diff --git a/Documentation/arm64/tagged-pointers.rst b/Documentation/arm64/tagged-pointers.rst
index eab4323609b9..032c09a876f4 100644
--- a/Documentation/arm64/tagged-pointers.rst
+++ b/Documentation/arm64/tagged-pointers.rst
@@ -53,12 +53,21 @@ visibility.
 Preserving tags
 ---------------
 
-Non-zero tags are not preserved when delivering signals. This means that
-signal handlers in applications making use of tags cannot rely on the
-tag information for user virtual addresses being maintained for fields
-inside siginfo_t. One exception to this rule is for signals raised in
-response to watchpoint debug exceptions, where the tag information will
-be preserved.
+Non-zero tags are not preserved in the fault address fields
+siginfo.si_addr or sigcontext.fault_address when delivering
+signals. This means that signal handlers in applications making use
+of tags cannot rely on the tag information for user virtual addresses
+being maintained in these fields. One exception to this rule is for
+signals raised in response to watchpoint debug exceptions, where the
+tag information will be preserved.
+
+The fault address tag is preserved in the si_addr_tag_bits field
+of siginfo, which is set for signals raised in response to data aborts
+and instruction aborts. The si_addr_tag_bits_mask field indicates
+which bits of the field are valid. The validity of these fields is
+indicated by the SIXFLAG_ADDR_TAG_BITS flag in siginfo.si_xflags,
+and the validity of si_xflags in turn is indicated by the kernel
+indicating support for the sigaction.sa_flags flag SA_XFLAGS.
 
 The architecture prevents the use of a tagged PC, so the upper byte will
 be set to a sign-extension of bit 55 on exception return.
diff --git a/arch/arm64/include/asm/exception.h b/arch/arm64/include/asm/exception.h
index 99b9383cd036..2a8aa1884d8a 100644
--- a/arch/arm64/include/asm/exception.h
+++ b/arch/arm64/include/asm/exception.h
@@ -32,7 +32,7 @@ static inline u32 disr_to_esr(u64 disr)
 }
 
 asmlinkage void enter_from_user_mode(void);
-void do_mem_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs);
+void do_mem_abort(unsigned long far, unsigned int esr, struct pt_regs *regs);
 void do_undefinstr(struct pt_regs *regs);
 void do_bti(struct pt_regs *regs);
 asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr);
diff --git a/arch/arm64/include/asm/signal.h b/arch/arm64/include/asm/signal.h
new file mode 100644
index 000000000000..46f9b3c61896
--- /dev/null
+++ b/arch/arm64/include/asm/signal.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ARM64_ASM_SIGNAL_H
+#define __ARM64_ASM_SIGNAL_H
+
+#include <uapi/asm/signal.h>
+#include <uapi/asm/siginfo.h>
+
+static inline unsigned long arch_addr_tag_bits_mask(unsigned long sig,
+						    unsigned long si_code)
+{
+	if (sig == SIGTRAP && si_code == TRAP_BRKPT)
+		return 0;
+	if (sig == SIGSEGV && si_code == SEGV_MTESERR)
+		return 0xfUL << 56;
+	return 0xffUL << 56;
+}
+#define arch_addr_tag_bits_mask arch_addr_tag_bits_mask
+
+#endif
diff --git a/arch/arm64/include/asm/system_misc.h b/arch/arm64/include/asm/system_misc.h
index 1ab63cfbbaf1..673be2d1263c 100644
--- a/arch/arm64/include/asm/system_misc.h
+++ b/arch/arm64/include/asm/system_misc.h
@@ -22,7 +22,7 @@ void die(const char *msg, struct pt_regs *regs, int err);
 
 struct siginfo;
 void arm64_notify_die(const char *str, struct pt_regs *regs,
-		      int signo, int sicode, void __user *addr,
+		      int signo, int sicode, unsigned long far,
 		      int err);
 
