LoongArch fixes for v6.17-rc7

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Merge tag 'loongarch-fixes-6.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch fixes from Huacai Chen:
 "Fix some build warnings for RUST-enabled objtool check, align ACPI
  structures for ARCH_STRICT_ALIGN, fix an unreliable stack for live
  patching, add some NULL pointer checkings, and fix some bugs around
  KVM"

* tag 'loongarch-fixes-6.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  LoongArch: KVM: Avoid copy_*_user() with lock hold in kvm_pch_pic_regs_access()
  LoongArch: KVM: Avoid copy_*_user() with lock hold in kvm_eiointc_sw_status_access()
  LoongArch: KVM: Avoid copy_*_user() with lock hold in kvm_eiointc_regs_access()
  LoongArch: KVM: Avoid copy_*_user() with lock hold in kvm_eiointc_ctrl_access()
  LoongArch: KVM: Fix VM migration failure with PTW enabled
  LoongArch: KVM: Remove unused returns and semicolons
  LoongArch: vDSO: Check kcalloc() result in init_vdso()
  LoongArch: Fix unreliable stack for live patching
  LoongArch: Replace sprintf() with sysfs_emit()
  LoongArch: Check the return value when creating kobj
  LoongArch: Align ACPI structures if ARCH_STRICT_ALIGN enabled
  LoongArch: Update help info of ARCH_STRICT_ALIGN
  LoongArch: Handle jump tables options for RUST
  LoongArch: Make LTO case independent in Makefile
  objtool/LoongArch: Mark special atomic instruction as INSN_BUG type
  objtool/LoongArch: Mark types based on break immediate code

arch/loongarch/Kconfig

@@ -298,6 +298,10 @@ config AS_HAS_LVZ_EXTENSION
 config CC_HAS_ANNOTATE_TABLEJUMP
 	def_bool $(cc-option,-mannotate-tablejump)
 
+config RUSTC_HAS_ANNOTATE_TABLEJUMP
+	depends on RUST
+	def_bool $(rustc-option,-Cllvm-args=--loongarch-annotate-tablejump)
+
 menu "Kernel type and options"
 
 source "kernel/Kconfig.hz"
@@ -563,10 +567,14 @@ config ARCH_STRICT_ALIGN
 	  -mstrict-align build parameter to prevent unaligned accesses.
 
 	  CPUs with h/w unaligned access support:
-	  Loongson-2K2000/2K3000/3A5000/3C5000/3D5000.
+	  Loongson-2K2000/2K3000 and all of Loongson-3 series processors
+	  based on LoongArch.
 
 	  CPUs without h/w unaligned access support:
-	  Loongson-2K500/2K1000.
+	  Loongson-2K0300/2K0500/2K1000.
+
+	  If you want to make sure whether to support unaligned memory access
+	  on your hardware, please read the bit 20 (UAL) of CPUCFG1 register.
 
 	  This option is enabled by default to make the kernel be able to run
 	  on all LoongArch systems. But you can disable it manually if you want

arch/loongarch/Makefile

@@ -102,16 +102,21 @@ KBUILD_CFLAGS			+= $(call cc-option,-mthin-add-sub) $(call cc-option,-Wa$(comma)
 
 ifdef CONFIG_OBJTOOL
 ifdef CONFIG_CC_HAS_ANNOTATE_TABLEJUMP
+KBUILD_CFLAGS			+= -mannotate-tablejump
+else
+KBUILD_CFLAGS			+= -fno-jump-tables # keep compatibility with older compilers
+endif
+ifdef CONFIG_RUSTC_HAS_ANNOTATE_TABLEJUMP
+KBUILD_RUSTFLAGS		+= -Cllvm-args=--loongarch-annotate-tablejump
+else
+KBUILD_RUSTFLAGS		+= -Zno-jump-tables # keep compatibility with older compilers
+endif
+ifdef CONFIG_LTO_CLANG
 # The annotate-tablejump option can not be passed to LLVM backend when LTO is enabled.
 # Ensure it is aware of linker with LTO, '--loongarch-annotate-tablejump' also needs to
 # be passed via '-mllvm' to ld.lld.
-KBUILD_CFLAGS			+= -mannotate-tablejump
-ifdef CONFIG_LTO_CLANG
 KBUILD_LDFLAGS			+= -mllvm --loongarch-annotate-tablejump
 endif
-else
-KBUILD_CFLAGS			+= -fno-jump-tables # keep compatibility with older compilers
-endif
 endif
 
