From: Youling Tang <[email protected]> Add some preparatory infrastructure: - Add support for loading other segments. - Add command line processing. - Other minor modifications.
This initrd will be passed to the second kernel via the command line 'initrd=start,size'. The 'kexec_file' command line parameter indicates that the kernel is loaded via kexec_file. Signed-off-by: Youling Tang <[email protected]> --- arch/loongarch/Kconfig | 9 ++ arch/loongarch/include/asm/kexec.h | 11 ++ arch/loongarch/kernel/Makefile | 1 + arch/loongarch/kernel/machine_kexec.c | 37 +++--- arch/loongarch/kernel/machine_kexec_file.c | 126 +++++++++++++++++++++ 5 files changed, 171 insertions(+), 13 deletions(-) create mode 100644 arch/loongarch/kernel/machine_kexec_file.c diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index f0abc38c40ac..490dc6eed749 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -625,6 +625,15 @@ config CPU_HAS_PREFETCH config ARCH_SUPPORTS_KEXEC def_bool y +config ARCH_SUPPORTS_KEXEC_FILE + def_bool 64BIT + +config ARCH_SELECTS_KEXEC_FILE + def_bool y + depends on KEXEC_FILE + select HAVE_IMA_KEXEC if IMA + select RELOCATABLE + config ARCH_SUPPORTS_CRASH_DUMP def_bool y diff --git a/arch/loongarch/include/asm/kexec.h b/arch/loongarch/include/asm/kexec.h index cf95cd3eb2de..ed7e3fc8571e 100644 --- a/arch/loongarch/include/asm/kexec.h +++ b/arch/loongarch/include/asm/kexec.h @@ -41,6 +41,17 @@ struct kimage_arch { unsigned long systable_ptr; }; +#ifdef CONFIG_KEXEC_FILE + +int arch_kimage_file_post_load_cleanup(struct kimage *image); +#define arch_kimage_file_post_load_cleanup arch_kimage_file_post_load_cleanup + +extern 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); +#endif + typedef void (*do_kexec_t)(unsigned long efi_boot, unsigned long cmdline_ptr, unsigned long systable_ptr, diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile index 6f5a4574a911..67b9b214d212 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 obj-$(CONFIG_CRASH_DUMP) += crash_dump.o obj-$(CONFIG_UNWINDER_GUESS) += unwind_guess.o diff --git a/arch/loongarch/kernel/machine_kexec.c b/arch/loongarch/kernel/machine_kexec.c index f9381800e291..d5accdc4576d 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..584ce9471e93 --- /dev/null +++ b/arch/loongarch/kernel/machine_kexec_file.c @@ -0,0 +1,126 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * kexec_file for LoongArch + * + * Author: Youling Tang <[email protected]> + * 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[] = { + 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); +} + +/* Adds 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; +} + +/* Adds the "kexec_file" command line parameter to command line. */ +static void cmdline_add_prefix(unsigned long *cmdline_tmplen, char *modified_cmdline) +{ + int prefix_strlen; + + prefix_strlen = sprintf(modified_cmdline + (*cmdline_tmplen), "kexec_file "); + *cmdline_tmplen += prefix_strlen; +} + +/* + * Tries 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) +{ + struct kexec_buf kbuf; + unsigned long orig_segments = image->nr_segments; + char *modified_cmdline = NULL; + unsigned long cmdline_tmplen = 0; + unsigned long initrd_load_addr = 0; + int ret = 0; + + + kbuf.image = image; + /* not 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_prefix(&cmdline_tmplen, modified_cmdline); + /* Ensure it's null terminated */ + modified_cmdline[COMMAND_LINE_SIZE - 1] = '\0'; + + /* 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) + 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; +} -- 2.43.0
