1 files changed, 270 insertions, 226 deletions

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 349c488765ca..be9dab2c7d6a 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -23,6 +23,7 @@
 #include <linux/sched/debug.h>
 #include <linux/highmem.h>
 #include <linux/perf_event.h>
+#include <linux/pkeys.h>
 #include <linux/preempt.h>
 #include <linux/hugetlb.h>
 
@@ -30,6 +31,7 @@
 #include <asm/bug.h>
 #include <asm/cmpxchg.h>
 #include <asm/cpufeature.h>
+#include <asm/efi.h>
 #include <asm/exception.h>
 #include <asm/daifflags.h>
 #include <asm/debug-monitors.h>
@@ -43,7 +45,7 @@
 #include <asm/traps.h>
 
 struct fault_info {
-	int	(*fn)(unsigned long far, unsigned int esr,
+	int	(*fn)(unsigned long far, unsigned long esr,
 		      struct pt_regs *regs);
 	int	sig;
 	int	code;
@@ -51,20 +53,16 @@ struct fault_info {
 };
 
 static const struct fault_info fault_info[];
-static struct fault_info debug_fault_info[];
 
-static inline const struct fault_info *esr_to_fault_info(unsigned int esr)
+static inline const struct fault_info *esr_to_fault_info(unsigned long esr)
 {
 	return fault_info + (esr & ESR_ELx_FSC);
 }
 
-static inline const struct fault_info *esr_to_debug_fault_info(unsigned int esr)
+static void data_abort_decode(unsigned long esr)
 {
-	return debug_fault_info + DBG_ESR_EVT(esr);
-}
+	unsigned long iss2 = ESR_ELx_ISS2(esr);
 
-static void data_abort_decode(unsigned int esr)
-{
 	pr_alert("Data abort info:\n");
 
 	if (esr & ESR_ELx_ISV) {
@@ -77,19 +75,28 @@ static void data_abort_decode(unsigned int esr)
 			 (esr & ESR_ELx_SF) >> ESR_ELx_SF_SHIFT,
 			 (esr & ESR_ELx_AR) >> ESR_ELx_AR_SHIFT);
 	} else {
-		pr_alert("  ISV = 0, ISS = 0x%08lx\n", esr & ESR_ELx_ISS_MASK);
+		pr_alert("  ISV = 0, ISS = 0x%08lx, ISS2 = 0x%08lx\n",
+			 esr & ESR_ELx_ISS_MASK, iss2);
 	}
 
-	pr_alert("  CM = %lu, WnR = %lu\n",
+	pr_alert("  CM = %lu, WnR = %lu, TnD = %lu, TagAccess = %lu\n",
 		 (esr & ESR_ELx_CM) >> ESR_ELx_CM_SHIFT,
-		 (esr & ESR_ELx_WNR) >> ESR_ELx_WNR_SHIFT);
+		 (esr & ESR_ELx_WNR) >> ESR_ELx_WNR_SHIFT,
+		 (iss2 & ESR_ELx_TnD) >> ESR_ELx_TnD_SHIFT,
+		 (iss2 & ESR_ELx_TagAccess) >> ESR_ELx_TagAccess_SHIFT);
+
+	pr_alert("  GCS = %ld, Overlay = %lu, DirtyBit = %lu, Xs = %llu\n",
+		 (iss2 & ESR_ELx_GCS) >> ESR_ELx_GCS_SHIFT,
+		 (iss2 & ESR_ELx_Overlay) >> ESR_ELx_Overlay_SHIFT,
+		 (iss2 & ESR_ELx_DirtyBit) >> ESR_ELx_DirtyBit_SHIFT,
+		 (iss2 & ESR_ELx_Xs_MASK) >> ESR_ELx_Xs_SHIFT);
 }
 
-static void mem_abort_decode(unsigned int esr)
+static void mem_abort_decode(unsigned long esr)
 {
 	pr_alert("Mem abort info:\n");
 
-	pr_alert("  ESR = 0x%08x\n", esr);
+	pr_alert("  ESR = 0x%016lx\n", esr);
 	pr_alert("  EC = 0x%02lx: %s, IL = %u bits\n",
 		 ESR_ELx_EC(esr), esr_get_class_string(esr),
 		 (esr & ESR_ELx_IL) ? 32 : 16);
@@ -99,7 +106,7 @@ static void mem_abort_decode(unsigned int esr)
 	pr_alert("  EA = %lu, S1PTW = %lu\n",
 		 (esr & ESR_ELx_EA) >> ESR_ELx_EA_SHIFT,
 		 (esr & ESR_ELx_S1PTW) >> ESR_ELx_S1PTW_SHIFT);
-	pr_alert("  FSC = 0x%02x: %s\n", (esr & ESR_ELx_FSC),
+	pr_alert("  FSC = 0x%02lx: %s\n", (esr & ESR_ELx_FSC),
 		 esr_to_fault_info(esr)->name);
 