 KBUILD_RUSTFLAGS		+= --target=loongarch64-unknown-none-softfloat -Ccode-model=small

arch/loongarch/include/asm/acenv.h

@@ -10,9 +10,8 @@
 #ifndef _ASM_LOONGARCH_ACENV_H
 #define _ASM_LOONGARCH_ACENV_H
 
-/*
+#ifdef CONFIG_ARCH_STRICT_ALIGN
- * This header is required by ACPI core, but we have nothing to fill in
+#define ACPI_MISALIGNMENT_NOT_SUPPORTED
- * right now. Will be updated later when needed.
+#endif /* CONFIG_ARCH_STRICT_ALIGN */
- */
 
 #endif /* _ASM_LOONGARCH_ACENV_H */

arch/loongarch/include/asm/kvm_mmu.h

@@ -16,6 +16,13 @@
  */
 #define KVM_MMU_CACHE_MIN_PAGES	(CONFIG_PGTABLE_LEVELS - 1)
 
+/*
+ * _PAGE_MODIFIED is a SW pte bit, it records page ever written on host
+ * kernel, on secondary MMU it records the page writeable attribute, in
+ * order for fast path handling.
+ */
+#define KVM_PAGE_WRITEABLE	_PAGE_MODIFIED
+
 #define _KVM_FLUSH_PGTABLE	0x1
 #define _KVM_HAS_PGMASK		0x2
 #define kvm_pfn_pte(pfn, prot)	(((pfn) << PFN_PTE_SHIFT) | pgprot_val(prot))
@@ -52,10 +59,10 @@ static inline void kvm_set_pte(kvm_pte_t *ptep, kvm_pte_t val)
 	WRITE_ONCE(*ptep, val);
 }
 
-static inline int kvm_pte_write(kvm_pte_t pte) { return pte & _PAGE_WRITE; }
-static inline int kvm_pte_dirty(kvm_pte_t pte) { return pte & _PAGE_DIRTY; }
 static inline int kvm_pte_young(kvm_pte_t pte) { return pte & _PAGE_ACCESSED; }
 static inline int kvm_pte_huge(kvm_pte_t pte) { return pte & _PAGE_HUGE; }
+static inline int kvm_pte_dirty(kvm_pte_t pte) { return pte & __WRITEABLE; }
+static inline int kvm_pte_writeable(kvm_pte_t pte) { return pte & KVM_PAGE_WRITEABLE; }
 
 static inline kvm_pte_t kvm_pte_mkyoung(kvm_pte_t pte)
 {
@@ -69,12 +76,12 @@ static inline kvm_pte_t kvm_pte_mkold(kvm_pte_t pte)
 
 static inline kvm_pte_t kvm_pte_mkdirty(kvm_pte_t pte)
 {
-	return pte | _PAGE_DIRTY;
+	return pte | __WRITEABLE;
 }
 
 static inline kvm_pte_t kvm_pte_mkclean(kvm_pte_t pte)
 {
-	return pte & ~_PAGE_DIRTY;
+	return pte & ~__WRITEABLE;
 }
 
 static inline kvm_pte_t kvm_pte_mkhuge(kvm_pte_t pte)
@@ -87,6 +94,11 @@ static inline kvm_pte_t kvm_pte_mksmall(kvm_pte_t pte)
 	return pte & ~_PAGE_HUGE;
 }
 