 void hook_debug_fault_code(int nr, int (*fn)(unsigned long, unsigned int,
diff --git a/arch/arm64/include/asm/traps.h b/arch/arm64/include/asm/traps.h
index d96dc2c7c09d..54f32a0675df 100644
--- a/arch/arm64/include/asm/traps.h
+++ b/arch/arm64/include/asm/traps.h
@@ -26,9 +26,9 @@ void register_undef_hook(struct undef_hook *hook);
 void unregister_undef_hook(struct undef_hook *hook);
 void force_signal_inject(int signal, int code, unsigned long address, unsigned int err);
 void arm64_notify_segfault(unsigned long addr);
-void arm64_force_sig_fault(int signo, int code, void __user *addr, const char *str);
-void arm64_force_sig_mceerr(int code, void __user *addr, short lsb, const char *str);
-void arm64_force_sig_ptrace_errno_trap(int errno, void __user *addr, const char *str);
+void arm64_force_sig_fault(int signo, int code, unsigned long far, const char *str);
+void arm64_force_sig_mceerr(int code, unsigned long far, short lsb, const char *str);
+void arm64_force_sig_ptrace_errno_trap(int errno, unsigned long far, const char *str);
 
 /*
  * Move regs->pc to next instruction and do necessary setup before it
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index fa76151de6ff..4f3661eeb7ec 100644
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -234,9 +234,8 @@ static void send_user_sigtrap(int si_code)
 	if (interrupts_enabled(regs))
 		local_irq_enable();
 
-	arm64_force_sig_fault(SIGTRAP, si_code,
-			     (void __user *)instruction_pointer(regs),
-			     "User debug trap");
+	arm64_force_sig_fault(SIGTRAP, si_code, instruction_pointer(regs),
+			      "User debug trap");
 }
 
 static int single_step_handler(unsigned long unused, unsigned int esr,
diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c
index 43d4c329775f..dbbddfbf4a72 100644
--- a/arch/arm64/kernel/entry-common.c
+++ b/arch/arm64/kernel/entry-common.c
@@ -22,7 +22,6 @@ static void notrace el1_abort(struct pt_regs *regs, unsigned long esr)
 	unsigned long far = read_sysreg(far_el1);
 
 	local_daif_inherit(regs);
-	far = untagged_addr(far);
 	do_mem_abort(far, esr, regs);
 }
 NOKPROBE_SYMBOL(el1_abort);
@@ -114,7 +113,6 @@ static void notrace el0_da(struct pt_regs *regs, unsigned long esr)
 
 	user_exit_irqoff();
 	local_daif_restore(DAIF_PROCCTX);
-	far = untagged_addr(far);
 	do_mem_abort(far, esr, regs);
 }
 NOKPROBE_SYMBOL(el0_da);
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index f49b349e16a3..8ac487c84e37 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -192,14 +192,11 @@ static void ptrace_hbptriggered(struct perf_event *bp,
 				break;
 			}
 		}
-		arm64_force_sig_ptrace_errno_trap(si_errno,
-						  (void __user *)bkpt->trigger,
+		arm64_force_sig_ptrace_errno_trap(si_errno, bkpt->trigger,
 						  desc);
 	}
 #endif
-	arm64_force_sig_fault(SIGTRAP, TRAP_HWBKPT,
-			      (void __user *)(bkpt->trigger),
-			      desc);
+	arm64_force_sig_fault(SIGTRAP, TRAP_HWBKPT, bkpt->trigger, desc);
 }
 
 /*
diff --git a/arch/arm64/kernel/sys_compat.c b/arch/arm64/kernel/sys_compat.c
index 3c18c2454089..265fe3eb1069 100644
--- a/arch/arm64/kernel/sys_compat.c
+++ b/arch/arm64/kernel/sys_compat.c
@@ -68,7 +68,7 @@ do_compat_cache_op(unsigned long start, unsigned long end, int flags)
  */
 long compat_arm_syscall(struct pt_regs *regs, int scno)
 {
-	void __user *addr;
+	unsigned long addr;
 
 	switch (scno) {
 	/*
@@ -111,8 +111,7 @@ long compat_arm_syscall(struct pt_regs *regs, int scno)
 		break;
 	}
 
