reg_ctrel0);
 
 	if (cpus_have_const_cap(ARM64_WORKAROUND_1542419)) {
 		/* Hide DIC so that we can trap the unnecessary maintenance...*/
-		val &= ~BIT(CTR_DIC_SHIFT);
+		val &= ~BIT(CTR_EL0_DIC_SHIFT);
 
 		/* ... and fake IminLine to reduce the number of traps. */
-		val &= ~CTR_IMINLINE_MASK;
-		val |= (PAGE_SHIFT - 2) & CTR_IMINLINE_MASK;
+		val &= ~CTR_EL0_IminLine_MASK;
+		val |= (PAGE_SHIFT - 2) & CTR_EL0_IminLine_MASK;
 	}
 
 	pt_regs_write_reg(regs, rt, val);
@@ -489,7 +602,7 @@ static void ctr_read_handler(unsigned int esr, struct pt_regs *regs)
 	arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
 }
 
-static void cntvct_read_handler(unsigned int esr, struct pt_regs *regs)
+static void cntvct_read_handler(unsigned long esr, struct pt_regs *regs)
 {
 	int rt = ESR_ELx_SYS64_ISS_RT(esr);
 
@@ -497,7 +610,7 @@ static void cntvct_read_handler(unsigned int esr, struct pt_regs *regs)
 	arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
 }
 
-static void cntfrq_read_handler(unsigned int esr, struct pt_regs *regs)
+static void cntfrq_read_handler(unsigned long esr, struct pt_regs *regs)
 {
 	int rt = ESR_ELx_SYS64_ISS_RT(esr);
 
@@ -505,7 +618,7 @@ static void cntfrq_read_handler(unsigned int esr, struct pt_regs *regs)
 	arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
 }
 
-static void mrs_handler(unsigned int esr, struct pt_regs *regs)
+static void mrs_handler(unsigned long esr, struct pt_regs *regs)
 {
 	u32 sysreg, rt;
 
@@ -513,18 +626,18 @@ static void mrs_handler(unsigned int esr, struct pt_regs *regs)
 	sysreg = esr_sys64_to_sysreg(esr);
 
 	if (do_emulate_mrs(regs, sysreg, rt) != 0)
-		force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc);
+		force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0);
 }
 
-static void wfi_handler(unsigned int esr, struct pt_regs *regs)
+static void wfi_handler(unsigned long esr, struct pt_regs *regs)
 {
 	arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
 }
 
 struct sys64_hook {
-	unsigned int esr_mask;
-	unsigned int esr_val;
-	void (*handler)(unsigned int esr, struct pt_regs *regs);
+	unsigned long esr_mask;
+	unsigned long esr_val;
+	void (*handler)(unsigned long esr, struct pt_regs *regs);
 };
 
 static const struct sys64_hook sys64_hooks[] = {
@@ -546,6 +659,12 @@ static const struct sys64_hook sys64_hooks[] = {
 		.handler = cntvct_read_handler,
 	},
 	{
+		/* Trap read access to CNTVCTSS_EL0 */
+		.esr_mask = ESR_ELx_SYS64_ISS_SYS_OP_MASK,
+		.esr_val = ESR_ELx_SYS64_ISS_SYS_CNTVCTSS,
+		.handler = cntvct_read_handler,
+	},
+	{
 		/* Trap read access to CNTFRQ_EL0 */
 		.esr_mask = ESR_ELx_SYS64_ISS_SYS_OP_MASK,
 		.esr_val = ESR_ELx_SYS64_ISS_SYS_CNTFRQ,
@@ -566,35 +685,8 @@ static const struct sys64_hook sys64_hooks[] = {
 	{},
 };
 
-
 #ifdef CONFIG_COMPAT
-#define PSTATE_IT_1_0_SHIFT	25
-#define PSTATE_IT_1_0_MASK	(0x3 << PSTATE_IT_1_0_SHIFT)
-#define PSTATE_IT_7_2_SHIFT	10
-#define PSTATE_IT_7_2_MASK	(0x3f << PSTATE_IT_7_2_SHIFT)
-
-static u32 compat_get_it_state(struct pt_regs *regs)
-{
-	u32 it, pstate = regs->pstate;
-
-	it  = (pstate & PSTATE_IT_1_0_MASK) >> PSTATE_IT_1_0_SHIFT;
-	it |= ((pstate & PSTATE_IT_7_2_MASK) >> PSTATE_IT_7_2_SHIFT) << 2;
-
-	return it;
-}
-
-static void compat_set_it_state(struct pt_regs *regs, u32 it)
-{
-	u32 pstate_it;
-
-	pstate_it  = (it << PSTATE_IT_1_0_SHIFT) & PSTATE_IT_1_0_MASK;
-	pstate_it |= ((it >> 2) << PSTATE_IT_7_2_SHIFT) & PSTATE_IT_7_2_MASK;
-
-	regs->pstate &= ~PSR_AA32_IT_MASK;
-	regs->pstate |= pstate_it;
-}
-
-static bool cp15_cond_valid(unsigned int esr, struct pt_regs *regs)
+static bool cp15_cond_valid(unsigned long esr, struct pt_regs *regs)
 {
 	int cond;
 