+static inline kvm_pte_t kvm_pte_mkwriteable(kvm_pte_t pte)
+{
+	return pte | KVM_PAGE_WRITEABLE;
+}
+
 static inline int kvm_need_flush(kvm_ptw_ctx *ctx)
 {
 	return ctx->flag & _KVM_FLUSH_PGTABLE;

arch/loongarch/kernel/env.c

@@ -86,7 +86,7 @@ late_initcall(fdt_cpu_clk_init);
 static ssize_t boardinfo_show(struct kobject *kobj,
 			      struct kobj_attribute *attr, char *buf)
 {
-	return sprintf(buf,
+	return sysfs_emit(buf,
 		"BIOS Information\n"
 		"Vendor\t\t\t: %s\n"
 		"Version\t\t\t: %s\n"
@@ -109,6 +109,8 @@ static int __init boardinfo_init(void)
 	struct kobject *loongson_kobj;
 
 	loongson_kobj = kobject_create_and_add("loongson", firmware_kobj);
+	if (!loongson_kobj)
+		return -ENOMEM;
 
 	return sysfs_create_file(loongson_kobj, &boardinfo_attr.attr);
 }

arch/loongarch/kernel/stacktrace.c

@@ -51,12 +51,13 @@ int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry,
 	if (task == current) {
 		regs->regs[3] = (unsigned long)__builtin_frame_address(0);
 		regs->csr_era = (unsigned long)__builtin_return_address(0);
+		regs->regs[22] = 0;
 	} else {
 		regs->regs[3] = thread_saved_fp(task);
 		regs->csr_era = thread_saved_ra(task);
+		regs->regs[22] = task->thread.reg22;
 	}
 	regs->regs[1] = 0;
-	regs->regs[22] = 0;
 
 	for (unwind_start(&state, task, regs);
 	     !unwind_done(&state) && !unwind_error(&state); unwind_next_frame(&state)) {

arch/loongarch/kernel/vdso.c

@@ -54,6 +54,9 @@ static int __init init_vdso(void)
 	vdso_info.code_mapping.pages =
 		kcalloc(vdso_info.size / PAGE_SIZE, sizeof(struct page *), GFP_KERNEL);
 
+	if (!vdso_info.code_mapping.pages)
+		return -ENOMEM;
+
 	pfn = __phys_to_pfn(__pa_symbol(vdso_info.vdso));
 	for (i = 0; i < vdso_info.size / PAGE_SIZE; i++)
 		vdso_info.code_mapping.pages[i] = pfn_to_page(pfn + i);

arch/loongarch/kvm/exit.c

@@ -778,10 +778,8 @@ static long kvm_save_notify(struct kvm_vcpu *vcpu)
 		return 0;
 	default:
 		return KVM_HCALL_INVALID_CODE;
-	};
+	}
-
+}
-	return KVM_HCALL_INVALID_CODE;
-};
 
 /*
  * kvm_handle_lsx_disabled() - Guest used LSX while disabled in root.

arch/loongarch/kvm/intc/eiointc.c

@@ -426,21 +426,26 @@ static int kvm_eiointc_ctrl_access(struct kvm_device *dev,
 	struct loongarch_eiointc *s = dev->kvm->arch.eiointc;
 