 	if (esr_is_data_abort(esr))
@@ -176,7 +183,10 @@ static void show_pte(unsigned long addr)
 			break;
 
 		ptep = pte_offset_map(pmdp, addr);
-		pte = READ_ONCE(*ptep);
+		if (!ptep)
+			break;
+
+		pte = __ptep_get(ptep);
 		pr_cont(", pte=%016llx", pte_val(pte));
 		pte_unmap(ptep);
 	} while(0);
@@ -190,16 +200,16 @@ static void show_pte(unsigned long addr)
  *
  * It needs to cope with hardware update of the accessed/dirty state by other
  * agents in the system and can safely skip the __sync_icache_dcache() call as,
- * like set_pte_at(), the PTE is never changed from no-exec to exec here.
+ * like __set_ptes(), the PTE is never changed from no-exec to exec here.
  *
  * Returns whether or not the PTE actually changed.
  */
-int ptep_set_access_flags(struct vm_area_struct *vma,
-			  unsigned long address, pte_t *ptep,
-			  pte_t entry, int dirty)
+int __ptep_set_access_flags(struct vm_area_struct *vma,
+			    unsigned long address, pte_t *ptep,
+			    pte_t entry, int dirty)
 {
 	pteval_t old_pteval, pteval;
-	pte_t pte = READ_ONCE(*ptep);
+	pte_t pte = __ptep_get(ptep);
 
 	if (pte_same(pte, entry))
 		return 0;
@@ -223,49 +233,50 @@ int ptep_set_access_flags(struct vm_area_struct *vma,
 		pteval = cmpxchg_relaxed(&pte_val(*ptep), old_pteval, pteval);
 	} while (pteval != old_pteval);
 
-	/* Invalidate a stale read-only entry */
+	/*
+	 * Invalidate the local stale read-only entry.  Remote stale entries
+	 * may still cause page faults and be invalidated via
+	 * flush_tlb_fix_spurious_fault().
+	 */
 	if (dirty)
-		flush_tlb_page(vma, address);
+		local_flush_tlb_page(vma, address);
 	return 1;
 }
 
-static bool is_el1_instruction_abort(unsigned int esr)
+static bool is_el1_instruction_abort(unsigned long esr)
 {
 	return ESR_ELx_EC(esr) == ESR_ELx_EC_IABT_CUR;
 }
 
-static bool is_el1_data_abort(unsigned int esr)
+static bool is_el1_data_abort(unsigned long esr)
 {
 	return ESR_ELx_EC(esr) == ESR_ELx_EC_DABT_CUR;
 }
 
-static inline bool is_el1_permission_fault(unsigned long addr, unsigned int esr,
+static inline bool is_el1_permission_fault(unsigned long addr, unsigned long esr,
 					   struct pt_regs *regs)
 {
-	unsigned int fsc_type = esr & ESR_ELx_FSC_TYPE;
-
 	if (!is_el1_data_abort(esr) && !is_el1_instruction_abort(esr))
 		return false;
 
-	if (fsc_type == ESR_ELx_FSC_PERM)
+	if (esr_fsc_is_permission_fault(esr))
 		return true;
 
 	if (is_ttbr0_addr(addr) && system_uses_ttbr0_pan())
-		return fsc_type == ESR_ELx_FSC_FAULT &&
+		return esr_fsc_is_translation_fault(esr) &&
 			(regs->pstate & PSR_PAN_BIT);
 
 	return false;
 }
 
 static bool __kprobes is_spurious_el1_translation_fault(unsigned long addr,
-							unsigned int esr,
+							unsigned long esr,
 							struct pt_regs *regs)
 {
 	unsigned long flags;
 	u64 par, dfsc;
 
-	if (!is_el1_data_abort(esr) ||
-	    (esr & ESR_ELx_FSC_TYPE) != ESR_ELx_FSC_FAULT)
+	if (!is_el1_data_abort(esr) || !esr_fsc_is_translation_fault(esr))
 		return false;
 
 	local_irq_save(flags);
@@ -286,56 +297,45 @@ static bool __kprobes is_spurious_el1_translation_fault(unsigned long addr,
 	 * treat the translation fault as spurious.
 	 */
 	dfsc = FIELD_GET(SYS_PAR_EL1_FST, par);
-	return (dfsc & ESR_ELx_FSC_TYPE) != ESR_ELx_FSC_FAULT;
+	return !esr_fsc_is_translation_fault(dfsc);
 }
 
 static void die_kernel_fault(const char *msg, unsigned long addr,
-			     unsigned int esr, struct pt_regs *regs)
+			     unsigned long esr, struct pt_regs *regs)
 {
 	bust_spinlocks(1);
 
 	pr_alert("Unable to handle kernel %s at virtual address %016lx\n", msg,
 		 addr);
 
