Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:
 "There's a reasonable amount here and the juicy details are all below.

  It's worth noting that the MTE/KASAN changes strayed outside of our
  usual directories due to core mm changes and some associated changes
  to some other architectures; Andrew asked for us to carry these [1]
  rather that take them via the -mm tree.

  Summary:

   - Optimise SVE switching for CPUs with 128-bit implementations.

   - Fix output format from SVE selftest.

   - Add support for versions v1.2 and 1.3 of the SMC calling
     convention.

   - Allow Pointer Authentication to be configured independently for
     kernel and userspace.

   - PMU driver cleanups for managing IRQ affinity and exposing event
     attributes via sysfs.

   - KASAN optimisations for both hardware tagging (MTE) and out-of-line
     software tagging implementations.

   - Relax frame record alignment requirements to facilitate 8-byte
     alignment with KASAN and Clang.

   - Cleanup of page-table definitions and removal of unused memory
     types.

   - Reduction of ARCH_DMA_MINALIGN back to 64 bytes.

   - Refactoring of our instruction decoding routines and addition of
     some missing encodings.

   - Move entry code moved into C and hardened against harmful compiler
     instrumentation.

   - Update booting requirements for the FEAT_HCX feature, added to v8.7
     of the architecture.

   - Fix resume from idle when pNMI is being used.

   - Additional CPU sanity checks for MTE and preparatory changes for
     systems where not all of the CPUs support 32-bit EL0.

   - Update our kernel string routines to the latest Cortex Strings
     implementation.

   - Big cleanup of our cache maintenance routines, which were
     confusingly named and inconsistent in their implementations.

   - Tweak linker flags so that GDB can understand vmlinux when using
     RELR relocations.

   - Boot path cleanups to enable early initialisation of per-cpu
     operations needed by KCSAN.

   - Non-critical fixes and miscellaneous cleanup"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (150 commits)
  arm64: tlb: fix the TTL value of tlb_get_level
  arm64: Restrict undef hook for cpufeature registers
  arm64/mm: Rename ARM64_SWAPPER_USES_SECTION_MAPS
  arm64: insn: avoid circular include dependency
  arm64: smp: Bump debugging information print down to KERN_DEBUG
  drivers/perf: fix the missed ida_simple_remove() in ddr_perf_probe()
  perf/arm-cmn: Fix invalid pointer when access dtc object sharing the same IRQ number
  arm64: suspend: Use cpuidle context helpers in cpu_suspend()
  PSCI: Use cpuidle context helpers in psci_cpu_suspend_enter()
  arm64: Convert cpu_do_idle() to using cpuidle context helpers
  arm64: Add cpuidle context save/restore helpers
  arm64: head: fix code comments in set_cpu_boot_mode_flag
  arm64: mm: drop unused __pa(__idmap_text_start)
  arm64: mm: fix the count comments in compute_indices
  arm64/mm: Fix ttbr0 values stored in struct thread_info for software-pan
  arm64: mm: Pass original fault address to handle_mm_fault()
  arm64/mm: Drop SECTION_[SHIFT|SIZE|MASK]
  arm64/mm: Use CONT_PMD_SHIFT for ARM64_MEMSTART_SHIFT
  arm64/mm: Drop SWAPPER_INIT_MAP_SIZE
  arm64: Conditionally configure PTR_AUTH key of the kernel.
  ...

arch/arm64/kernel/smp.c

@@ -120,9 +120,7 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle)
 	 * page tables.
 	 */
 	secondary_data.task = idle;
-	secondary_data.stack = task_stack_page(idle) + THREAD_SIZE;
 	update_cpu_boot_status(CPU_MMU_OFF);
-	__flush_dcache_area(&secondary_data, sizeof(secondary_data));
 
 	/* Now bring the CPU into our world */
 	ret = boot_secondary(cpu, idle);
@@ -142,8 +140,6 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle)
 
 	pr_crit("CPU%u: failed to come online\n", cpu);
 	secondary_data.task = NULL;
-	secondary_data.stack = NULL;
-	__flush_dcache_area(&secondary_data, sizeof(secondary_data));
 	status = READ_ONCE(secondary_data.status);
 	if (status == CPU_MMU_OFF)
 		status = READ_ONCE(__early_cpu_boot_status);
@@ -202,10 +198,7 @@ asmlinkage notrace void secondary_start_kernel(void)
 	u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
 	struct mm_struct *mm = &init_mm;
 	const struct cpu_operations *ops;
-	unsigned int cpu;
-
-	cpu = task_cpu(current);
-	set_my_cpu_offset(per_cpu_offset(cpu));
+	unsigned int cpu = smp_processor_id();
 
 	/*
 	 * All kernel threads share the same mm context; grab a
@@ -351,7 +344,7 @@ void __cpu_die(unsigned int cpu)
 		pr_crit("CPU%u: cpu didn't die\n", cpu);
 		return;
 	}
-	pr_notice("CPU%u: shutdown\n", cpu);
+	pr_debug("CPU%u: shutdown\n", cpu);
 
 	/*
 	 * Now that the dying CPU is beyond the point of no return w.r.t.
@@ -451,6 +444,11 @@ void __init smp_cpus_done(unsigned int max_cpus)
 
 void __init smp_prepare_boot_cpu(void)
 {
+	/*
+	 * The runtime per-cpu areas have been allocated by
+	 * setup_per_cpu_areas(), and CPU0's boot time per-cpu area will be
+	 * freed shortly, so we must move over to the runtime per-cpu area.
+	 */
 	set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
 	cpuinfo_store_boot_cpu();