 	data = (void __user *)attr->addr;
+	switch (type) {
+	case KVM_DEV_LOONGARCH_EXTIOI_CTRL_INIT_NUM_CPU:
+	case KVM_DEV_LOONGARCH_EXTIOI_CTRL_INIT_FEATURE:
+		if (copy_from_user(&val, data, 4))
+			return -EFAULT;
+		break;
+	default:
+		break;
+	}
+
 	spin_lock_irqsave(&s->lock, flags);
 	switch (type) {
 	case KVM_DEV_LOONGARCH_EXTIOI_CTRL_INIT_NUM_CPU:
-		if (copy_from_user(&val, data, 4))
+		if (val >= EIOINTC_ROUTE_MAX_VCPUS)
-			ret = -EFAULT;
+			ret = -EINVAL;
-		else {
+		else
-			if (val >= EIOINTC_ROUTE_MAX_VCPUS)
+			s->num_cpu = val;
-				ret = -EINVAL;
-			else
-				s->num_cpu = val;
-		}
 		break;
 	case KVM_DEV_LOONGARCH_EXTIOI_CTRL_INIT_FEATURE:
-		if (copy_from_user(&s->features, data, 4))
+		s->features = val;
-			ret = -EFAULT;
 		if (!(s->features & BIT(EIOINTC_HAS_VIRT_EXTENSION)))
 			s->status |= BIT(EIOINTC_ENABLE);
 		break;
@@ -462,19 +467,17 @@ static int kvm_eiointc_ctrl_access(struct kvm_device *dev,
 
 static int kvm_eiointc_regs_access(struct kvm_device *dev,
 					struct kvm_device_attr *attr,
-					bool is_write)
+					bool is_write, int *data)
 {
 	int addr, cpu, offset, ret = 0;
 	unsigned long flags;
 	void *p = NULL;
-	void __user *data;
 	struct loongarch_eiointc *s;
 
 	s = dev->kvm->arch.eiointc;
 	addr = attr->attr;
 	cpu = addr >> 16;
 	addr &= 0xffff;
-	data = (void __user *)attr->addr;
 	switch (addr) {
 	case EIOINTC_NODETYPE_START ... EIOINTC_NODETYPE_END:
 		offset = (addr - EIOINTC_NODETYPE_START) / 4;
@@ -513,13 +516,10 @@ static int kvm_eiointc_regs_access(struct kvm_device *dev,
 	}
 
 	spin_lock_irqsave(&s->lock, flags);
-	if (is_write) {
+	if (is_write)
-		if (copy_from_user(p, data, 4))
+		memcpy(p, data, 4);
-			ret = -EFAULT;
+	else
-	} else {
+		memcpy(data, p, 4);
-		if (copy_to_user(data, p, 4))
-			ret = -EFAULT;
-	}
 	spin_unlock_irqrestore(&s->lock, flags);
 
 	return ret;
@@ -527,19 +527,17 @@ static int kvm_eiointc_regs_access(struct kvm_device *dev,
 
 static int kvm_eiointc_sw_status_access(struct kvm_device *dev,
 					struct kvm_device_attr *attr,
-					bool is_write)
+					bool is_write, int *data)
 {
 	int addr, ret = 0;
 	unsigned long flags;
 	void *p = NULL;
-	void __user *data;
 	struct loongarch_eiointc *s;
 
 	s = dev->kvm->arch.eiointc;
 	addr = attr->attr;
 	addr &= 0xffff;
 
-	data = (void __user *)attr->addr;
 	switch (addr) {
 	case KVM_DEV_LOONGARCH_EXTIOI_SW_STATUS_NUM_CPU:
 		if (is_write)
@@ -561,13 +559,10 @@ static int kvm_eiointc_sw_status_access(struct kvm_device *dev,
 		return -EINVAL;
 	}
 	spin_lock_irqsave(&s->lock, flags);
-	if (is_write) {
+	if (is_write)
-		if (copy_from_user(p, data, 4))
+		memcpy(p, data, 4);
-			ret = -EFAULT;
+	else
-	} else {
+		memcpy(data, p, 4);
-		if (copy_to_user(data, p, 4))
-			ret = -EFAULT;
-	}
 	spin_unlock_irqrestore(&s->lock, flags);
 
