Merge tag 'loongarch-fixes-6.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch fixes from Huacai Chen:
 "Fix two cpu-hotplug issues, fix the init sequence about FDT system,
  fix the coding style of dts, and fix the wrong CPUCFG ID handling of
  KVM"

* tag 'loongarch-fixes-6.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  LoongArch: KVM: Streamline kvm_check_cpucfg() and improve comments
  LoongArch: KVM: Rename _kvm_get_cpucfg() to _kvm_get_cpucfg_mask()
  LoongArch: KVM: Fix input validation of _kvm_get_cpucfg() & kvm_check_cpucfg()
  LoongArch: dts: Minor whitespace cleanup
  LoongArch: Call early_init_fdt_scan_reserved_mem() earlier
  LoongArch: Update cpu_sibling_map when disabling nonboot CPUs
  LoongArch: Disable IRQ before init_fn() for nonboot CPUs

Author: torvalds

arch/loongarch/boot/dts/loongson-2k0500-ref.dts

@@ -60,7 +60,7 @@
 
 	#address-cells = <1>;
 	#size-cells = <0>;
-	eeprom@57{
+	eeprom@57 {
 		compatible = "atmel,24c16";
 		reg = <0x57>;
 		pagesize = <16>;

arch/loongarch/boot/dts/loongson-2k1000-ref.dts

@@ -78,7 +78,7 @@
 
 	#address-cells = <1>;
 	#size-cells = <0>;
-	eeprom@57{
+	eeprom@57 {
 		compatible = "atmel,24c16";
 		reg = <0x57>;
 		pagesize = <16>;

arch/loongarch/kernel/setup.c

@@ -357,6 +357,8 @@ void __init platform_init(void)
 	acpi_gbl_use_default_register_widths = false;
 	acpi_boot_table_init();
 #endif
+
+	early_init_fdt_scan_reserved_mem();
 	unflatten_and_copy_device_tree();
 
 #ifdef CONFIG_NUMA
@@ -390,8 +392,6 @@ static void __init arch_mem_init(char **cmdline_p)
 
 	check_kernel_sections_mem();
 
-	early_init_fdt_scan_reserved_mem();
-
 	/*
 	 * In order to reduce the possibility of kernel panic when failed to
 	 * get IO TLB memory under CONFIG_SWIOTLB, it is better to allocate

arch/loongarch/kernel/smp.c

@@ -88,6 +88,73 @@ void show_ipi_list(struct seq_file *p, int prec)
 	}
 }
 
+static inline void set_cpu_core_map(int cpu)
+{
+	int i;
+
+	cpumask_set_cpu(cpu, &cpu_core_setup_map);
+
+	for_each_cpu(i, &cpu_core_setup_map) {
+		if (cpu_data[cpu].package == cpu_data[i].package) {
+			cpumask_set_cpu(i, &cpu_core_map[cpu]);
+			cpumask_set_cpu(cpu, &cpu_core_map[i]);
+		}
+	}
+}
+
+static inline void set_cpu_sibling_map(int cpu)
+{
+	int i;
+
+	cpumask_set_cpu(cpu, &cpu_sibling_setup_map);
+
+	for_each_cpu(i, &cpu_sibling_setup_map) {
+		if (cpus_are_siblings(cpu, i)) {
+			cpumask_set_cpu(i, &cpu_sibling_map[cpu]);
+			cpumask_set_cpu(cpu, &cpu_sibling_map[i]);
+		}
+	}
+}
+
+static inline void clear_cpu_sibling_map(int cpu)
+{
+	int i;
+
+	for_each_cpu(i, &cpu_sibling_setup_map) {
+		if (cpus_are_siblings(cpu, i)) {
+			cpumask_clear_cpu(i, &cpu_sibling_map[cpu]);
+			cpumask_clear_cpu(cpu, &cpu_sibling_map[i]);
+		}
+	}
+
+	cpumask_clear_cpu(cpu, &cpu_sibling_setup_map);
+}
+
+/*
+ * Calculate a new cpu_foreign_map mask whenever a
+ * new cpu appears or disappears.
+ */
+void calculate_cpu_foreign_map(void)
+{
+	int i, k, core_present;
+	cpumask_t temp_foreign_map;
+
+	/* Re-calculate the mask */
+	cpumask_clear(&temp_foreign_map);
+	for_each_online_cpu(i) {
+		core_present = 0;
+		for_each_cpu(k, &temp_foreign_map)
+			if (cpus_are_siblings(i, k))
+				core_present = 1;
+		if (!core_present)
+			cpumask_set_cpu(i, &temp_foreign_map);
+	}
+
+	for_each_online_cpu(i)
+		cpumask_andnot(&cpu_foreign_map[i],
+			       &temp_foreign_map, &cpu_sibling_map[i]);
+}
+
 /* Send mailbox buffer via Mail_Send */
 static void csr_mail_send(uint64_t data, int cpu, int mailbox)
 {
@@ -303,6 +370,7 @@ int loongson_cpu_disable(void)
 	numa_remove_cpu(cpu);
 #endif
 	set_cpu_online(cpu, false);
+	clear_cpu_sibling_map(cpu);
 	calculate_cpu_foreign_map();
 	local_irq_save(flags);
 	irq_migrate_all_off_this_cpu();
@@ -337,6 +405,7 @@ void __noreturn arch_cpu_idle_dead(void)
 		addr = iocsr_read64(LOONGARCH_IOCSR_MBUF0);
 	} while (addr == 0);
 
