17 files changed, 597 insertions, 41 deletions

diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile
index 6f5a4574a911..001924877772 100644
--- a/arch/loongarch/kernel/Makefile
+++ b/arch/loongarch/kernel/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_MAGIC_SYSRQ)	+= sysrq.o
 obj-$(CONFIG_RELOCATABLE)	+= relocate.o
 
 obj-$(CONFIG_KEXEC_CORE)	+= machine_kexec.o relocate_kernel.o
+obj-$(CONFIG_KEXEC_FILE)	+= machine_kexec_file.o kexec_efi.o kexec_elf.o
 obj-$(CONFIG_CRASH_DUMP)	+= crash_dump.o
 
 obj-$(CONFIG_UNWINDER_GUESS)	+= unwind_guess.o
diff --git a/arch/loongarch/kernel/asm-offsets.c b/arch/loongarch/kernel/asm-offsets.c
index db1e4bb26b6a..3017c7157600 100644
--- a/arch/loongarch/kernel/asm-offsets.c
+++ b/arch/loongarch/kernel/asm-offsets.c
@@ -4,6 +4,8 @@
  *
  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
  */
+#define COMPILE_OFFSETS
+
 #include <linux/types.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
diff --git a/arch/loongarch/kernel/cpu-probe.c b/arch/loongarch/kernel/cpu-probe.c
index fedaa67cde41..cbfce2872d71 100644
--- a/arch/loongarch/kernel/cpu-probe.c
+++ b/arch/loongarch/kernel/cpu-probe.c
@@ -52,6 +52,48 @@ static inline void cpu_set_fpu_fcsr_mask(struct cpuinfo_loongarch *c)
 	c->fpu_mask = ~(fcsr0 ^ fcsr1) & ~mask;
 }
 
+/* simd = -1/0/128/256 */
+static unsigned int simd = -1U;
+
+static int __init cpu_setup_simd(char *str)
+{
+	get_option(&str, &simd);
+	pr_info("Set SIMD width = %u\n", simd);
+
+	return 0;
+}
+
+early_param("simd", cpu_setup_simd);
+
+static int __init cpu_final_simd(void)
+{
+	struct cpuinfo_loongarch *c = &cpu_data[0];
+
+	if (simd < 128) {
+		c->options &= ~LOONGARCH_CPU_LSX;
+		elf_hwcap &= ~HWCAP_LOONGARCH_LSX;
+	}
+
+	if (simd < 256) {
+		c->options &= ~LOONGARCH_CPU_LASX;
+		elf_hwcap &= ~HWCAP_LOONGARCH_LASX;
+	}
+
+	simd = 0;
+
+	if (c->options & LOONGARCH_CPU_LSX)
+		simd = 128;
+
+	if (c->options & LOONGARCH_CPU_LASX)
+		simd = 256;
+
+	pr_info("Final SIMD width = %u\n", simd);
+
+	return 0;
+}
+
+arch_initcall(cpu_final_simd);
+
 static inline void set_elf_platform(int cpu, const char *plat)
 {
 	if (cpu == 0)
@@ -134,13 +176,13 @@ static void cpu_probe_common(struct cpuinfo_loongarch *c)
 		elf_hwcap |= HWCAP_LOONGARCH_FPU;
 	}
 #ifdef CONFIG_CPU_HAS_LSX
-	if (config & CPUCFG2_LSX) {
+	if ((config & CPUCFG2_LSX) && (simd >= 128)) {
 		c->options |= LOONGARCH_CPU_LSX;
 		elf_hwcap |= HWCAP_LOONGARCH_LSX;
 	}
 #endif
 #ifdef CONFIG_CPU_HAS_LASX
-	if (config & CPUCFG2_LASX) {
+	if ((config & CPUCFG2_LASX) && (simd >= 256)) {
 		c->options |= LOONGARCH_CPU_LASX;
 		elf_hwcap |= HWCAP_LOONGARCH_LASX;
 	}
diff --git a/arch/loongarch/kernel/env.c b/arch/loongarch/kernel/env.c
index c0a5dc9aeae2..23bd5ae2212c 100644
--- a/arch/loongarch/kernel/env.c
+++ b/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);
 }
diff --git a/arch/loongarch/kernel/inst.c b/arch/loongarch/kernel/inst.c
index 72ecfed29d55..bf037f0c6b26 100644
--- a/arch/loongarch/kernel/inst.c
+++ b/arch/loongarch/kernel/inst.c
@@ -141,6 +141,9 @@ bool insns_not_supported(union loongarch_instruction insn)
 	case amswapw_op ... ammindbdu_op:
 		pr_notice("atomic memory access instructions are not supported\n");
 		return true;
+	case scq_op:
+		pr_notice("sc.q instruction is not supported\n");
+		return true;
 	}
 