@@ -614,42 +706,12 @@ static bool cp15_cond_valid(unsigned int esr, struct pt_regs *regs)
 	return aarch32_opcode_cond_checks[cond](regs->pstate);
 }
 
-static void advance_itstate(struct pt_regs *regs)
-{
-	u32 it;
-
-	/* ARM mode */
-	if (!(regs->pstate & PSR_AA32_T_BIT) ||
-	    !(regs->pstate & PSR_AA32_IT_MASK))
-		return;
-
-	it  = compat_get_it_state(regs);
-
-	/*
-	 * If this is the last instruction of the block, wipe the IT
-	 * state. Otherwise advance it.
-	 */
-	if (!(it & 7))
-		it = 0;
-	else
-		it = (it & 0xe0) | ((it << 1) & 0x1f);
-
-	compat_set_it_state(regs, it);
-}
-
-static void arm64_compat_skip_faulting_instruction(struct pt_regs *regs,
-						   unsigned int sz)
-{
-	advance_itstate(regs);
-	arm64_skip_faulting_instruction(regs, sz);
-}
-
-static void compat_cntfrq_read_handler(unsigned int esr, struct pt_regs *regs)
+static void compat_cntfrq_read_handler(unsigned long esr, struct pt_regs *regs)
 {
 	int reg = (esr & ESR_ELx_CP15_32_ISS_RT_MASK) >> ESR_ELx_CP15_32_ISS_RT_SHIFT;
 
 	pt_regs_write_reg(regs, reg, arch_timer_get_rate());
-	arm64_compat_skip_faulting_instruction(regs, 4);
+	arm64_skip_faulting_instruction(regs, 4);
 }
 
 static const struct sys64_hook cp15_32_hooks[] = {
@@ -661,7 +723,7 @@ static const struct sys64_hook cp15_32_hooks[] = {
 	{},
 };
 
-static void compat_cntvct_read_handler(unsigned int esr, struct pt_regs *regs)
+static void compat_cntvct_read_handler(unsigned long esr, struct pt_regs *regs)
 {
 	int rt = (esr & ESR_ELx_CP15_64_ISS_RT_MASK) >> ESR_ELx_CP15_64_ISS_RT_SHIFT;
 	int rt2 = (esr & ESR_ELx_CP15_64_ISS_RT2_MASK) >> ESR_ELx_CP15_64_ISS_RT2_SHIFT;
@@ -669,7 +731,7 @@ static void compat_cntvct_read_handler(unsigned int esr, struct pt_regs *regs)
 
 	pt_regs_write_reg(regs, rt, lower_32_bits(val));
 	pt_regs_write_reg(regs, rt2, upper_32_bits(val));
-	arm64_compat_skip_faulting_instruction(regs, 4);
+	arm64_skip_faulting_instruction(regs, 4);
 }
 
 static const struct sys64_hook cp15_64_hooks[] = {
@@ -678,10 +740,15 @@ static const struct sys64_hook cp15_64_hooks[] = {
 		.esr_val = ESR_ELx_CP15_64_ISS_SYS_CNTVCT,
 		.handler = compat_cntvct_read_handler,
 	},
+	{
+		.esr_mask = ESR_ELx_CP15_64_ISS_SYS_MASK,
+		.esr_val = ESR_ELx_CP15_64_ISS_SYS_CNTVCTSS,
+		.handler = compat_cntvct_read_handler,
+	},
 	{},
 };
 
-void do_cp15instr(unsigned int esr, struct pt_regs *regs)
+void do_cp15instr(unsigned long esr, struct pt_regs *regs)
 {
 	const struct sys64_hook *hook, *hook_base;
 
@@ -690,7 +757,7 @@ void do_cp15instr(unsigned int esr, struct pt_regs *regs)
 		 * There is no T16 variant of a CP access, so we
 		 * always advance PC by 4 bytes.
 		 */
-		arm64_compat_skip_faulting_instruction(regs, 4);
+		arm64_skip_faulting_instruction(regs, 4);
 		return;
 	}
 