+	kasan_non_canonical_hook(addr);
+
 	mem_abort_decode(esr);
 
 	show_pte(addr);
 	die("Oops", regs, esr);
 	bust_spinlocks(0);
-	do_exit(SIGKILL);
+	make_task_dead(SIGKILL);
 }
 
 #ifdef CONFIG_KASAN_HW_TAGS
-static void report_tag_fault(unsigned long addr, unsigned int esr,
+static void report_tag_fault(unsigned long addr, unsigned long esr,
 			     struct pt_regs *regs)
 {
-	static bool reported;
-	bool is_write;
-
-	if (READ_ONCE(reported))
-		return;
-
-	/*
-	 * This is used for KASAN tests and assumes that no MTE faults
-	 * happened before running the tests.
-	 */
-	if (mte_report_once())
-		WRITE_ONCE(reported, true);
-
 	/*
 	 * SAS bits aren't set for all faults reported in EL1, so we can't
 	 * find out access size.
 	 */
-	is_write = !!(esr & ESR_ELx_WNR);
-	kasan_report(addr, 0, is_write, regs->pc);
+	bool is_write = !!(esr & ESR_ELx_WNR);
+	kasan_report((void *)addr, 0, is_write, regs->pc);
 }
 #else
 /* Tag faults aren't enabled without CONFIG_KASAN_HW_TAGS. */
-static inline void report_tag_fault(unsigned long addr, unsigned int esr,
+static inline void report_tag_fault(unsigned long addr, unsigned long esr,
 				    struct pt_regs *regs) { }
 #endif
 
-static void do_tag_recovery(unsigned long addr, unsigned int esr,
+static void do_tag_recovery(unsigned long addr, unsigned long esr,
 			   struct pt_regs *regs)
 {
 
@@ -346,13 +346,14 @@ static void do_tag_recovery(unsigned long addr, unsigned int esr,
 	 * It will be done lazily on the other CPUs when they will hit a
 	 * tag fault.
 	 */
-	sysreg_clear_set(sctlr_el1, SCTLR_ELx_TCF_MASK, SCTLR_ELx_TCF_NONE);
+	sysreg_clear_set(sctlr_el1, SCTLR_EL1_TCF_MASK,
+			 SYS_FIELD_PREP_ENUM(SCTLR_EL1, TCF, NONE));
 	isb();
 }
 
-static bool is_el1_mte_sync_tag_check_fault(unsigned int esr)
+static bool is_el1_mte_sync_tag_check_fault(unsigned long esr)
 {
-	unsigned int fsc = esr & ESR_ELx_FSC;
+	unsigned long fsc = esr & ESR_ELx_FSC;
 
 	if (!is_el1_data_abort(esr))
 		return false;
@@ -363,7 +364,7 @@ static bool is_el1_mte_sync_tag_check_fault(unsigned int esr)
 	return false;
 }
 
-static void __do_kernel_fault(unsigned long addr, unsigned int esr,
+static void __do_kernel_fault(unsigned long addr, unsigned long esr,
 			      struct pt_regs *regs)
 {
 	const char *msg;
@@ -372,7 +373,7 @@ static void __do_kernel_fault(unsigned long addr, unsigned int esr,
 	 * Are we prepared to handle this kernel fault?
 	 * We are almost certainly not prepared to handle instruction faults.
 	 */
-	if (!is_el1_instruction_abort(esr) && fixup_exception(regs))
+	if (!is_el1_instruction_abort(esr) && fixup_exception(regs, esr))
 		return;
 
 	if (WARN_RATELIMIT(is_spurious_el1_translation_fault(addr, esr, regs),
@@ -395,16 +396,20 @@ static void __do_kernel_fault(unsigned long addr, unsigned int esr,
 	} else if (addr < PAGE_SIZE) {
 		msg = "NULL pointer dereference";
 	} else {
-		if (kfence_handle_page_fault(addr, esr & ESR_ELx_WNR, regs))
+		if (esr_fsc_is_translation_fault(esr) &&
+		    kfence_handle_page_fault(addr, esr & ESR_ELx_WNR, regs))
 			return;
 
 		msg = "paging request";
 	}
 
+	if (efi_runtime_fixup_exception(regs, msg))
+		return;
+
 	die_kernel_fault(msg, addr, esr, regs);
 }
 
-static void set_thread_esr(unsigned long address, unsigned int esr)
+static void set_thread_esr(unsigned long address, unsigned long esr)
 {
 	current->thread.fault_address = address;
 
@@ -452,7 +457,7 @@ static void set_thread_esr(unsigned long address, unsigned int esr)
 			 * exception level). Fail safe by not providing an ESR
 			 * context record at all.
 			 */
-			WARN(1, "ESR 0x%x is not DABT or IABT from EL0\n", esr);
+			WARN(1, "ESR 0x%lx is not DABT or IABT from EL0\n", esr);
 			esr = 0;
 			break;
 		}
@@ -461,7 +466,7 @@ static void set_thread_esr(unsigned long address, unsigned int esr)
 	current->thread.fault_code = esr;
 }
 