 	switch (insn.reg2i14_format.opcode) {
@@ -152,6 +155,15 @@ bool insns_not_supported(union loongarch_instruction insn)
 		return true;
 	}
 
+	switch (insn.reg2_format.opcode) {
+	case llacqw_op:
+	case llacqd_op:
+	case screlw_op:
+	case screld_op:
+		pr_notice("llacq and screl instructions are not supported\n");
+		return true;
+	}
+
 	switch (insn.reg1i21_format.opcode) {
 	case bceqz_op:
 		pr_notice("bceqz and bcnez instructions are not supported\n");
diff --git a/arch/loongarch/kernel/kexec_efi.c b/arch/loongarch/kernel/kexec_efi.c
new file mode 100644
index 000000000000..45121b914f8f
--- /dev/null
+++ b/arch/loongarch/kernel/kexec_efi.c
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Load EFI vmlinux file for the kexec_file_load syscall.
+ *
+ * Author: Youling Tang <tangyouling@kylinos.cn>
+ * Copyright (C) 2025 KylinSoft Corporation.
+ */
+
+#define pr_fmt(fmt)	"kexec_file(EFI): " fmt
+
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/kexec.h>
+#include <linux/pe.h>
+#include <linux/string.h>
+#include <asm/byteorder.h>
+#include <asm/cpufeature.h>
+#include <asm/image.h>
+
+static int efi_kexec_probe(const char *kernel_buf, unsigned long kernel_len)
+{
+	const struct loongarch_image_header *h = (const struct loongarch_image_header *)kernel_buf;
+
+	if (!h || (kernel_len < sizeof(*h))) {
+		kexec_dprintk("No LoongArch image header.\n");
+		return -EINVAL;
+	}
+
+	if (!loongarch_header_check_dos_sig(h)) {
+		kexec_dprintk("No LoongArch PE image header.\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void *efi_kexec_load(struct kimage *image,
+				char *kernel, unsigned long kernel_len,
+				char *initrd, unsigned long initrd_len,
+				char *cmdline, unsigned long cmdline_len)
+{
+	int ret;
+	unsigned long text_offset, kernel_segment_number;
+	struct kexec_buf kbuf;
+	struct kexec_segment *kernel_segment;
+	struct loongarch_image_header *h;
+
+	h = (struct loongarch_image_header *)kernel;
+	if (!h->kernel_asize)
+		return ERR_PTR(-EINVAL);
+
+	/*
+	 * Load the kernel
+	 * FIXME: Non-relocatable kernel rejected for kexec_file (require CONFIG_RELOCATABLE)
+	 */
+	kbuf.image = image;
+	kbuf.buf_max = ULONG_MAX;
+	kbuf.top_down = false;
+
+	kbuf.buffer = kernel;
+	kbuf.bufsz = kernel_len;
+	kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
+	kbuf.memsz = le64_to_cpu(h->kernel_asize);
+	text_offset = le64_to_cpu(h->text_offset);
+	kbuf.buf_min = text_offset;
+	kbuf.buf_align = SZ_2M;
+
+	kernel_segment_number = image->nr_segments;
+
+	/*
+	 * The location of the kernel segment may make it impossible to
+	 * satisfy the other segment requirements, so we try repeatedly
+	 * to find a location that will work.
+	 */
+	while ((ret = kexec_add_buffer(&kbuf)) == 0) {
+		/* Try to load additional data */
+		kernel_segment = &image->segment[kernel_segment_number];
+		ret = load_other_segments(image, kernel_segment->mem,
+					  kernel_segment->memsz, initrd,
+					  initrd_len, cmdline, cmdline_len);
+		if (!ret)
+			break;
+
+		/*
+		 * We couldn't find space for the other segments; erase the
+		 * kernel segment and try the next available hole.
+		 */
+		image->nr_segments -= 1;
+		kbuf.buf_min = kernel_segment->mem + kernel_segment->memsz;
+		kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
+	}
+
+	if (ret < 0) {
+		pr_err("Could not find any suitable kernel location!");
+		return ERR_PTR(ret);
+	}
+
+	kernel_segment = &image->segment[kernel_segment_number];
+
+	/* Make sure the second kernel jumps to the correct "kernel_entry" */
+	image->start = kernel_segment->mem + h->kernel_entry - text_offset;
+