@@ -702,7 +769,7 @@ void do_cp15instr(unsigned int esr, struct pt_regs *regs)
 		hook_base = cp15_64_hooks;
 		break;
 	default:
-		do_undefinstr(regs);
+		do_undefinstr(regs, esr);
 		return;
 	}
 
@@ -717,12 +784,12 @@ void do_cp15instr(unsigned int esr, struct pt_regs *regs)
 	 * EL0. Fall back to our usual undefined instruction handler
 	 * so that we handle these consistently.
 	 */
-	do_undefinstr(regs);
+	do_undefinstr(regs, esr);
 }
 NOKPROBE_SYMBOL(do_cp15instr);
 #endif
 
-void do_sysinstr(unsigned int esr, struct pt_regs *regs)
+void do_sysinstr(unsigned long esr, struct pt_regs *regs)
 {
 	const struct sys64_hook *hook;
 
@@ -737,7 +804,7 @@ void do_sysinstr(unsigned int esr, struct pt_regs *regs)
 	 * back to our usual undefined instruction handler so that we handle
 	 * these consistently.
 	 */
-	do_undefinstr(regs);
+	do_undefinstr(regs, esr);
 }
 NOKPROBE_SYMBOL(do_sysinstr);
 
@@ -753,6 +820,7 @@ static const char *esr_class_str[] = {
 	[ESR_ELx_EC_CP10_ID]		= "CP10 MRC/VMRS",
 	[ESR_ELx_EC_PAC]		= "PAC",
 	[ESR_ELx_EC_CP14_64]		= "CP14 MCRR/MRRC",
+	[ESR_ELx_EC_BTI]		= "BTI",
 	[ESR_ELx_EC_ILL]		= "PSTATE.IL",
 	[ESR_ELx_EC_SVC32]		= "SVC (AArch32)",
 	[ESR_ELx_EC_HVC32]		= "HVC (AArch32)",
@@ -763,6 +831,8 @@ static const char *esr_class_str[] = {
 	[ESR_ELx_EC_SYS64]		= "MSR/MRS (AArch64)",
 	[ESR_ELx_EC_SVE]		= "SVE",
 	[ESR_ELx_EC_ERET]		= "ERET/ERETAA/ERETAB",
+	[ESR_ELx_EC_FPAC]		= "FPAC",
+	[ESR_ELx_EC_SME]		= "SME",
 	[ESR_ELx_EC_IMP_DEF]		= "EL3 IMP DEF",
 	[ESR_ELx_EC_IABT_LOW]		= "IABT (lower EL)",
 	[ESR_ELx_EC_IABT_CUR]		= "IABT (current EL)",
@@ -784,34 +854,18 @@ static const char *esr_class_str[] = {
 	[ESR_ELx_EC_BRK64]		= "BRK (AArch64)",
 };
 
-const char *esr_get_class_string(u32 esr)
+const char *esr_get_class_string(unsigned long esr)
 {
 	return esr_class_str[ESR_ELx_EC(esr)];
 }
 
 /*
- * bad_mode handles the impossible case in the exception vector. This is always
- * fatal.
- */
-asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr)
-{
-	console_verbose();
-
-	pr_crit("Bad mode in %s handler detected on CPU%d, code 0x%08x -- %s\n",
-		handler[reason], smp_processor_id(), esr,
-		esr_get_class_string(esr));
-
-	local_daif_mask();
-	panic("bad mode");
-}
-
-/*
  * bad_el0_sync handles unexpected, but potentially recoverable synchronous
- * exceptions taken from EL0. Unlike bad_mode, this returns.
+ * exceptions taken from EL0.
  */
-void bad_el0_sync(struct pt_regs *regs, int reason, unsigned int esr)
+void bad_el0_sync(struct pt_regs *regs, int reason, unsigned long esr)
 {
-	void __user *pc = (void __user *)instruction_pointer(regs);
+	unsigned long pc = instruction_pointer(regs);
 
 	current->thread.fault_address = 0;
 	current->thread.fault_code = esr;
@@ -825,24 +879,22 @@ void bad_el0_sync(struct pt_regs *regs, int reason, unsigned int esr)
 DEFINE_PER_CPU(unsigned long [OVERFLOW_STACK_SIZE/sizeof(long)], overflow_stack)
 	__aligned(16);
 