-	addr  = (void __user *)instruction_pointer(regs) -
-		(compat_thumb_mode(regs) ? 2 : 4);
+	addr = instruction_pointer(regs) - (compat_thumb_mode(regs) ? 2 : 4);
 
 	arm64_notify_die("Oops - bad compat syscall(2)", regs,
 			 SIGILL, ILL_ILLTRP, addr, scno);
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 8af4e0e85736..f4ddbe9ed3f1 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -170,32 +170,32 @@ 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 signo, int sicode, unsigned long far,
 		      int err)
 {
 	if (user_mode(regs)) {
@@ -203,7 +203,7 @@ void arm64_notify_die(const char *str, struct pt_regs *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);
 	}
@@ -374,7 +374,7 @@ void force_signal_inject(int signal, int code, unsigned long address, unsigned i
 		signal = SIGKILL;
 	}
 
-	arm64_notify_die(desc, regs, signal, code, (void __user *)address, err);
+	arm64_notify_die(desc, regs, signal, code, address, err);
 }
 
 /*
@@ -385,7 +385,7 @@ void arm64_notify_segfault(unsigned long addr)
 	int code;
 
 	mmap_read_lock(current->mm);
-	if (find_vma(current->mm, addr) == NULL)
+	if (find_vma(current->mm, untagged_addr(addr)) == NULL)
 		code = SEGV_MAPERR;
 	else
 		code = SEGV_ACCERR;
@@ -448,12 +448,13 @@ NOKPROBE_SYMBOL(do_ptrauth_fault);
 
 static void user_cache_maint_handler(unsigned int 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 */
@@ -480,7 +481,7 @@ static void user_cache_maint_handler(unsigned int esr, struct pt_regs *regs)
 	}
 
 	if (ret)
-		arm64_notify_segfault(address);
+		arm64_notify_segfault(tagged_address);
 	else
 		arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
 }
@@ -772,7 +773,7 @@ asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr)
  */
 void bad_el0_sync(struct pt_regs *regs, int reason, unsigned int 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;
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 94c99c1c19e3..1d9d678cfc01 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -40,7 +40,7 @@
 #include <asm/traps.h>
 
 struct fault_info {
-	int	(*fn)(unsigned long addr, unsigned int esr,
+	int	(*fn)(unsigned long far, unsigned int esr,
 		      struct pt_regs *regs);
 	int	sig;
 	int	code;
@@ -385,8 +385,11 @@ static void set_thread_esr(unsigned long address, unsigned int esr)
 	current->thread.fault_code = esr;
 }
 
-static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+static void do_bad_area(unsigned long far, unsigned int esr,
+			struct pt_regs *regs)
 {
+	unsigned long addr = untagged_addr(far);
+
 	/*
 	 * If we are in kernel mode at this point, we have no context to
 	 * handle this fault with.
@@ -395,8 +398,7 @@ static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *re
 		const struct fault_info *inf = esr_to_fault_info(esr);
 
 		set_thread_esr(addr, esr);
-		arm64_force_sig_fault(inf->sig, inf->code, (void __user *)addr,
-				      inf->name);
+		arm64_force_sig_fault(inf->sig, inf->code, far, inf->name);
 	} else {
 		__do_kernel_fault(addr, esr, regs);
 	}
@@ -448,7 +450,7 @@ static bool is_write_abort(unsigned int esr)
 	return (esr & ESR_ELx_WNR) && !(esr & ESR_ELx_CM);
 }
 
-static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
+static int __kprobes do_page_fault(unsigned long far, unsigned int esr,
 				   struct pt_regs *regs)
 {
 	const struct fault_info *inf;
@@ -456,6 +458,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
 	vm_fault_t fault;
 	unsigned long vm_flags = VM_ACCESS_FLAGS;
 	unsigned int mm_flags = FAULT_FLAG_DEFAULT;
+	unsigned long addr = untagged_addr(far);
 
 	if (kprobe_page_fault(regs, esr))
 		return 0;
@@ -567,8 +570,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
 		 * We had some memory, but were unable to successfully fix up
 		 * this page fault.
 		 */
-		arm64_force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)addr,
-				      inf->name);
+		arm64_force_sig_fault(SIGBUS, BUS_ADRERR, far, inf->name);
 	} else if (fault & (VM_FAULT_HWPOISON_LARGE | VM_FAULT_HWPOISON)) {
 		unsigned int lsb;
 