+	local_irq_disable();
 	init_fn = (void *)TO_CACHE(addr);
 	iocsr_write32(0xffffffff, LOONGARCH_IOCSR_IPI_CLEAR);
 
@@ -379,59 +448,6 @@ static int __init ipi_pm_init(void)
 core_initcall(ipi_pm_init);
 #endif
 
-static inline void set_cpu_sibling_map(int cpu)
-{
-	int i;
-
-	cpumask_set_cpu(cpu, &cpu_sibling_setup_map);
-
-	for_each_cpu(i, &cpu_sibling_setup_map) {
-		if (cpus_are_siblings(cpu, i)) {
-			cpumask_set_cpu(i, &cpu_sibling_map[cpu]);
-			cpumask_set_cpu(cpu, &cpu_sibling_map[i]);
-		}
-	}
-}
-
-static inline void set_cpu_core_map(int cpu)
-{
-	int i;
-
-	cpumask_set_cpu(cpu, &cpu_core_setup_map);
-
-	for_each_cpu(i, &cpu_core_setup_map) {
-		if (cpu_data[cpu].package == cpu_data[i].package) {
-			cpumask_set_cpu(i, &cpu_core_map[cpu]);
-			cpumask_set_cpu(cpu, &cpu_core_map[i]);
-		}
-	}
-}
-
-/*
- * Calculate a new cpu_foreign_map mask whenever a
- * new cpu appears or disappears.
- */
-void calculate_cpu_foreign_map(void)
-{
-	int i, k, core_present;
-	cpumask_t temp_foreign_map;
-
-	/* Re-calculate the mask */
-	cpumask_clear(&temp_foreign_map);
-	for_each_online_cpu(i) {
-		core_present = 0;
-		for_each_cpu(k, &temp_foreign_map)
-			if (cpus_are_siblings(i, k))
-				core_present = 1;
-		if (!core_present)
-			cpumask_set_cpu(i, &temp_foreign_map);
-	}
-
-	for_each_online_cpu(i)
-		cpumask_andnot(&cpu_foreign_map[i],
-			       &temp_foreign_map, &cpu_sibling_map[i]);
-}
-
 /* Preload SMP state for boot cpu */
 void smp_prepare_boot_cpu(void)
 {

arch/loongarch/kvm/vcpu.c

@@ -298,74 +298,73 @@ static int _kvm_setcsr(struct kvm_vcpu *vcpu, unsigned int id, u64 val)
 	return ret;
 }
 