-static void do_bad_area(unsigned long far, unsigned int esr,
+static void do_bad_area(unsigned long far, unsigned long esr,
 			struct pt_regs *regs)
 {
 	unsigned long addr = untagged_addr(far);
@@ -480,39 +485,44 @@ static void do_bad_area(unsigned long far, unsigned int esr,
 	}
 }
 
-#define VM_FAULT_BADMAP		0x010000
-#define VM_FAULT_BADACCESS	0x020000
-
-static vm_fault_t __do_page_fault(struct mm_struct *mm, unsigned long addr,
-				  unsigned int mm_flags, unsigned long vm_flags,
-				  struct pt_regs *regs)
+static bool fault_from_pkey(struct vm_area_struct *vma, unsigned int mm_flags)
 {
-	struct vm_area_struct *vma = find_vma(mm, addr);
-
-	if (unlikely(!vma))
-		return VM_FAULT_BADMAP;
+	if (!system_supports_poe())
+		return false;
 
 	/*
-	 * Ok, we have a good vm_area for this memory access, so we can handle
-	 * it.
+	 * We do not check whether an Overlay fault has occurred because we
+	 * cannot make a decision based solely on its value:
+	 *
+	 * - If Overlay is set, a fault did occur due to POE, but it may be
+	 *   spurious in those cases where we update POR_EL0 without ISB (e.g.
+	 *   on context-switch). We would then need to manually check POR_EL0
+	 *   against vma_pkey(vma), which is exactly what
+	 *   arch_vma_access_permitted() does.
+	 *
+	 * - If Overlay is not set, we may still need to report a pkey fault.
+	 *   This is the case if an access was made within a mapping but with no
+	 *   page mapped, and POR_EL0 forbids the access (according to
+	 *   vma_pkey()). Such access will result in a SIGSEGV regardless
+	 *   because core code checks arch_vma_access_permitted(), but in order
+	 *   to report the correct error code - SEGV_PKUERR - we must handle
+	 *   that case here.
 	 */
-	if (unlikely(vma->vm_start > addr)) {
-		if (!(vma->vm_flags & VM_GROWSDOWN))
-			return VM_FAULT_BADMAP;
-		if (expand_stack(vma, addr))
-			return VM_FAULT_BADMAP;
-	}
+	return !arch_vma_access_permitted(vma,
+			mm_flags & FAULT_FLAG_WRITE,
+			mm_flags & FAULT_FLAG_INSTRUCTION,
+			false);
+}
 
-	/*
-	 * Check that the permissions on the VMA allow for the fault which
-	 * occurred.
-	 */
-	if (!(vma->vm_flags & vm_flags))
-		return VM_FAULT_BADACCESS;
-	return handle_mm_fault(vma, addr, mm_flags, regs);
+static bool is_gcs_fault(unsigned long esr)
+{
+	if (!esr_is_data_abort(esr))
+		return false;
+
+	return ESR_ELx_ISS2(esr) & ESR_ELx_GCS;
 }
 
-static bool is_el0_instruction_abort(unsigned int esr)
+static bool is_el0_instruction_abort(unsigned long esr)
 {
 	return ESR_ELx_EC(esr) == ESR_ELx_EC_IABT_LOW;
 }
@@ -521,20 +531,40 @@ static bool is_el0_instruction_abort(unsigned int esr)
  * Note: not valid for EL1 DC IVAC, but we never use that such that it
  * should fault. EL0 cannot issue DC IVAC (undef).
  */
-static bool is_write_abort(unsigned int esr)
+static bool is_write_abort(unsigned long esr)
 {
 	return (esr & ESR_ELx_WNR) && !(esr & ESR_ELx_CM);
 }
 
-static int __kprobes do_page_fault(unsigned long far, unsigned int esr,
+static bool is_invalid_gcs_access(struct vm_area_struct *vma, u64 esr)
+{
+	if (!system_supports_gcs())
+		return false;
+
+	if (unlikely(is_gcs_fault(esr))) {
+		/* GCS accesses must be performed on a GCS page */
+		if (!(vma->vm_flags & VM_SHADOW_STACK))
+			return true;
+	} else if (unlikely(vma->vm_flags & VM_SHADOW_STACK)) {
+		/* Only GCS operations can write to a GCS page */
+		return esr_is_data_abort(esr) && is_write_abort(esr);
+	}
+
+	return false;
+}
+
+static int __kprobes do_page_fault(unsigned long far, unsigned long esr,
 				   struct pt_regs *regs)
 {
 	const struct fault_info *inf;
 	struct mm_struct *mm = current->mm;
 	vm_fault_t fault;
-	unsigned long vm_flags;
+	vm_flags_t vm_flags;
 	unsigned int mm_flags = FAULT_FLAG_DEFAULT;
 	unsigned long addr = untagged_addr(far);
+	struct vm_area_struct *vma;
+	int si_code;
+	int pkey = -1;
 