-asmlinkage void handle_bad_stack(struct pt_regs *regs)
+void panic_bad_stack(struct pt_regs *regs, unsigned long esr, unsigned long far)
 {
 	unsigned long tsk_stk = (unsigned long)current->stack;
 	unsigned long irq_stk = (unsigned long)this_cpu_read(irq_stack_ptr);
 	unsigned long ovf_stk = (unsigned long)this_cpu_ptr(overflow_stack);
-	unsigned int esr = read_sysreg(esr_el1);
-	unsigned long far = read_sysreg(far_el1);
 
 	console_verbose();
 	pr_emerg("Insufficient stack space to handle exception!");
 
-	pr_emerg("ESR: 0x%08x -- %s\n", esr, esr_get_class_string(esr));
+	pr_emerg("ESR: 0x%016lx -- %s\n", esr, esr_get_class_string(esr));
 	pr_emerg("FAR: 0x%016lx\n", far);
 
 	pr_emerg("Task stack:     [0x%016lx..0x%016lx]\n",
 		 tsk_stk, tsk_stk + THREAD_SIZE);
 	pr_emerg("IRQ stack:      [0x%016lx..0x%016lx]\n",
-		 irq_stk, irq_stk + THREAD_SIZE);
+		 irq_stk, irq_stk + IRQ_STACK_SIZE);
 	pr_emerg("Overflow stack: [0x%016lx..0x%016lx]\n",
 		 ovf_stk, ovf_stk + OVERFLOW_STACK_SIZE);
 
@@ -857,11 +909,11 @@ asmlinkage void handle_bad_stack(struct pt_regs *regs)
 }
 #endif
 
-void __noreturn arm64_serror_panic(struct pt_regs *regs, u32 esr)
+void __noreturn arm64_serror_panic(struct pt_regs *regs, unsigned long esr)
 {
 	console_verbose();
 
-	pr_crit("SError Interrupt on CPU%d, code 0x%08x -- %s\n",
+	pr_crit("SError Interrupt on CPU%d, code 0x%016lx -- %s\n",
 		smp_processor_id(), esr, esr_get_class_string(esr));
 	if (regs)
 		__show_regs(regs);
@@ -872,9 +924,9 @@ void __noreturn arm64_serror_panic(struct pt_regs *regs, u32 esr)
 	unreachable();
 }
 
-bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr)
+bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned long esr)
 {
-	u32 aet = arm64_ras_serror_get_severity(esr);
+	unsigned long aet = arm64_ras_serror_get_severity(esr);
 
 	switch (aet) {
 	case ESR_ELx_AET_CE:	/* corrected error */
@@ -904,46 +956,11 @@ bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr)
 	}
 }
 
-asmlinkage void do_serror(struct pt_regs *regs, unsigned int esr)
+void do_serror(struct pt_regs *regs, unsigned long esr)
 {
-	const bool was_in_nmi = in_nmi();
-
-	if (!was_in_nmi)
-		nmi_enter();
-
 	/* non-RAS errors are not containable */
 	if (!arm64_is_ras_serror(esr) || arm64_is_fatal_ras_serror(regs, esr))
 		arm64_serror_panic(regs, esr);
-
-	if (!was_in_nmi)
-		nmi_exit();
-}
-
-asmlinkage void enter_from_user_mode(void)
-{
-	CT_WARN_ON(ct_state() != CONTEXT_USER);
-	user_exit_irqoff();
-}
-NOKPROBE_SYMBOL(enter_from_user_mode);
-
-void __pte_error(const char *file, int line, unsigned long val)
-{
-	pr_err("%s:%d: bad pte %016lx.\n", file, line, val);
-}
-
-void __pmd_error(const char *file, int line, unsigned long val)
-{
-	pr_err("%s:%d: bad pmd %016lx.\n", file, line, val);
-}
-
-void __pud_error(const char *file, int line, unsigned long val)
-{
-	pr_err("%s:%d: bad pud %016lx.\n", file, line, val);
-}
-
-void __pgd_error(const char *file, int line, unsigned long val)
-{
-	pr_err("%s:%d: bad pgd %016lx.\n", file, line, val);
 }
 
 /* GENERIC_BUG traps */
@@ -960,11 +977,11 @@ int is_valid_bugaddr(unsigned long addr)
 	return 1;
 }
 
-static int bug_handler(struct pt_regs *regs, unsigned int esr)
+static int bug_handler(struct pt_regs *regs, unsigned long esr)
 {
 	switch (report_bug(regs->pc, regs)) {
 	case BUG_TRAP_TYPE_BUG:
-		die("Oops - BUG", regs, 0);
+		die("Oops - BUG", regs, esr);
 		break;
 
 	case BUG_TRAP_TYPE_WARN:
@@ -985,6 +1002,53 @@ static struct break_hook bug_break_hook = {
 	.imm = BUG_BRK_IMM,
 };
 