+	kexec_dprintk("Loaded kernel at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+		      kernel_segment->mem, kbuf.bufsz, kernel_segment->memsz);
+
+	return NULL;
+}
+
+const struct kexec_file_ops kexec_efi_ops = {
+	.probe = efi_kexec_probe,
+	.load = efi_kexec_load,
+};
diff --git a/arch/loongarch/kernel/kexec_elf.c b/arch/loongarch/kernel/kexec_elf.c
new file mode 100644
index 000000000000..97b2f049801a
--- /dev/null
+++ b/arch/loongarch/kernel/kexec_elf.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Load ELF vmlinux file for the kexec_file_load syscall.
+ *
+ * Author: Youling Tang <tangyouling@kylinos.cn>
+ * Copyright (C) 2025 KylinSoft Corporation.
+ */
+
+#define pr_fmt(fmt)	"kexec_file(ELF): " fmt
+
+#include <linux/elf.h>
+#include <linux/kexec.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/memblock.h>
+#include <asm/setup.h>
+
+#define elf_kexec_probe kexec_elf_probe
+
+static int _elf_kexec_load(struct kimage *image,
+			   struct elfhdr *ehdr, struct kexec_elf_info *elf_info,
+			   struct kexec_buf *kbuf, unsigned long *text_offset)
+{
+	int i, ret = -1;
+
+	/* Read in the PT_LOAD segments. */
+	for (i = 0; i < ehdr->e_phnum; i++) {
+		size_t size;
+		const struct elf_phdr *phdr;
+
+		phdr = &elf_info->proghdrs[i];
+		if (phdr->p_type != PT_LOAD)
+			continue;
+
+		size = phdr->p_filesz;
+		if (size > phdr->p_memsz)
+			size = phdr->p_memsz;
+
+		kbuf->buffer = (void *)elf_info->buffer + phdr->p_offset;
+		kbuf->bufsz = size;
+		kbuf->buf_align = phdr->p_align;
+		*text_offset = __pa(phdr->p_paddr);
+		kbuf->buf_min = *text_offset;
+		kbuf->memsz = ALIGN(phdr->p_memsz, SZ_64K);
+		kbuf->mem = KEXEC_BUF_MEM_UNKNOWN;
+		ret = kexec_add_buffer(kbuf);
+		if (ret < 0)
+			break;
+	}
+
+	return ret;
+}
+
+static void *elf_kexec_load(struct kimage *image,
+			    char *kernel, unsigned long kernel_len,
+			    char *initrd, unsigned long initrd_len,
+			    char *cmdline, unsigned long cmdline_len)
+{
+	int ret;
+	unsigned long text_offset, kernel_segment_number;
+	struct elfhdr ehdr;
+	struct kexec_buf kbuf;
+	struct kexec_elf_info elf_info;
+	struct kexec_segment *kernel_segment;
+
+	ret = kexec_build_elf_info(kernel, kernel_len, &ehdr, &elf_info);
+	if (ret < 0)
+		return ERR_PTR(ret);
+
+	/*
+	 * Load the kernel
+	 * FIXME: Non-relocatable kernel rejected for kexec_file (require CONFIG_RELOCATABLE)
+	 */
+	kbuf.image = image;
+	kbuf.buf_max = ULONG_MAX;
+	kbuf.top_down = false;
+
+	kernel_segment_number = image->nr_segments;
+
+	ret = _elf_kexec_load(image, &ehdr, &elf_info, &kbuf, &text_offset);
+	if (ret < 0)
+		goto out;
+
+	/* Load additional data */
+	kernel_segment = &image->segment[kernel_segment_number];
+	ret = load_other_segments(image, kernel_segment->mem, kernel_segment->memsz,
+				  initrd, initrd_len, cmdline, cmdline_len);
+	if (ret < 0)
+		goto out;
+
+	/* Make sure the second kernel jumps to the correct "kernel_entry". */
+	image->start = kernel_segment->mem + __pa(ehdr.e_entry) - text_offset;
+
+	kexec_dprintk("Loaded kernel at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+		      kernel_segment->mem, kbuf.bufsz, kernel_segment->memsz);
+
+out:
+	kexec_free_elf_info(&elf_info);
+	return ret ? ERR_PTR(ret) : NULL;
+}
+
+const struct kexec_file_ops kexec_elf_ops = {
+	.probe = elf_kexec_probe,
+	.load  = elf_kexec_load,
+};
diff --git a/arch/loongarch/kernel/machine_kexec.c b/arch/loongarch/kernel/machine_kexec.c
index f9381800e291..e4b2bbc47e62 100644
--- a/arch/loongarch/kernel/machine_kexec.c
+++ b/arch/loongarch/kernel/machine_kexec.c
@@ -70,18 +70,28 @@ int machine_kexec_prepare(struct kimage *kimage)
 	kimage->arch.efi_boot = fw_arg0;
 	kimage->arch.systable_ptr = fw_arg2;
 