@@ -576,8 +578,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
 		if (fault & VM_FAULT_HWPOISON_LARGE)
 			lsb = hstate_index_to_shift(VM_FAULT_GET_HINDEX(fault));
 
-		arm64_force_sig_mceerr(BUS_MCEERR_AR, (void __user *)addr, lsb,
-				       inf->name);
+		arm64_force_sig_mceerr(BUS_MCEERR_AR, far, lsb, inf->name);
 	} else {
 		/*
 		 * Something tried to access memory that isn't in our memory
@@ -585,8 +586,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
 		 */
 		arm64_force_sig_fault(SIGSEGV,
 				      fault == VM_FAULT_BADACCESS ? SEGV_ACCERR : SEGV_MAPERR,
-				      (void __user *)addr,
-				      inf->name);
+				      far, inf->name);
 	}
 
 	return 0;
@@ -596,33 +596,35 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
 	return 0;
 }
 
-static int __kprobes do_translation_fault(unsigned long addr,
+static int __kprobes do_translation_fault(unsigned long far,
 					  unsigned int esr,
 					  struct pt_regs *regs)
 {
+	unsigned long addr = untagged_addr(far);
+
 	if (is_ttbr0_addr(addr))
-		return do_page_fault(addr, esr, regs);
+		return do_page_fault(far, esr, regs);
 
-	do_bad_area(addr, esr, regs);
+	do_bad_area(far, esr, regs);
 	return 0;
 }
 
-static int do_alignment_fault(unsigned long addr, unsigned int esr,
+static int do_alignment_fault(unsigned long far, unsigned int esr,
 			      struct pt_regs *regs)
 {
-	do_bad_area(addr, esr, regs);
+	do_bad_area(far, esr, regs);
 	return 0;
 }
 
-static int do_bad(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+static int do_bad(unsigned long far, unsigned int esr, struct pt_regs *regs)
 {
 	return 1; /* "fault" */
 }
 
-static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+static int do_sea(unsigned long far, unsigned int esr, struct pt_regs *regs)
 {
 	const struct fault_info *inf;
-	void __user *siaddr;
+	unsigned long siaddr;
 
 	inf = esr_to_fault_info(esr);
 
@@ -635,18 +637,23 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 	}
 
 	if (esr & ESR_ELx_FnV)
-		siaddr = NULL;
+		siaddr = 0;
 	else
-		siaddr  = (void __user *)addr;
+		siaddr  = untagged_addr(far);
 	arm64_notify_die(inf->name, regs, inf->sig, inf->code, siaddr, esr);
 
 	return 0;
 }
 
-static int do_tag_check_fault(unsigned long addr, unsigned int esr,
+static int do_tag_check_fault(unsigned long far, unsigned int esr,
 			      struct pt_regs *regs)
 {
-	do_bad_area(addr, esr, regs);
+	/*
+	 * The architecture specifies that bits 63:60 of FAR_EL1 are UNKNOWN for tag
+	 * check faults. Mask them out now so that userspace doesn't see them.
+	 */
+	far &= (1UL << 60) - 1;
+	do_bad_area(far, esr, regs);
 	return 0;
 }
 
@@ -717,11 +724,12 @@ static const struct fault_info fault_info[] = {
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 63"			},
 };
 
-void do_mem_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+void do_mem_abort(unsigned long far, unsigned int esr, struct pt_regs *regs)
 {
 	const struct fault_info *inf = esr_to_fault_info(esr);
+	unsigned long addr = untagged_addr(far);
 
-	if (!inf->fn(addr, esr, regs))
+	if (!inf->fn(far, esr, regs))
 		return;
 
 	if (!user_mode(regs)) {
@@ -730,8 +738,7 @@ void do_mem_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 		show_pte(addr);
 	}
 
-	arm64_notify_die(inf->name, regs,
-			 inf->sig, inf->code, (void __user *)addr, esr);
+	arm64_notify_die(inf->name, regs, inf->sig, inf->code, addr, esr);
 }
 NOKPROBE_SYMBOL(do_mem_abort);
 