 	if (kprobe_page_fault(regs, esr))
 		return 0;
@@ -559,6 +589,14 @@ static int __kprobes do_page_fault(unsigned long far, unsigned int esr,
 		/* It was exec fault */
 		vm_flags = VM_EXEC;
 		mm_flags |= FAULT_FLAG_INSTRUCTION;
+	} else if (is_gcs_fault(esr)) {
+		/*
+		 * The GCS permission on a page implies both read and
+		 * write so always handle any GCS fault as a write fault,
+		 * we need to trigger CoW even for GCS reads.
+		 */
+		vm_flags = VM_WRITE;
+		mm_flags |= FAULT_FLAG_WRITE;
 	} else if (is_write_abort(esr)) {
 		/* It was write fault */
 		vm_flags = VM_WRITE;
@@ -569,7 +607,7 @@ static int __kprobes do_page_fault(unsigned long far, unsigned int esr,
 		/* Write implies read */
 		vm_flags |= VM_WRITE;
 		/* If EPAN is absent then exec implies read */
-		if (!cpus_have_const_cap(ARM64_HAS_EPAN))
+		if (!alternative_has_cap_unlikely(ARM64_HAS_EPAN))
 			vm_flags |= VM_EXEC;
 	}
 
@@ -578,38 +616,88 @@ static int __kprobes do_page_fault(unsigned long far, unsigned int esr,
 			die_kernel_fault("execution of user memory",
 					 addr, esr, regs);
 
-		if (!search_exception_tables(regs->pc))
+		if (!insn_may_access_user(regs->pc, esr))
 			die_kernel_fault("access to user memory outside uaccess routines",
 					 addr, esr, regs);
 	}
 
 	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr);
 
-	/*
-	 * As per x86, we may deadlock here. However, since the kernel only
-	 * validly references user space from well defined areas of the code,
-	 * we can bug out early if this is from code which shouldn't.
-	 */
-	if (!mmap_read_trylock(mm)) {
-		if (!user_mode(regs) && !search_exception_tables(regs->pc))
+	if (!(mm_flags & FAULT_FLAG_USER))
+		goto lock_mmap;
+
+	vma = lock_vma_under_rcu(mm, addr);
+	if (!vma)
+		goto lock_mmap;
+
+	if (is_invalid_gcs_access(vma, esr)) {
+		vma_end_read(vma);
+		fault = 0;
+		si_code = SEGV_ACCERR;
+		goto bad_area;
+	}
+
+	if (!(vma->vm_flags & vm_flags)) {
+		vma_end_read(vma);
+		fault = 0;
+		si_code = SEGV_ACCERR;
+		count_vm_vma_lock_event(VMA_LOCK_SUCCESS);
+		goto bad_area;
+	}
+
+	if (fault_from_pkey(vma, mm_flags)) {
+		pkey = vma_pkey(vma);
+		vma_end_read(vma);
+		fault = 0;
+		si_code = SEGV_PKUERR;
+		count_vm_vma_lock_event(VMA_LOCK_SUCCESS);
+		goto bad_area;
+	}
+
+	fault = handle_mm_fault(vma, addr, mm_flags | FAULT_FLAG_VMA_LOCK, regs);
+	if (!(fault & (VM_FAULT_RETRY | VM_FAULT_COMPLETED)))
+		vma_end_read(vma);
+
+	if (!(fault & VM_FAULT_RETRY)) {
+		count_vm_vma_lock_event(VMA_LOCK_SUCCESS);
+		goto done;
+	}
+	count_vm_vma_lock_event(VMA_LOCK_RETRY);
+	if (fault & VM_FAULT_MAJOR)
+		mm_flags |= FAULT_FLAG_TRIED;
+
+	/* Quick path to respond to signals */
+	if (fault_signal_pending(fault, regs)) {
+		if (!user_mode(regs))
 			goto no_context;
+		return 0;
+	}
+lock_mmap:
+
 retry:
-		mmap_read_lock(mm);
-	} else {
-		/*
-		 * The above mmap_read_trylock() might have succeeded in which
-		 * case, we'll have missed the might_sleep() from down_read().
-		 */
-		might_sleep();
-#ifdef CONFIG_DEBUG_VM
-		if (!user_mode(regs) && !search_exception_tables(regs->pc)) {
-			mmap_read_unlock(mm);
-			goto no_context;
-		}
-#endif
+	vma = lock_mm_and_find_vma(mm, addr, regs);
+	if (unlikely(!vma)) {
+		fault = 0;
+		si_code = SEGV_MAPERR;
+		goto bad_area;
 	}
 