-	/* Find the command line */
-	for (i = 0; i < kimage->nr_segments; i++) {
-		if (!strncmp(bootloader, (char __user *)kimage->segment[i].buf, strlen(bootloader))) {
-			if (!copy_from_user(cmdline_ptr, kimage->segment[i].buf, COMMAND_LINE_SIZE))
-				kimage->arch.cmdline_ptr = (unsigned long)cmdline_ptr;
-			break;
+	if (kimage->file_mode == 1) {
+		/*
+		 * kimage->cmdline_buf will be released in kexec_file_load, so copy
+		 * to the KEXEC_CMDLINE_ADDR safe area.
+		 */
+		memcpy((void *)KEXEC_CMDLINE_ADDR, (void *)kimage->arch.cmdline_ptr,
+					strlen((char *)kimage->arch.cmdline_ptr) + 1);
+		kimage->arch.cmdline_ptr = (unsigned long)KEXEC_CMDLINE_ADDR;
+	} else {
+		/* Find the command line */
+		for (i = 0; i < kimage->nr_segments; i++) {
+			if (!strncmp(bootloader, (char __user *)kimage->segment[i].buf, strlen(bootloader))) {
+				if (!copy_from_user(cmdline_ptr, kimage->segment[i].buf, COMMAND_LINE_SIZE))
+					kimage->arch.cmdline_ptr = (unsigned long)cmdline_ptr;
+				break;
+			}
 		}
-	}
 
-	if (!kimage->arch.cmdline_ptr) {
-		pr_err("Command line not included in the provided image\n");
-		return -EINVAL;
+		if (!kimage->arch.cmdline_ptr) {
+			pr_err("Command line not included in the provided image\n");
+			return -EINVAL;
+		}
 	}
 
 	/* kexec/kdump need a safe page to save reboot_code_buffer */
@@ -287,9 +297,10 @@ void machine_kexec(struct kimage *image)
 	/* We do not want to be bothered. */
 	local_irq_disable();
 
-	pr_notice("EFI boot flag 0x%lx\n", efi_boot);
-	pr_notice("Command line at 0x%lx\n", cmdline_ptr);
-	pr_notice("System table at 0x%lx\n", systable_ptr);
+	pr_notice("EFI boot flag: 0x%lx\n", efi_boot);
+	pr_notice("Command line addr: 0x%lx\n", cmdline_ptr);
+	pr_notice("Command line string: %s\n", (char *)cmdline_ptr);
+	pr_notice("System table addr: 0x%lx\n", systable_ptr);
 	pr_notice("We will call new kernel at 0x%lx\n", start_addr);
 	pr_notice("Bye ...\n");
 