 	return ret;
@@ -576,11 +571,27 @@ static int kvm_eiointc_sw_status_access(struct kvm_device *dev,
 static int kvm_eiointc_get_attr(struct kvm_device *dev,
 				struct kvm_device_attr *attr)
 {
+	int ret, data;
+
 	switch (attr->group) {
 	case KVM_DEV_LOONGARCH_EXTIOI_GRP_REGS:
-		return kvm_eiointc_regs_access(dev, attr, false);
+		ret = kvm_eiointc_regs_access(dev, attr, false, &data);
+		if (ret)
+			return ret;
+
+		if (copy_to_user((void __user *)attr->addr, &data, 4))
+			ret = -EFAULT;
+
+		return ret;
 	case KVM_DEV_LOONGARCH_EXTIOI_GRP_SW_STATUS:
-		return kvm_eiointc_sw_status_access(dev, attr, false);
+		ret = kvm_eiointc_sw_status_access(dev, attr, false, &data);
+		if (ret)
+			return ret;
+
+		if (copy_to_user((void __user *)attr->addr, &data, 4))
+			ret = -EFAULT;
+
+		return ret;
 	default:
 		return -EINVAL;
 	}
@@ -589,13 +600,21 @@ static int kvm_eiointc_get_attr(struct kvm_device *dev,
 static int kvm_eiointc_set_attr(struct kvm_device *dev,
 				struct kvm_device_attr *attr)
 {
+	int data;
+
 	switch (attr->group) {
 	case KVM_DEV_LOONGARCH_EXTIOI_GRP_CTRL:
 		return kvm_eiointc_ctrl_access(dev, attr);
 	case KVM_DEV_LOONGARCH_EXTIOI_GRP_REGS:
-		return kvm_eiointc_regs_access(dev, attr, true);
+		if (copy_from_user(&data, (void __user *)attr->addr, 4))
+			return -EFAULT;
+
+		return kvm_eiointc_regs_access(dev, attr, true, &data);
 	case KVM_DEV_LOONGARCH_EXTIOI_GRP_SW_STATUS:
-		return kvm_eiointc_sw_status_access(dev, attr, true);
+		if (copy_from_user(&data, (void __user *)attr->addr, 4))
+			return -EFAULT;
+
+		return kvm_eiointc_sw_status_access(dev, attr, true, &data);
 	default:
 		return -EINVAL;
 	}

arch/loongarch/kvm/intc/pch_pic.c

@@ -348,6 +348,7 @@ static int kvm_pch_pic_regs_access(struct kvm_device *dev,
 				struct kvm_device_attr *attr,
 				bool is_write)
 {
+	char buf[8];
 	int addr, offset, len = 8, ret = 0;
 	void __user *data;
 	void *p = NULL;
@@ -397,17 +398,23 @@ static int kvm_pch_pic_regs_access(struct kvm_device *dev,
 		return -EINVAL;
 	}
 
-	spin_lock(&s->lock);
-	/* write or read value according to is_write */
 	if (is_write) {
-		if (copy_from_user(p, data, len))
+		if (copy_from_user(buf, data, len))
-			ret = -EFAULT;
+			return -EFAULT;
-	} else {
-		if (copy_to_user(data, p, len))
-			ret = -EFAULT;
 	}
+
+	spin_lock(&s->lock);
+	if (is_write)
+		memcpy(p, buf, len);
+	else
+		memcpy(buf, p, len);
 	spin_unlock(&s->lock);
 
+	if (!is_write) {
+		if (copy_to_user(data, buf, len))
+			return -EFAULT;
+	}
+
 	return ret;
 }
 

arch/loongarch/kvm/mmu.c

@@ -569,7 +569,7 @@ static int kvm_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa, bool writ
 	/* Track access to pages marked old */
 	new = kvm_pte_mkyoung(*ptep);
 	if (write && !kvm_pte_dirty(new)) {
-		if (!kvm_pte_write(new)) {
+		if (!kvm_pte_writeable(new)) {
 			ret = -EFAULT;
 			goto out;
 		}
@@ -856,9 +856,9 @@ static int kvm_map_page(struct kvm_vcpu *vcpu, unsigned long gpa, bool write)
 		prot_bits |= _CACHE_SUC;
 
 	if (writeable) {
-		prot_bits |= _PAGE_WRITE;
+		prot_bits = kvm_pte_mkwriteable(prot_bits);
 		if (write)
-			prot_bits |= __WRITEABLE;
+			prot_bits = kvm_pte_mkdirty(prot_bits);
 	}
 