-	fault = __do_page_fault(mm, addr, mm_flags, vm_flags, regs);
+	if (!(vma->vm_flags & vm_flags)) {
+		mmap_read_unlock(mm);
+		fault = 0;
+		si_code = SEGV_ACCERR;
+		goto bad_area;
+	}
+
+	if (fault_from_pkey(vma, mm_flags)) {
+		pkey = vma_pkey(vma);
+		mmap_read_unlock(mm);
+		fault = 0;
+		si_code = SEGV_PKUERR;
+		goto bad_area;
+	}
+
+	fault = handle_mm_fault(vma, addr, mm_flags, regs);
 
 	/* Quick path to respond to signals */
 	if (fault_signal_pending(fault, regs)) {
@@ -618,21 +706,23 @@ retry:
 		return 0;
 	}
 
+	/* The fault is fully completed (including releasing mmap lock) */
+	if (fault & VM_FAULT_COMPLETED)
+		return 0;
+
 	if (fault & VM_FAULT_RETRY) {
-		if (mm_flags & FAULT_FLAG_ALLOW_RETRY) {
-			mm_flags |= FAULT_FLAG_TRIED;
-			goto retry;
-		}
+		mm_flags |= FAULT_FLAG_TRIED;
+		goto retry;
 	}
 	mmap_read_unlock(mm);
 
-	/*
-	 * Handle the "normal" (no error) case first.
-	 */
-	if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP |
-			      VM_FAULT_BADACCESS))))
+done:
+	/* Handle the "normal" (no error) case first. */
+	if (likely(!(fault & VM_FAULT_ERROR)))
 		return 0;
 
+	si_code = SEGV_MAPERR;
+bad_area:
 	/*
 	 * If we are in kernel mode at this point, we have no context to
 	 * handle this fault with.
@@ -668,12 +758,22 @@ retry:
 		arm64_force_sig_mceerr(BUS_MCEERR_AR, far, lsb, inf->name);
 	} else {
 		/*
-		 * Something tried to access memory that isn't in our memory
-		 * map.
+		 * The pkey value that we return to userspace can be different
+		 * from the pkey that caused the fault.
+		 *
+		 * 1. T1   : mprotect_key(foo, PAGE_SIZE, pkey=4);
+		 * 2. T1   : set POR_EL0 to deny access to pkey=4, touches, page
+		 * 3. T1   : faults...
+		 * 4.    T2: mprotect_key(foo, PAGE_SIZE, pkey=5);
+		 * 5. T1   : enters fault handler, takes mmap_lock, etc...
+		 * 6. T1   : reaches here, sees vma_pkey(vma)=5, when we really
+		 *	     faulted on a pte with its pkey=4.
 		 */
-		arm64_force_sig_fault(SIGSEGV,
-				      fault == VM_FAULT_BADACCESS ? SEGV_ACCERR : SEGV_MAPERR,
-				      far, inf->name);
+		/* Something tried to access memory that out of memory map */
+		if (si_code == SEGV_PKUERR)
+			arm64_force_sig_fault_pkey(far, inf->name, pkey);
+		else
+			arm64_force_sig_fault(SIGSEGV, si_code, far, inf->name);
 	}
 
 	return 0;
@@ -684,7 +784,7 @@ no_context:
 }
 
 static int __kprobes do_translation_fault(unsigned long far,
-					  unsigned int esr,
+					  unsigned long esr,
 					  struct pt_regs *regs)
 {
 	unsigned long addr = untagged_addr(far);
@@ -696,19 +796,22 @@ static int __kprobes do_translation_fault(unsigned long far,
 	return 0;
 }
 
-static int do_alignment_fault(unsigned long far, unsigned int esr,
+static int do_alignment_fault(unsigned long far, unsigned long esr,
 			      struct pt_regs *regs)
 {
+	if (IS_ENABLED(CONFIG_COMPAT_ALIGNMENT_FIXUPS) &&
+	    compat_user_mode(regs))
+		return do_compat_alignment_fixup(far, regs);
 	do_bad_area(far, esr, regs);
 	return 0;
 }
 
-static int do_bad(unsigned long far, unsigned int esr, struct pt_regs *regs)
+static int do_bad(unsigned long far, unsigned long esr, struct pt_regs *regs)
 {
 	return 1; /* "fault" */
 }
 
-static int do_sea(unsigned long far, unsigned int esr, struct pt_regs *regs)
+static int do_sea(unsigned long far, unsigned long esr, struct pt_regs *regs)
 {
 	const struct fault_info *inf;
 	unsigned long siaddr;
@@ -733,20 +836,24 @@ static int do_sea(unsigned long far, unsigned int esr, struct pt_regs *regs)
 		 */
 		siaddr  = untagged_addr(far);
 	}
+	add_taint(TAINT_MACHINE_CHECK, LOCKDEP_STILL_OK);
 	arm64_notify_die(inf->name, regs, inf->sig, inf->code, siaddr, esr);
 