diff --git a/arch/loongarch/kernel/machine_kexec_file.c b/arch/loongarch/kernel/machine_kexec_file.c
new file mode 100644
index 000000000000..dda236b51a88
--- /dev/null
+++ b/arch/loongarch/kernel/machine_kexec_file.c
@@ -0,0 +1,239 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * kexec_file for LoongArch
+ *
+ * Author: Youling Tang <tangyouling@kylinos.cn>
+ * Copyright (C) 2025 KylinSoft Corporation.
+ *
+ * Most code is derived from LoongArch port of kexec-tools
+ */
+
+#define pr_fmt(fmt) "kexec_file: " fmt
+
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/kexec.h>
+#include <linux/memblock.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/vmalloc.h>
+#include <asm/bootinfo.h>
+
+const struct kexec_file_ops * const kexec_file_loaders[] = {
+	&kexec_efi_ops,
+	&kexec_elf_ops,
+	NULL
+};
+
+int arch_kimage_file_post_load_cleanup(struct kimage *image)
+{
+	vfree(image->elf_headers);
+	image->elf_headers = NULL;
+	image->elf_headers_sz = 0;
+
+	return kexec_image_post_load_cleanup_default(image);
+}
+
+/* Add the "kexec_file" command line parameter to command line. */
+static void cmdline_add_loader(unsigned long *cmdline_tmplen, char *modified_cmdline)
+{
+	int loader_strlen;
+
+	loader_strlen = sprintf(modified_cmdline + (*cmdline_tmplen), "kexec_file ");
+	*cmdline_tmplen += loader_strlen;
+}
+
+/* Add the "initrd=start,size" command line parameter to command line. */
+static void cmdline_add_initrd(struct kimage *image, unsigned long *cmdline_tmplen,
+				char *modified_cmdline, unsigned long initrd)
+{
+	int initrd_strlen;
+
+	initrd_strlen = sprintf(modified_cmdline + (*cmdline_tmplen), "initrd=0x%lx,0x%lx ",
+		initrd, image->initrd_buf_len);
+	*cmdline_tmplen += initrd_strlen;
+}
+
+#ifdef CONFIG_CRASH_DUMP
+
+static int prepare_elf_headers(void **addr, unsigned long *sz)
+{
+	int ret, nr_ranges;
+	uint64_t i;
+	phys_addr_t start, end;
+	struct crash_mem *cmem;
+
+	nr_ranges = 2; /* for exclusion of crashkernel region */
+	for_each_mem_range(i, &start, &end)
+		nr_ranges++;
+
+	cmem = kmalloc(struct_size(cmem, ranges, nr_ranges), GFP_KERNEL);
+	if (!cmem)
+		return -ENOMEM;
+
+	cmem->max_nr_ranges = nr_ranges;
+	cmem->nr_ranges = 0;
+	for_each_mem_range(i, &start, &end) {
+		cmem->ranges[cmem->nr_ranges].start = start;
+		cmem->ranges[cmem->nr_ranges].end = end - 1;
+		cmem->nr_ranges++;
+	}
+
+	/* Exclude crashkernel region */
+	ret = crash_exclude_mem_range(cmem, crashk_res.start, crashk_res.end);
+	if (ret < 0)
+		goto out;
+
+	if (crashk_low_res.end) {
+		ret = crash_exclude_mem_range(cmem, crashk_low_res.start, crashk_low_res.end);
+		if (ret < 0)
+			goto out;
+	}
+
+	ret = crash_prepare_elf64_headers(cmem, true, addr, sz);
+
+out:
+	kfree(cmem);
+	return ret;
+}
+
+/*
+ * Add the "mem=size@start" command line parameter to command line, indicating the
+ * memory region the new kernel can use to boot into.
+ */
+static void cmdline_add_mem(unsigned long *cmdline_tmplen, char *modified_cmdline)
+{
+	int mem_strlen = 0;
+
+	mem_strlen = sprintf(modified_cmdline + (*cmdline_tmplen), "mem=0x%llx@0x%llx ",
+		crashk_res.end - crashk_res.start + 1, crashk_res.start);
+	*cmdline_tmplen += mem_strlen;
+
+	if (crashk_low_res.end) {
+		mem_strlen = sprintf(modified_cmdline + (*cmdline_tmplen), "mem=0x%llx@0x%llx ",
+			crashk_low_res.end - crashk_low_res.start + 1, crashk_low_res.start);
+		*cmdline_tmplen += mem_strlen;
+	}
+}
+
+/* Add the "elfcorehdr=size@start" command line parameter to command line. */
+static void cmdline_add_elfcorehdr(struct kimage *image, unsigned long *cmdline_tmplen,
+				   char *modified_cmdline, unsigned long elfcorehdr_sz)
+{
+	int elfcorehdr_strlen = 0;
+
+	elfcorehdr_strlen = sprintf(modified_cmdline + (*cmdline_tmplen), "elfcorehdr=0x%lx@0x%lx ",