@@ -744,8 +751,8 @@ NOKPROBE_SYMBOL(do_el0_irq_bp_hardening);
 
 void do_sp_pc_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 {
-	arm64_notify_die("SP/PC alignment exception", regs,
-			 SIGBUS, BUS_ADRALN, (void __user *)addr, esr);
+	arm64_notify_die("SP/PC alignment exception", regs, SIGBUS, BUS_ADRALN,
+			 addr, esr);
 }
 NOKPROBE_SYMBOL(do_sp_pc_abort);
 
@@ -871,8 +878,7 @@ void do_debug_exception(unsigned long addr_if_watchpoint, unsigned int esr,
 		arm64_apply_bp_hardening();
 
 	if (inf->fn(addr_if_watchpoint, esr, regs)) {
-		arm64_notify_die(inf->name, regs,
-				 inf->sig, inf->code, (void __user *)pc, esr);
+		arm64_notify_die(inf->name, regs, inf->sig, inf->code, pc, esr);
 	}
 
 	debug_exception_exit(regs);
diff --git a/arch/x86/kernel/signal_compat.c b/arch/x86/kernel/signal_compat.c
index 243a8cc3b41b..aa33674a4972 100644
--- a/arch/x86/kernel/signal_compat.c
+++ b/arch/x86/kernel/signal_compat.c
@@ -121,8 +121,8 @@ static inline void signal_compat_build_tests(void)
 #endif
 
 	CHECK_CSI_OFFSET(_sigfault);
-	CHECK_CSI_SIZE  (_sigfault, 8*sizeof(int));
-	CHECK_SI_SIZE   (_sigfault, 16*sizeof(int));
+	CHECK_CSI_SIZE  (_sigfault, 10*sizeof(int));
+	CHECK_SI_SIZE   (_sigfault, 20*sizeof(int));
 
 	BUILD_BUG_ON(offsetof(siginfo_t, si_addr) != 0x10);
 	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_addr) != 0x0C);
@@ -141,6 +141,11 @@ static inline void signal_compat_build_tests(void)
 	BUILD_BUG_ON(offsetof(siginfo_t, si_xflags) != 0x48);
 	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_xflags) != 0x28);
 
+	BUILD_BUG_ON(offsetof(siginfo_t, si_addr_tag_bits) != 0x50);
+	BUILD_BUG_ON(offsetof(siginfo_t, si_addr_tag_bits_mask) != 0x58);
+	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_addr_tag_bits) != 0x2C);
+	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_addr_tag_bits_mask) != 0x30);
+
 	CHECK_CSI_OFFSET(_sigpoll);
 	CHECK_CSI_SIZE  (_sigpoll, 2*sizeof(int));
 	CHECK_SI_SIZE   (_sigpoll, 4*sizeof(int));
diff --git a/include/linux/compat.h b/include/linux/compat.h
index ea77a24ce6a2..345d029adadc 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -239,6 +239,8 @@ typedef struct compat_siginfo {
 				compat_uptr_t _pad[6];
 			};
 			u32 _xflags;
+			compat_uptr_t _addr_tag_bits;
+			compat_uptr_t _addr_tag_bits_mask;
 		} _sigfault;
 
 		/* SIGPOLL */
diff --git a/include/linux/signal.h b/include/linux/signal.h
index 9b7fef0c559d..e12f211f5c12 100644
--- a/include/linux/signal.h
+++ b/include/linux/signal.h
@@ -480,4 +480,20 @@ struct seq_file;
 extern void render_sigset_t(struct seq_file *, const char *, sigset_t *);
 #endif
 