+#ifdef CONFIG_CFI_CLANG
+static int cfi_handler(struct pt_regs *regs, unsigned long esr)
+{
+	unsigned long target;
+	u32 type;
+
+	target = pt_regs_read_reg(regs, FIELD_GET(CFI_BRK_IMM_TARGET, esr));
+	type = (u32)pt_regs_read_reg(regs, FIELD_GET(CFI_BRK_IMM_TYPE, esr));
+
+	switch (report_cfi_failure(regs, regs->pc, &target, type)) {
+	case BUG_TRAP_TYPE_BUG:
+		die("Oops - CFI", regs, 0);
+		break;
+
+	case BUG_TRAP_TYPE_WARN:
+		break;
+
+	default:
+		return DBG_HOOK_ERROR;
+	}
+
+	arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
+	return DBG_HOOK_HANDLED;
+}
+
+static struct break_hook cfi_break_hook = {
+	.fn = cfi_handler,
+	.imm = CFI_BRK_IMM_BASE,
+	.mask = CFI_BRK_IMM_MASK,
+};
+#endif /* CONFIG_CFI_CLANG */
+
+static int reserved_fault_handler(struct pt_regs *regs, unsigned long esr)
+{
+	pr_err("%s generated an invalid instruction at %pS!\n",
+		"Kernel text patching",
+		(void *)instruction_pointer(regs));
+
+	/* We cannot handle this */
+	return DBG_HOOK_ERROR;
+}
+
+static struct break_hook fault_break_hook = {
+	.fn = reserved_fault_handler,
+	.imm = FAULT_BRK_IMM,
+};
+
 #ifdef CONFIG_KASAN_SW_TAGS
 
 #define KASAN_ESR_RECOVER	0x20
@@ -992,7 +1056,7 @@ static struct break_hook bug_break_hook = {
 #define KASAN_ESR_SIZE_MASK	0x0f
 #define KASAN_ESR_SIZE(esr)	(1 << ((esr) & KASAN_ESR_SIZE_MASK))
 
-static int kasan_handler(struct pt_regs *regs, unsigned int esr)
+static int kasan_handler(struct pt_regs *regs, unsigned long esr)
 {
 	bool recover = esr & KASAN_ESR_RECOVER;
 	bool write = esr & KASAN_ESR_WRITE;
@@ -1017,7 +1081,7 @@ static int kasan_handler(struct pt_regs *regs, unsigned int esr)
 	 * This is something that might be fixed at some point in the future.
 	 */
 	if (!recover)
-		die("Oops - KASAN", regs, 0);
+		die("Oops - KASAN", regs, esr);
 
 	/* If thread survives, skip over the brk instruction and continue: */
 	arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
@@ -1031,27 +1095,36 @@ static struct break_hook kasan_break_hook = {
 };
 #endif
 
+
+#define esr_comment(esr) ((esr) & ESR_ELx_BRK64_ISS_COMMENT_MASK)
+
 /*
  * Initial handler for AArch64 BRK exceptions
  * This handler only used until debug_traps_init().
  */
-int __init early_brk64(unsigned long addr, unsigned int esr,
+int __init early_brk64(unsigned long addr, unsigned long esr,
 		struct pt_regs *regs)
 {
+#ifdef CONFIG_CFI_CLANG
+	if ((esr_comment(esr) & ~CFI_BRK_IMM_MASK) == CFI_BRK_IMM_BASE)
+		return cfi_handler(regs, esr) != DBG_HOOK_HANDLED;
+#endif
 #ifdef CONFIG_KASAN_SW_TAGS
-	unsigned int comment = esr & ESR_ELx_BRK64_ISS_COMMENT_MASK;
-
-	if ((comment & ~KASAN_BRK_MASK) == KASAN_BRK_IMM)
+	if ((esr_comment(esr) & ~KASAN_BRK_MASK) == KASAN_BRK_IMM)
 		return kasan_handler(regs, esr) != DBG_HOOK_HANDLED;
 #endif
 	return bug_handler(regs, esr) != DBG_HOOK_HANDLED;
 }
 
-/* This registration must happen early, before debug_traps_init(). */
 void __init trap_init(void)
 {
 	register_kernel_break_hook(&bug_break_hook);
+#ifdef CONFIG_CFI_CLANG
+	register_kernel_break_hook(&cfi_break_hook);
+#endif
+	register_kernel_break_hook(&fault_break_hook);
 #ifdef CONFIG_KASAN_SW_TAGS
 	register_kernel_break_hook(&kasan_break_hook);
 #endif
+	debug_traps_init();
 }