 	return 0;
 }
 
-static int do_tag_check_fault(unsigned long far, unsigned int esr,
+static int do_tag_check_fault(unsigned long far, unsigned long esr,
 			      struct pt_regs *regs)
 {
 	/*
 	 * The architecture specifies that bits 63:60 of FAR_EL1 are UNKNOWN
 	 * for tag check faults. Set them to corresponding bits in the untagged
-	 * address.
+	 * address if ARM64_MTE_FAR isn't supported.
+	 * Otherwise, bits 63:60 of FAR_EL1 are not UNKNOWN.
 	 */
-	far = (__untagged_addr(far) & ~MTE_TAG_MASK) | (far & MTE_TAG_MASK);
+	if (!cpus_have_cap(ARM64_MTE_FAR))
+		far = (__untagged_addr(far) & ~MTE_TAG_MASK) | (far & MTE_TAG_MASK);
+
 	do_bad_area(far, esr, regs);
 	return 0;
 }
@@ -760,18 +867,18 @@ static const struct fault_info fault_info[] = {
 	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level 1 translation fault"	},
 	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level 2 translation fault"	},
 	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level 3 translation fault"	},
-	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 8"			},
+	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 0 access flag fault"	},
 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 1 access flag fault"	},
 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 2 access flag fault"	},
 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 3 access flag fault"	},
-	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 12"			},
+	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 0 permission fault"	},
 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 1 permission fault"	},
 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 2 permission fault"	},
 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 3 permission fault"	},
 	{ do_sea,		SIGBUS,  BUS_OBJERR,	"synchronous external abort"	},
 	{ do_tag_check_fault,	SIGSEGV, SEGV_MTESERR,	"synchronous tag check fault"	},
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 18"			},
-	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 19"			},
+	{ do_sea,		SIGKILL, SI_KERNEL,	"level -1 (translation table walk)"	},
 	{ do_sea,		SIGKILL, SI_KERNEL,	"level 0 (translation table walk)"	},
 	{ do_sea,		SIGKILL, SI_KERNEL,	"level 1 (translation table walk)"	},
 	{ do_sea,		SIGKILL, SI_KERNEL,	"level 2 (translation table walk)"	},
@@ -779,7 +886,7 @@ static const struct fault_info fault_info[] = {
 	{ do_sea,		SIGBUS,  BUS_OBJERR,	"synchronous parity or ECC error" },	// Reserved when RAS is implemented
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 25"			},
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 26"			},
-	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 27"			},
+	{ do_sea,		SIGKILL, SI_KERNEL,	"level -1 synchronous parity error (translation table walk)"	},	// Reserved when RAS is implemented
 	{ do_sea,		SIGKILL, SI_KERNEL,	"level 0 synchronous parity error (translation table walk)"	},	// Reserved when RAS is implemented
 	{ do_sea,		SIGKILL, SI_KERNEL,	"level 1 synchronous parity error (translation table walk)"	},	// Reserved when RAS is implemented
 	{ do_sea,		SIGKILL, SI_KERNEL,	"level 2 synchronous parity error (translation table walk)"	},	// Reserved when RAS is implemented
@@ -793,9 +900,9 @@ static const struct fault_info fault_info[] = {
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 38"			},
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 39"			},
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 40"			},
-	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 41"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"level -1 address size fault"	},
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 42"			},
-	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 43"			},
+	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level -1 translation fault"	},
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 44"			},
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 45"			},
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 46"			},
@@ -818,7 +925,7 @@ static const struct fault_info fault_info[] = {
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 63"			},
 };
 
-void do_mem_abort(unsigned long far, unsigned int esr, struct pt_regs *regs)
+void do_mem_abort(unsigned long far, unsigned long esr, struct pt_regs *regs)
 {
 	const struct fault_info *inf = esr_to_fault_info(esr);
 	unsigned long addr = untagged_addr(far);
@@ -826,11 +933,8 @@ void do_mem_abort(unsigned long far, unsigned int esr, struct pt_regs *regs)
 	if (!inf->fn(far, esr, regs))
 		return;
 
-	if (!user_mode(regs)) {
-		pr_alert("Unhandled fault at 0x%016lx\n", addr);
-		mem_abort_decode(esr);
-		show_pte(addr);
-	}
+	if (!user_mode(regs))
+		die_kernel_fault(inf->name, addr, esr, regs);
 
 	/*
 	 * At this point we have an unrecognized fault type whose tag bits may
@@ -841,89 +945,17 @@ void do_mem_abort(unsigned long far, unsigned int esr, struct pt_regs *regs)
 }
 NOKPROBE_SYMBOL(do_mem_abort);
 
-void do_sp_pc_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+void do_sp_pc_abort(unsigned long addr, unsigned long esr, struct pt_regs *regs)
 {
 	arm64_notify_die("SP/PC alignment exception", regs, SIGBUS, BUS_ADRALN,
 			 addr, esr);
 }
 NOKPROBE_SYMBOL(do_sp_pc_abort);
 