 	/* Disable dirty logging on HugePages */
@@ -904,7 +904,7 @@ static int kvm_map_page(struct kvm_vcpu *vcpu, unsigned long gpa, bool write)
 	kvm_release_faultin_page(kvm, page, false, writeable);
 	spin_unlock(&kvm->mmu_lock);
 
-	if (prot_bits & _PAGE_DIRTY)
+	if (kvm_pte_dirty(prot_bits))
 		mark_page_dirty_in_slot(kvm, memslot, gfn);
 
 out:

tools/arch/loongarch/include/asm/inst.h

@@ -51,6 +51,10 @@ enum reg2i16_op {
 	bgeu_op		= 0x1b,
 };
 
+enum reg3_op {
+	amswapw_op	= 0x70c0,
+};
+
 struct reg0i15_format {
 	unsigned int immediate : 15;
 	unsigned int opcode : 17;
@@ -96,6 +100,13 @@ struct reg2i16_format {
 	unsigned int opcode : 6;
 };
 
+struct reg3_format {
+	unsigned int rd : 5;
+	unsigned int rj : 5;
+	unsigned int rk : 5;
+	unsigned int opcode : 17;
+};
+
 union loongarch_instruction {
 	unsigned int word;
 	struct reg0i15_format	reg0i15_format;
@@ -105,6 +116,7 @@ union loongarch_instruction {
 	struct reg2i12_format	reg2i12_format;
 	struct reg2i14_format	reg2i14_format;
 	struct reg2i16_format	reg2i16_format;
+	struct reg3_format	reg3_format;
 };
 
 #define LOONGARCH_INSN_SIZE	sizeof(union loongarch_instruction)

tools/objtool/arch/loongarch/decode.c

@@ -278,6 +278,25 @@ static bool decode_insn_reg2i16_fomat(union loongarch_instruction inst,
 	return true;
 }
 
+static bool decode_insn_reg3_fomat(union loongarch_instruction inst,
+				   struct instruction *insn)
+{
+	switch (inst.reg3_format.opcode) {
+	case amswapw_op:
+		if (inst.reg3_format.rd == LOONGARCH_GPR_ZERO &&
+		    inst.reg3_format.rk == LOONGARCH_GPR_RA &&
+		    inst.reg3_format.rj == LOONGARCH_GPR_ZERO) {
+			/* amswap.w $zero, $ra, $zero */
+			insn->type = INSN_BUG;
+		}
+		break;
+	default:
+		return false;
+	}
+
+	return true;
+}
+
 int arch_decode_instruction(struct objtool_file *file, const struct section *sec,
 			    unsigned long offset, unsigned int maxlen,
 			    struct instruction *insn)
@@ -309,11 +328,19 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec
 		return 0;
 	if (decode_insn_reg2i16_fomat(inst, insn))
 		return 0;
+	if (decode_insn_reg3_fomat(inst, insn))
+		return 0;
 
-	if (inst.word == 0)
+	if (inst.word == 0) {
+		/* andi $zero, $zero, 0x0 */
 		insn->type = INSN_NOP;
-	else if (inst.reg0i15_format.opcode == break_op) {
+	} else if (inst.reg0i15_format.opcode == break_op &&
-		/* break */
+		   inst.reg0i15_format.immediate == 0x0) {
+		/* break 0x0 */
+		insn->type = INSN_TRAP;
+	} else if (inst.reg0i15_format.opcode == break_op &&
+		   inst.reg0i15_format.immediate == 0x1) {
+		/* break 0x1 */
 		insn->type = INSN_BUG;
 	} else if (inst.reg2_format.opcode == ertn_op) {
 		/* ertn */