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

Pull arm64 fixes from Will Deacon:
 "Two arm64 fixes: one fixes a warning that started showing up with
  gcc 16 and the other fixes a lockup in udelay() when running on a
  vCPU loaded on a CPU with the new-fangled WFIT instruction:

   - Fix compiler warning from huge_pte_clear() with GCC 16

   - Fix hang in udelay() on systems with WFIT by consistently using the
     virtual counter to calculate the delta"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: hugetlbpage: avoid unused-but-set-parameter warning (gcc-16)
  arm64: Force the use of CNTVCT_EL0 in __delay()

Author: torvalds

arch/arm64/include/asm/pgtable.h

@@ -144,8 +144,6 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
 	__pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
 
 #define pte_none(pte)		(!pte_val(pte))
-#define __pte_clear(mm, addr, ptep) \
-				__set_pte(ptep, __pte(0))
 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
 
 /*
@@ -1284,6 +1282,13 @@ static inline bool pud_user_accessible_page(pud_t pud, unsigned long addr)
 /*
  * Atomic pte/pmd modifications.
  */
+
+static inline void __pte_clear(struct mm_struct *mm,
+			       unsigned long addr, pte_t *ptep)
+{
+	__set_pte(ptep, __pte(0));
+}
+
 static inline int __ptep_test_and_clear_young(struct vm_area_struct *vma,
 					      unsigned long address,
 					      pte_t *ptep)

arch/arm64/lib/delay.c

@@ -23,9 +23,20 @@ static inline unsigned long xloops_to_cycles(unsigned long xloops)
 	return (xloops * loops_per_jiffy * HZ) >> 32;
 }
 
+/*
+ * Force the use of CNTVCT_EL0 in order to have the same base as WFxT.
+ * This avoids some annoying issues when CNTVOFF_EL2 is not reset 0 on a
+ * KVM host running at EL1 until we do a vcpu_put() on the vcpu. When
+ * running at EL2, the effective offset is always 0.
+ *
+ * Note that userspace cannot change the offset behind our back either,
+ * as the vcpu mutex is held as long as KVM_RUN is in progress.
+ */
+#define __delay_cycles()	__arch_counter_get_cntvct_stable()
+
 void __delay(unsigned long cycles)
 {
-	cycles_t start = get_cycles();
+	cycles_t start = __delay_cycles();
 
 	if (alternative_has_cap_unlikely(ARM64_HAS_WFXT)) {
 		u64 end = start + cycles;
@@ -35,17 +46,17 @@ void __delay(unsigned long cycles)
 		 * early, use a WFET loop to complete the delay.
 		 */
 		wfit(end);
-		while ((get_cycles() - start) < cycles)
+		while ((__delay_cycles() - start) < cycles)
 			wfet(end);
 	} else 	if (arch_timer_evtstrm_available()) {
 		const cycles_t timer_evt_period =
 			USECS_TO_CYCLES(ARCH_TIMER_EVT_STREAM_PERIOD_US);
 
-		while ((get_cycles() - start + timer_evt_period) < cycles)
+		while ((__delay_cycles() - start + timer_evt_period) < cycles)
 			wfe();
 	}
 
-	while ((get_cycles() - start) < cycles)
+	while ((__delay_cycles() - start) < cycles)
 		cpu_relax();
 }
 EXPORT_SYMBOL(__delay);