-int __init early_brk64(unsigned long addr, unsigned int esr,
-		       struct pt_regs *regs);
-
-/*
- * __refdata because early_brk64 is __init, but the reference to it is
- * clobbered at arch_initcall time.
- * See traps.c and debug-monitors.c:debug_traps_init().
- */
-static struct fault_info __refdata debug_fault_info[] = {
-	{ do_bad,	SIGTRAP,	TRAP_HWBKPT,	"hardware breakpoint"	},
-	{ do_bad,	SIGTRAP,	TRAP_HWBKPT,	"hardware single-step"	},
-	{ do_bad,	SIGTRAP,	TRAP_HWBKPT,	"hardware watchpoint"	},
-	{ do_bad,	SIGKILL,	SI_KERNEL,	"unknown 3"		},
-	{ do_bad,	SIGTRAP,	TRAP_BRKPT,	"aarch32 BKPT"		},
-	{ do_bad,	SIGKILL,	SI_KERNEL,	"aarch32 vector catch"	},
-	{ early_brk64,	SIGTRAP,	TRAP_BRKPT,	"aarch64 BRK"		},
-	{ do_bad,	SIGKILL,	SI_KERNEL,	"unknown 7"		},
-};
-
-void __init hook_debug_fault_code(int nr,
-				  int (*fn)(unsigned long, unsigned int, struct pt_regs *),
-				  int sig, int code, const char *name)
-{
-	BUG_ON(nr < 0 || nr >= ARRAY_SIZE(debug_fault_info));
-
-	debug_fault_info[nr].fn		= fn;
-	debug_fault_info[nr].sig	= sig;
-	debug_fault_info[nr].code	= code;
-	debug_fault_info[nr].name	= name;
-}
-
-/*
- * In debug exception context, we explicitly disable preemption despite
- * having interrupts disabled.
- * This serves two purposes: it makes it much less likely that we would
- * accidentally schedule in exception context and it will force a warning
- * if we somehow manage to schedule by accident.
- */
-static void debug_exception_enter(struct pt_regs *regs)
-{
-	preempt_disable();
-
-	/* This code is a bit fragile.  Test it. */
-	RCU_LOCKDEP_WARN(!rcu_is_watching(), "exception_enter didn't work");
-}
-NOKPROBE_SYMBOL(debug_exception_enter);
-
-static void debug_exception_exit(struct pt_regs *regs)
-{
-	preempt_enable_no_resched();
-}
-NOKPROBE_SYMBOL(debug_exception_exit);
-
-void do_debug_exception(unsigned long addr_if_watchpoint, unsigned int esr,
-			struct pt_regs *regs)
-{
-	const struct fault_info *inf = esr_to_debug_fault_info(esr);
-	unsigned long pc = instruction_pointer(regs);
-
-	debug_exception_enter(regs);
-
-	if (user_mode(regs) && !is_ttbr0_addr(pc))
-		arm64_apply_bp_hardening();
-
-	if (inf->fn(addr_if_watchpoint, esr, regs)) {
-		arm64_notify_die(inf->name, regs, inf->sig, inf->code, pc, esr);
-	}
-
-	debug_exception_exit(regs);
-}
-NOKPROBE_SYMBOL(do_debug_exception);
-
 /*
  * Used during anonymous page fault handling.
  */
-struct page *alloc_zeroed_user_highpage_movable(struct vm_area_struct *vma,
+struct folio *vma_alloc_zeroed_movable_folio(struct vm_area_struct *vma,
 						unsigned long vaddr)
 {
 	gfp_t flags = GFP_HIGHUSER_MOVABLE | __GFP_ZERO;
@@ -936,12 +968,24 @@ struct page *alloc_zeroed_user_highpage_movable(struct vm_area_struct *vma,
 	if (vma->vm_flags & VM_MTE)
 		flags |= __GFP_ZEROTAGS;
 
-	return alloc_page_vma(flags, vma, vaddr);
+	return vma_alloc_folio(flags, 0, vma, vaddr);
 }
 
-void tag_clear_highpage(struct page *page)
+bool tag_clear_highpages(struct page *page, int numpages)
 {
-	mte_zero_clear_page_tags(page_address(page));
-	page_kasan_tag_reset(page);
-	set_bit(PG_mte_tagged, &page->flags);
+	/*
+	 * Check if MTE is supported and fall back to clear_highpage().
+	 * get_huge_zero_folio() unconditionally passes __GFP_ZEROTAGS and
+	 * post_alloc_hook() will invoke tag_clear_highpages().
+	 */
+	if (!system_supports_mte())
+		return false;
+
+	/* Newly allocated pages, shouldn't have been tagged yet */
+	for (int i = 0; i < numpages; i++, page++) {
+		WARN_ON_ONCE(!try_page_mte_tagging(page));
+		mte_zero_clear_page_tags(page_address(page));
+		set_page_mte_tagged(page);
+	}
+	return true;
 }