From: Youling Tang Date: Thu, 2 Oct 2025 14:39:07 +0000 (+0800) Subject: LoongArch: Add preparatory infrastructure for kexec_file X-Git-Tag: v6.18-rc1~56^2~17 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d162feec6b6e7ed97986118450812fdd7e9ba202;p=thirdparty%2Fkernel%2Fstable.git LoongArch: Add preparatory infrastructure for kexec_file Add some preparatory infrastructure: - Add command line processing. - Add support for loading other segments. - 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 Signed-off-by: Huacai Chen --- diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index 0631a6b11281..aa1cb1fd3c52 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -633,6 +633,15 @@ 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 64BIT + depends on KEXEC_FILE + select RELOCATABLE + select HAVE_IMA_KEXEC if IMA + 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..9442c7a1c3a6 100644 --- a/arch/loongarch/include/asm/kexec.h +++ b/arch/loongarch/include/asm/kexec.h @@ -41,6 +41,16 @@ 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..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..8e99d2f7165e --- /dev/null +++ b/arch/loongarch/kernel/machine_kexec_file.c @@ -0,0 +1,122 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * kexec_file for LoongArch + * + * Author: Youling Tang + * Copyright (C) 2025 KylinSoft Corporation. + * + * Most code is derived from LoongArch port of kexec-tools + */ + +#define pr_fmt(fmt) "kexec_file: " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +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); +} + +/* 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; +} + +/* + * 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'; + + /* 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; +}