+		elfcorehdr_sz, image->elf_load_addr);
+	*cmdline_tmplen += elfcorehdr_strlen;
+}
+
+#endif
+
+/*
+ * Try to add the initrd to the image. If it is not possible to find valid
+ * locations, this function will undo changes to the image and return non zero.
+ */
+int load_other_segments(struct kimage *image,
+			unsigned long kernel_load_addr, unsigned long kernel_size,
+			char *initrd, unsigned long initrd_len, char *cmdline, unsigned long cmdline_len)
+{
+	int ret = 0;
+	unsigned long cmdline_tmplen = 0;
+	unsigned long initrd_load_addr = 0;
+	unsigned long orig_segments = image->nr_segments;
+	char *modified_cmdline = NULL;
+	struct kexec_buf kbuf;
+
+	kbuf.image = image;
+	/* Don't allocate anything below the kernel */
+	kbuf.buf_min = kernel_load_addr + kernel_size;
+
+	modified_cmdline = kzalloc(COMMAND_LINE_SIZE, GFP_KERNEL);
+	if (!modified_cmdline)
+		return -EINVAL;
+
+	cmdline_add_loader(&cmdline_tmplen, modified_cmdline);
+	/* Ensure it's null terminated */
+	modified_cmdline[COMMAND_LINE_SIZE - 1] = '\0';
+
+#ifdef CONFIG_CRASH_DUMP
+	/* Load elf core header */
+	if (image->type == KEXEC_TYPE_CRASH) {
+		void *headers;
+		unsigned long headers_sz;
+
+		ret = prepare_elf_headers(&headers, &headers_sz);
+		if (ret < 0) {
+			pr_err("Preparing elf core header failed\n");
+			goto out_err;
+		}
+
+		kbuf.buffer = headers;
+		kbuf.bufsz = headers_sz;
+		kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
+		kbuf.memsz = headers_sz;
+		kbuf.buf_align = SZ_64K; /* largest supported page size */
+		kbuf.buf_max = ULONG_MAX;
+		kbuf.top_down = true;
+
+		ret = kexec_add_buffer(&kbuf);
+		if (ret < 0) {
+			vfree(headers);
+			goto out_err;
+		}
+		image->elf_headers = headers;
+		image->elf_load_addr = kbuf.mem;
+		image->elf_headers_sz = headers_sz;
+
+		kexec_dprintk("Loaded elf core header at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+			      image->elf_load_addr, kbuf.bufsz, kbuf.memsz);
+
+		/* Add the mem=size@start parameter to the command line */
+		cmdline_add_mem(&cmdline_tmplen, modified_cmdline);
+
+		/* Add the elfcorehdr=size@start parameter to the command line */
+		cmdline_add_elfcorehdr(image, &cmdline_tmplen, modified_cmdline, headers_sz);
+	}
+#endif
+
+	/* Load initrd */
+	if (initrd) {
+		kbuf.buffer = initrd;
+		kbuf.bufsz = initrd_len;
+		kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
+		kbuf.memsz = initrd_len;
+		kbuf.buf_align = 0;
+		/* within 1GB-aligned window of up to 32GB in size */
+		kbuf.buf_max = round_down(kernel_load_addr, SZ_1G) + (unsigned long)SZ_1G * 32;
+		kbuf.top_down = false;
+
+		ret = kexec_add_buffer(&kbuf);
+		if (ret < 0)
+			goto out_err;
+		initrd_load_addr = kbuf.mem;
+
+		kexec_dprintk("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+			      initrd_load_addr, kbuf.bufsz, kbuf.memsz);
+
+		/* Add the initrd=start,size parameter to the command line */
+		cmdline_add_initrd(image, &cmdline_tmplen, modified_cmdline, initrd_load_addr);
+	}
+
+	if (cmdline_len + cmdline_tmplen > COMMAND_LINE_SIZE) {
+		pr_err("Appending command line exceeds COMMAND_LINE_SIZE\n");
+		ret = -EINVAL;
+		goto out_err;
+	}
+
+	memcpy(modified_cmdline + cmdline_tmplen, cmdline, cmdline_len);
+	cmdline = modified_cmdline;
+	image->arch.cmdline_ptr = (unsigned long)cmdline;
+
+	return 0;
+
+out_err:
+	image->nr_segments = orig_segments;
+	kfree(modified_cmdline);
+	return ret;
+}
diff --git a/arch/loongarch/kernel/module-sections.c b/arch/loongarch/kernel/module-sections.c
index e2f30ff9afde..a43ba7f9f987 100644
--- a/arch/loongarch/kernel/module-sections.c
+++ b/arch/loongarch/kernel/module-sections.c
@@ -8,6 +8,7 @@
 #include <linux/module.h>
 #include <linux/moduleloader.h>
 #include <linux/ftrace.h>
+#include <linux/sort.h>
 