+#ifndef arch_addr_tag_bits_mask
+/*
+ * Given a signal and si_code which correspond to the _sigfault union member,
+ * if tag bits are present in the fault address which must appear in
+ * si_addr_tag_bits instead of si_addr, this hook must return a bitmask where 1
+ * corresponds to bits appearing in si_addr_tag_bits and 0 corresponds to bits
+ * appearing in si_addr. The value returned by this function will also be
+ * available in si_addr_tag_bits_mask.
+ */
+static inline unsigned long arch_addr_tag_bits_mask(unsigned long sig,
+						    unsigned long si_code)
+{
+	return 0;
+}
+#endif
+
 #endif /* _LINUX_SIGNAL_H */
diff --git a/include/uapi/asm-generic/siginfo.h b/include/uapi/asm-generic/siginfo.h
index 8158d5df666a..e5fe256c4979 100644
--- a/include/uapi/asm-generic/siginfo.h
+++ b/include/uapi/asm-generic/siginfo.h
@@ -94,6 +94,8 @@ union __sifields {
 			void *_pad[6];
 		};
 		__u32 _xflags;
+		unsigned long _addr_tag_bits;
+		unsigned long _addr_tag_bits_mask;
 	} _sigfault;
 
 	/* SIGPOLL */
@@ -156,6 +158,8 @@ typedef struct siginfo {
 #define si_addr_lsb	_sifields._sigfault._addr_lsb
 /* si_xflags is only valid if 0 < si_code < SI_KERNEL */
 #define si_xflags	_sifields._sigfault._xflags
+#define si_addr_tag_bits	_sifields._sigfault._addr_tag_bits
+#define si_addr_tag_bits_mask	_sifields._sigfault._addr_tag_bits_mask
 #define si_lower	_sifields._sigfault._addr_bnd._lower
 #define si_upper	_sifields._sigfault._addr_bnd._upper
 #define si_pkey		_sifields._sigfault._addr_pkey._pkey
@@ -298,6 +302,12 @@ typedef struct siginfo {
 #define EMT_TAGOVF	1	/* tag overflow */
 #define NSIGEMT		1
 
+/*
+ * SIGILL, SIGFPE, SIGSEGV, SIGBUS, SIGTRAP, SIGEMT si_xflags
+ */
+#define SIXFLAG_ADDR_TAG_BITS	1
+/* si_addr_tag_bits{,_mask} fields valid */
+
 /*
  * sigevent definitions
  * 
diff --git a/kernel/signal.c b/kernel/signal.c
index 5c715a01942f..f41b40c9caf1 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1652,11 +1652,16 @@ void force_sigsegv(int sig)
 static void set_sigfault_common_fields(struct kernel_siginfo *info, int sig,
 				       int code, void __user *addr)
 {
+	unsigned long addr_long = (unsigned long)addr;
+	unsigned long tag_bits_mask = arch_addr_tag_bits_mask(sig, code);
+
 	info->si_signo = sig;
 	info->si_errno = 0;
 	info->si_code = code;
-	info->si_addr = addr;
-	info->si_xflags = 0;
+	info->si_addr = (void __user *)(addr_long & ~tag_bits_mask);
+	info->si_xflags = SIXFLAG_ADDR_TAG_BITS;
+	info->si_addr_tag_bits = addr_long & tag_bits_mask;
+	info->si_addr_tag_bits_mask = tag_bits_mask;
 }
 
 int force_sig_fault_to_task(int sig, int code, void __user *addr
@@ -3271,6 +3276,13 @@ void copy_siginfo_to_external32(struct compat_siginfo *to,
 		to->si_trapno = from->si_trapno;
 #endif
 		to->si_xflags = from->si_xflags;
+		/*
+		 * These assignments involve a truncation, but as with si_addr
+		 * they will be derived from a 32-bit fault address so we
+		 * should not expect any truncation in practice.
+		 */
+		to->si_addr_tag_bits = from->si_addr_tag_bits;
+		to->si_addr_tag_bits_mask = from->si_addr_tag_bits_mask;
 	}
 
 	switch (layout) {
@@ -3347,6 +3359,8 @@ static int post_copy_siginfo_from_user32(kernel_siginfo_t *to,
 		to->si_trapno = from->si_trapno;
 #endif
 		to->si_xflags = from->si_xflags;
+		to->si_addr_tag_bits = from->si_addr_tag_bits;
+		to->si_addr_tag_bits_mask = from->si_addr_tag_bits_mask;
 	}
 
 	switch (layout) {