-static int _kvm_get_cpucfg(int id, u64 *v)
+static int _kvm_get_cpucfg_mask(int id, u64 *v)
 {
-	int ret = 0;
-
-	if (id < 0 && id >= KVM_MAX_CPUCFG_REGS)
+	if (id < 0 || id >= KVM_MAX_CPUCFG_REGS)
 		return -EINVAL;
 
 	switch (id) {
 	case 2:
-		/* Return CPUCFG2 features which have been supported by KVM */
+		/* CPUCFG2 features unconditionally supported by KVM */
 		*v = CPUCFG2_FP     | CPUCFG2_FPSP  | CPUCFG2_FPDP     |
 		     CPUCFG2_FPVERS | CPUCFG2_LLFTP | CPUCFG2_LLFTPREV |
 		     CPUCFG2_LAM;
 		/*
-		 * If LSX is supported by CPU, it is also supported by KVM,
-		 * as we implement it.
+		 * For the ISA extensions listed below, if one is supported
+		 * by the host, then it is also supported by KVM.
 		 */
 		if (cpu_has_lsx)
 			*v |= CPUCFG2_LSX;
-		/*
-		 * if LASX is supported by CPU, it is also supported by KVM,
-		 * as we implement it.
-		 */
 		if (cpu_has_lasx)
 			*v |= CPUCFG2_LASX;
 
-		break;
+		return 0;
 	default:
-		ret = -EINVAL;
-		break;
+		/*
+		 * No restrictions on other valid CPUCFG IDs' values, but
+		 * CPUCFG data is limited to 32 bits as the LoongArch ISA
+		 * manual says (Volume 1, Section 2.2.10.5 "CPUCFG").
+		 */
+		*v = U32_MAX;
+		return 0;
 	}
-	return ret;
 }
 
 static int kvm_check_cpucfg(int id, u64 val)
 {
-	u64 mask;
-	int ret = 0;
-
-	if (id < 0 && id >= KVM_MAX_CPUCFG_REGS)
-		return -EINVAL;
+	int ret;
+	u64 mask = 0;
 
-	if (_kvm_get_cpucfg(id, &mask))
+	ret = _kvm_get_cpucfg_mask(id, &mask);
+	if (ret)
 		return ret;
 
+	if (val & ~mask)
+		/* Unsupported features and/or the higher 32 bits should not be set */
+		return -EINVAL;
+
 	switch (id) {
 	case 2:
-		/* CPUCFG2 features checking */
-		if (val & ~mask)
-			/* The unsupported features should not be set */
-			ret = -EINVAL;
-		else if (!(val & CPUCFG2_LLFTP))
-			/* The LLFTP must be set, as guest must has a constant timer */
-			ret = -EINVAL;
-		else if ((val & CPUCFG2_FP) && (!(val & CPUCFG2_FPSP) || !(val & CPUCFG2_FPDP)))
-			/* Single and double float point must both be set when enable FP */
-			ret = -EINVAL;
-		else if ((val & CPUCFG2_LSX) && !(val & CPUCFG2_FP))
-			/* FP should be set when enable LSX */
-			ret = -EINVAL;
-		else if ((val & CPUCFG2_LASX) && !(val & CPUCFG2_LSX))
-			/* LSX, FP should be set when enable LASX, and FP has been checked before. */
-			ret = -EINVAL;
-		break;
+		if (!(val & CPUCFG2_LLFTP))
+			/* Guests must have a constant timer */
+			return -EINVAL;
+		if ((val & CPUCFG2_FP) && (!(val & CPUCFG2_FPSP) || !(val & CPUCFG2_FPDP)))
+			/* Single and double float point must both be set when FP is enabled */
+			return -EINVAL;
+		if ((val & CPUCFG2_LSX) && !(val & CPUCFG2_FP))
+			/* LSX architecturally implies FP but val does not satisfy that */
+			return -EINVAL;
+		if ((val & CPUCFG2_LASX) && !(val & CPUCFG2_LSX))
+			/* LASX architecturally implies LSX and FP but val does not satisfy that */
+			return -EINVAL;
+		return 0;
 	default:
-		break;
+		/*
+		 * Values for the other CPUCFG IDs are not being further validated
+		 * besides the mask check above.
+		 */
+		return 0;
 	}
-	return ret;
 }
 
 static int kvm_get_one_reg(struct kvm_vcpu *vcpu,
@@ -566,7 +565,7 @@ static int kvm_loongarch_get_cpucfg_attr(struct kvm_vcpu *vcpu,
 	uint64_t val;
 	uint64_t __user *uaddr = (uint64_t __user *)attr->addr;
 
-	ret = _kvm_get_cpucfg(attr->attr, &val);
+	ret = _kvm_get_cpucfg_mask(attr->attr, &val);
 	if (ret)
 		return ret;