Merge tag 'x86-urgent-2024-03-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:

 - Ensure that the encryption mask at boot is properly propagated on
   5-level page tables, otherwise the PGD entry is incorrectly set to
   non-encrypted, which causes system crashes during boot.

 - Undo the deferred 5-level page table setup as it cannot work with
   memory encryption enabled.

 - Prevent inconsistent XFD state on CPU hotplug, where the MSR is reset
   to the default value but the cached variable is not, so subsequent
   comparisons might yield the wrong result and as a consequence the
   result prevents updating the MSR.

 - Register the local APIC address only once in the MPPARSE enumeration
   to prevent triggering the related WARN_ONs() in the APIC and topology
   code.

 - Handle the case where no APIC is found gracefully by registering a
   fake APIC in the topology code. That makes all related topology
   functions work correctly and does not affect the actual APIC driver
   code at all.

 - Don't evaluate logical IDs during early boot as the local APIC IDs
   are not yet enumerated and the invoked function returns an error
   code. Nothing requires the logical IDs before the final CPUID
   enumeration takes place, which happens after the enumeration.

 - Cure the fallout of the per CPU rework on UP which misplaced the
   copying of boot_cpu_data to per CPU data so that the final update to
   boot_cpu_data got lost which caused inconsistent state and boot
   crashes.

 - Use copy_from_kernel_nofault() in the kprobes setup as there is no
   guarantee that the address can be safely accessed.

 - Reorder struct members in struct saved_context to work around another
   kmemleak false positive

 - Remove the buggy code which tries to update the E820 kexec table for
   setup_data as that is never passed to the kexec kernel.

 - Update the resource control documentation to use the proper units.

 - Fix a Kconfig warning observed with tinyconfig

* tag 'x86-urgent-2024-03-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/64: Move 5-level paging global variable assignments back
  x86/boot/64: Apply encryption mask to 5-level pagetable update
  x86/cpu: Add model number for another Intel Arrow Lake mobile processor
  x86/fpu: Keep xfd_state in sync with MSR_IA32_XFD
  Documentation/x86: Document that resctrl bandwidth control units are MiB
  x86/mpparse: Register APIC address only once
  x86/topology: Handle the !APIC case gracefully
  x86/topology: Don't evaluate logical IDs during early boot
  x86/cpu: Ensure that CPU info updates are propagated on UP
  kprobes/x86: Use copy_from_kernel_nofault() to read from unsafe address
  x86/pm: Work around false positive kmemleak report in msr_build_context()
  x86/kexec: Do not update E820 kexec table for setup_data
  x86/config: Fix warning for 'make ARCH=x86_64 tinyconfig'

1 files changed, 5 insertions, 27 deletions

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index fe355c89f6c112..76bb65045c649a 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -313,14 +313,6 @@ static void notrace start_secondary(void *unused)
 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
 }
 
-static void __init smp_store_boot_cpu_info(void)
-{
-	struct cpuinfo_x86 *c = &cpu_data(0);
-
-	*c = boot_cpu_data;
-	c->initialized = true;
-}
-
 /*
  * The bootstrap kernel entry code has set these up. Save them for
  * a given CPU
@@ -1039,29 +1031,15 @@ static __init void disable_smp(void)
 	cpumask_set_cpu(0, topology_die_cpumask(0));
 }
 
-static void __init smp_cpu_index_default(void)
-{
-	int i;
-	struct cpuinfo_x86 *c;
-
-	for_each_possible_cpu(i) {
-		c = &cpu_data(i);
-		/* mark all to hotplug */
-		c->cpu_index = nr_cpu_ids;
-	}
-}
-
 void __init smp_prepare_cpus_common(void)
 {
 	unsigned int i;
 
-	smp_cpu_index_default();
-
-	/*
-	 * Setup boot CPU information
-	 */
-	smp_store_boot_cpu_info(); /* Final full version of the data */
-	mb();
+	/* Mark all except the boot CPU as hotpluggable */
+	for_each_possible_cpu(i) {
+		if (i)
+			per_cpu(cpu_info.cpu_index, i) = nr_cpu_ids;
+	}
 
 	for_each_possible_cpu(i) {
 		zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);