 Elf_Addr module_emit_got_entry(struct module *mod, Elf_Shdr *sechdrs, Elf_Addr val)
 {
@@ -61,39 +62,38 @@ Elf_Addr module_emit_plt_entry(struct module *mod, Elf_Shdr *sechdrs, Elf_Addr v
 	return (Elf_Addr)&plt[nr];
 }
 
-static int is_rela_equal(const Elf_Rela *x, const Elf_Rela *y)
-{
-	return x->r_info == y->r_info && x->r_addend == y->r_addend;
-}
+#define cmp_3way(a, b)  ((a) < (b) ? -1 : (a) > (b))
 
-static bool duplicate_rela(const Elf_Rela *rela, int idx)
+static int compare_rela(const void *x, const void *y)
 {
-	int i;
+	int ret;
+	const Elf_Rela *rela_x = x, *rela_y = y;
 
-	for (i = 0; i < idx; i++) {
-		if (is_rela_equal(&rela[i], &rela[idx]))
-			return true;
-	}
+	ret = cmp_3way(rela_x->r_info, rela_y->r_info);
+	if (ret == 0)
+		ret = cmp_3way(rela_x->r_addend, rela_y->r_addend);
 
-	return false;
+	return ret;
 }
 
 static void count_max_entries(Elf_Rela *relas, int num,
 			      unsigned int *plts, unsigned int *gots)
 {
-	unsigned int i, type;
+	unsigned int i;
+
+	sort(relas, num, sizeof(Elf_Rela), compare_rela, NULL);
 
 	for (i = 0; i < num; i++) {
-		type = ELF_R_TYPE(relas[i].r_info);
-		switch (type) {
+		if (i && !compare_rela(&relas[i-1], &relas[i]))
+			continue;
+
+		switch (ELF_R_TYPE(relas[i].r_info)) {
 		case R_LARCH_SOP_PUSH_PLT_PCREL:
 		case R_LARCH_B26:
-			if (!duplicate_rela(relas, i))
-				(*plts)++;
+			(*plts)++;
 			break;
 		case R_LARCH_GOT_PC_HI20:
-			if (!duplicate_rela(relas, i))
-				(*gots)++;
+			(*gots)++;
 			break;
 		default:
 			break; /* Do nothing. */
diff --git a/arch/loongarch/kernel/process.c b/arch/loongarch/kernel/process.c
index 3582f591bab2..efd9edf65603 100644
--- a/arch/loongarch/kernel/process.c
+++ b/arch/loongarch/kernel/process.c
@@ -167,7 +167,7 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
 	unsigned long childksp;
 	unsigned long tls = args->tls;
 	unsigned long usp = args->stack;
-	unsigned long clone_flags = args->flags;
+	u64 clone_flags = args->flags;
 	struct pt_regs *childregs, *regs = current_pt_regs();
 
 	childksp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
diff --git a/arch/loongarch/kernel/relocate.c b/arch/loongarch/kernel/relocate.c
index 50c469067f3a..b5e2312a2fca 100644
--- a/arch/loongarch/kernel/relocate.c
+++ b/arch/loongarch/kernel/relocate.c
@@ -166,6 +166,10 @@ static inline __init bool kaslr_disabled(void)
 		return true;
 #endif
 
