Merge tag 'x86-cleanups-2023-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull misc x86 cleanups from Ingo Molnar:
 "The following commit deserves special mention:

   22dc02f81cddd Revert "sched/fair: Move unused stub functions to header"

  This is in x86/cleanups, because the revert is a re-application of a
  number of cleanups that got removed inadvertedly"

[ This also effectively undoes the amd_check_microcode() microcode
  declaration change I had done in my microcode loader merge in commit
  42a7f6e3ffe0 ("Merge tag 'x86_microcode_for_v6.6_rc1' [...]").

  I picked the declaration change by Arnd from this branch instead,
  which put it in <asm/processor.h> instead of <asm/microcode.h> like I
  had done in my merge resolution   - Linus ]

* tag 'x86-cleanups-2023-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/platform/uv: Refactor code using deprecated strncpy() interface to use strscpy()
  x86/hpet: Refactor code using deprecated strncpy() interface to use strscpy()
  x86/platform/uv: Refactor code using deprecated strcpy()/strncpy() interfaces to use strscpy()
  x86/qspinlock-paravirt: Fix missing-prototype warning
  x86/paravirt: Silence unused native_pv_lock_init() function warning
  x86/alternative: Add a __alt_reloc_selftest() prototype
  x86/purgatory: Include header for warn() declaration
  x86/asm: Avoid unneeded __div64_32 function definition
  Revert "sched/fair: Move unused stub functions to header"
  x86/apic: Hide unused safe_smp_processor_id() on 32-bit UP
  x86/cpu: Fix amd_check_microcode() declaration

5 files changed, 8 insertions, 5 deletions

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 099d58d02a26..a5ead6a6d233 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -1527,6 +1527,7 @@ static noinline void __init int3_selftest(void)
 
 static __initdata int __alt_reloc_selftest_addr;
 
+extern void __init __alt_reloc_selftest(void *arg);
 __visible noinline void __init __alt_reloc_selftest(void *arg)
 {
 	WARN_ON(arg != &__alt_reloc_selftest_addr);
diff --git a/arch/x86/kernel/apic/ipi.c b/arch/x86/kernel/apic/ipi.c
index 2a6509e8c840..9bfd6e397384 100644
--- a/arch/x86/kernel/apic/ipi.c
+++ b/arch/x86/kernel/apic/ipi.c
@@ -301,6 +301,7 @@ void default_send_IPI_mask_logical(const struct cpumask *cpumask, int vector)
 	local_irq_restore(flags);
 }
 
+#ifdef CONFIG_SMP
 /* must come after the send_IPI functions above for inlining */
 static int convert_apicid_to_cpu(int apic_id)
 {
@@ -329,3 +330,4 @@ int safe_smp_processor_id(void)
 	return cpuid >= 0 ? cpuid : 0;
 }
 #endif
+#endif
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index d9384d5b4b8e..b524dee1cbbb 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -294,8 +294,7 @@ static void __init early_get_apic_socketid_shift(void)
 
 static void __init uv_stringify(int len, char *to, char *from)
 {
-	/* Relies on 'to' being NULL chars so result will be NULL terminated */
-	strncpy(to, from, len-1);
+	strscpy(to, from, len);
 
 	/* Trim trailing spaces */
 	(void)strim(to);
@@ -1013,7 +1012,7 @@ static void __init calc_mmioh_map(enum mmioh_arch index,
 
 	/* One (UV2) mapping */
 	if (index == UV2_MMIOH) {
-		strncpy(id, "MMIOH", sizeof(id));
+		strscpy(id, "MMIOH", sizeof(id));
 		max_io = max_pnode;
 		mapped = 0;
 		goto map_exit;
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index c8eb1ac5125a..1648aa0204d9 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -421,7 +421,7 @@ static void __init hpet_legacy_clockevent_register(struct hpet_channel *hc)
 	 * the IO_APIC has been initialized.
 	 */
 	hc->cpu = boot_cpu_data.cpu_index;
-	strncpy(hc->name, "hpet", sizeof(hc->name));
+	strscpy(hc->name, "hpet", sizeof(hc->name));
 	hpet_init_clockevent(hc, 50);
 
 	hc->evt.tick_resume	= hpet_clkevt_legacy_resume;
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 23d4d7114473..975f98d5eee5 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -75,7 +75,8 @@ DEFINE_STATIC_KEY_TRUE(virt_spin_lock_key);
 
 void __init native_pv_lock_init(void)
 {
-	if (!boot_cpu_has(X86_FEATURE_HYPERVISOR))
+	if (IS_ENABLED(CONFIG_PARAVIRT_SPINLOCKS) &&
+	    !boot_cpu_has(X86_FEATURE_HYPERVISOR))
 		static_branch_disable(&virt_spin_lock_key);
 }