+	str = strstr(boot_command_line, "kexec_file");
+	if (str == boot_command_line || (str > boot_command_line && *(str - 1) == ' '))
+		return true;
+
 	return false;
 }
 
diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c
index 075b79b2c1d3..69c17d162fff 100644
--- a/arch/loongarch/kernel/setup.c
+++ b/arch/loongarch/kernel/setup.c
@@ -355,6 +355,7 @@ void __init platform_init(void)
 
 #ifdef CONFIG_ACPI
 	acpi_table_upgrade();
+	acpi_gbl_use_global_lock = false;
 	acpi_gbl_use_default_register_widths = false;
 	acpi_boot_table_init();
 #endif
diff --git a/arch/loongarch/kernel/signal.c b/arch/loongarch/kernel/signal.c
index 4740cb5b2388..c9f7ca778364 100644
--- a/arch/loongarch/kernel/signal.c
+++ b/arch/loongarch/kernel/signal.c
@@ -677,6 +677,11 @@ static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
 	for (i = 1; i < 32; i++)
 		err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
 
+#ifdef CONFIG_CPU_HAS_LBT
+	if (extctx->lbt.addr)
+		err |= protected_save_lbt_context(extctx);
+#endif
+
 	if (extctx->lasx.addr)
 		err |= protected_save_lasx_context(extctx);
 	else if (extctx->lsx.addr)
@@ -684,11 +689,6 @@ static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
 	else if (extctx->fpu.addr)
 		err |= protected_save_fpu_context(extctx);
 
-#ifdef CONFIG_CPU_HAS_LBT
-	if (extctx->lbt.addr)
-		err |= protected_save_lbt_context(extctx);
-#endif
-
 	/* Set the "end" magic */
 	info = (struct sctx_info *)extctx->end.addr;
 	err |= __put_user(0, &info->magic);
diff --git a/arch/loongarch/kernel/stacktrace.c b/arch/loongarch/kernel/stacktrace.c
index 9a038d1070d7..387dc4d3c486 100644
--- a/arch/loongarch/kernel/stacktrace.c
+++ b/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)) {
diff --git a/arch/loongarch/kernel/time.c b/arch/loongarch/kernel/time.c
index 367906b10f81..6fb92cc1a4c9 100644
--- a/arch/loongarch/kernel/time.c
+++ b/arch/loongarch/kernel/time.c
@@ -5,6 +5,7 @@
  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
  */
 #include <linux/clockchips.h>
+#include <linux/cpuhotplug.h>
 #include <linux/delay.h>
 #include <linux/export.h>
 #include <linux/init.h>
@@ -102,6 +103,21 @@ static int constant_timer_next_event(unsigned long delta, struct clock_event_dev
 	return 0;
 }
 
+static int arch_timer_starting(unsigned int cpu)
+{
+	set_csr_ecfg(ECFGF_TIMER);
+
+	return 0;
+}
+
+static int arch_timer_dying(unsigned int cpu)
+{
+	/* Clear Timer Interrupt */
+	write_csr_tintclear(CSR_TINTCLR_TI);
+
+	return 0;
+}
+
 static unsigned long get_loops_per_jiffy(void)
 {
 	unsigned long lpj = (unsigned long)const_clock_freq;
@@ -172,6 +188,10 @@ int constant_clockevent_init(void)
 	lpj_fine = get_loops_per_jiffy();
 	pr_info("Constant clock event device register\n");
 
+	cpuhp_setup_state(CPUHP_AP_LOONGARCH_ARCH_TIMER_STARTING,
+			  "clockevents/loongarch/timer:starting",
+			  arch_timer_starting, arch_timer_dying);
+
 	return 0;
 }
 
diff --git a/arch/loongarch/kernel/vdso.c b/arch/loongarch/kernel/vdso.c
index 7b888d9085a0..dee1a15d7f4c 100644
--- a/arch/loongarch/kernel/vdso.c
+++ b/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);