From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 77C68CA0EFA for ; Wed, 20 Aug 2025 05:58:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=GBzbvApVwC+zuz1F6RmfDj67Mme+a/DUkrAhV+yXG4k=; b=3/Wi29/0O0WRjs2L4CgbC118kq x6p8iFiLar2CrOm2slri+XzFZ5KCVHQCVb0n92sxia/5TBjkk6+UVQh2M2Z150aqQMFlkkSDhM0F2 sJ2W48qECJjjBTnbD8j/RDm/W2QUt/Vvms1jFo+EIq3qqyep5Wb0jbCUNzIlyMsD2s4hlVghRmeRQ x8qtWQOeu7rJzaiC8x+0brnMmRVHJjHI17ZP4WscK93BpTWUjs1Jm9A8am+pKVf4Zo9ffD0VnjJOg hMMHQtzcUeOeCiPtPWGgBPKAy+l70uSq4i/Ra3JUE1B/AZ4eJYxmOixdLIjR+SoFrFwVTZ7wEaG3R GIK4NmJw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uobqA-0000000CSdg-0Lke; Wed, 20 Aug 2025 05:58:30 +0000 Received: from out-170.mta1.migadu.com ([95.215.58.170]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uobpS-0000000CSWy-1Ntk for kexec@lists.infradead.org; Wed, 20 Aug 2025 05:57:48 +0000 X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1755669452; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=GBzbvApVwC+zuz1F6RmfDj67Mme+a/DUkrAhV+yXG4k=; b=qRZf+3mVn8Dt8h+ljDOPv/LrFxVG7+kxLW/U68gtPkcBXZGWNCikFtQ6zhSrWNYqCBMq2b t+9IedNCK+FuYLUWV8dILkup1Pw/cQepSU+oetS1JWNu3ylDDPWxLDO4HyL2iyvV9GabKf wB6Ui7fyOShYbh5EFMCVpMaFYkJhWgw= From: Youling Tang To: Huacai Chen Cc: WANG Xuerui , Baoquan He , Yao Zi , kexec@lists.infradead.org, loongarch@lists.linux.dev, linux-kernel@vger.kernel.org, youling.tang@linux.dev, Youling Tang Subject: [PATCH v2 2/5] LoongArch: Add kexec_file support Date: Wed, 20 Aug 2025 13:56:57 +0800 Message-Id: <20250820055700.24344-3-youling.tang@linux.dev> In-Reply-To: <20250820055700.24344-1-youling.tang@linux.dev> References: <20250820055700.24344-1-youling.tang@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250819_225746_794460_79CA051D X-CRM114-Status: GOOD ( 34.17 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org From: Youling Tang This patch adds support for kexec_file on LoongArch. The efi_kexec_load() as two parts: - the first part loads the kernel image (vmlinuz.efi or vmlinux.efi) - the second part loads other segments (eg: initrd, cmdline) This initrd will be passed to the second kernel via the command line 'initrd=start,size'. Currently, pez(vmlinuz.efi) and pei(vmlinux.efi) format images are supported, but ELF format is not supported. Signed-off-by: Youling Tang --- arch/loongarch/Kconfig | 9 ++ arch/loongarch/include/asm/image.h | 17 +++ arch/loongarch/include/asm/kexec.h | 12 +++ arch/loongarch/kernel/Makefile | 1 + arch/loongarch/kernel/kexec_efi.c | 111 +++++++++++++++++++ arch/loongarch/kernel/machine_kexec.c | 33 ++++-- arch/loongarch/kernel/machine_kexec_file.c | 117 +++++++++++++++++++++ 7 files changed, 289 insertions(+), 11 deletions(-) create mode 100644 arch/loongarch/kernel/kexec_efi.c 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/image.h b/arch/loongarch/include/asm/image.h index 1f090736e71d..655d5836c4e8 100644 --- a/arch/loongarch/include/asm/image.h +++ b/arch/loongarch/include/asm/image.h @@ -36,5 +36,22 @@ struct loongarch_image_header { uint32_t pe_header; }; +static const uint8_t loongarch_image_pe_sig[2] = {'M', 'Z'}; + +/** + * loongarch_header_check_pe_sig - Helper to check the loongarch image header. + * + * Returns non-zero if 'MZ' signature is found. + */ + +static inline int loongarch_header_check_pe_sig(const struct loongarch_image_header *h) +{ + if (!h) + return 0; + + return (h->pe_sig[0] == loongarch_image_pe_sig[0] + && h->pe_sig[1] == loongarch_image_pe_sig[1]); +} + #endif /* __ASSEMBLY__ */ #endif /* __ASM_IMAGE_H */ diff --git a/arch/loongarch/include/asm/kexec.h b/arch/loongarch/include/asm/kexec.h index cf95cd3eb2de..34799db933fb 100644 --- a/arch/loongarch/include/asm/kexec.h +++ b/arch/loongarch/include/asm/kexec.h @@ -41,6 +41,18 @@ struct kimage_arch { unsigned long systable_ptr; }; +#ifdef CONFIG_KEXEC_FILE +extern const struct kexec_file_ops kexec_efi_ops; + +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..dd6183f353e6 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 obj-$(CONFIG_CRASH_DUMP) += crash_dump.o obj-$(CONFIG_UNWINDER_GUESS) += unwind_guess.o diff --git a/arch/loongarch/kernel/kexec_efi.c b/arch/loongarch/kernel/kexec_efi.c new file mode 100644 index 000000000000..7741f1139a12 --- /dev/null +++ b/arch/loongarch/kernel/kexec_efi.c @@ -0,0 +1,111 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Load EFI vmlinux file for the kexec_file_load syscall. + * + * Author: Youling Tang + * Copyright (C) 2025 KylinSoft Corporation. + */ + +#define pr_fmt(fmt) "kexec_file(EFI): " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +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))) { + pr_err("No loongarch image header.\n"); + return -EINVAL; + } + + if (!loongarch_header_check_pe_sig(h)) { + pr_warn("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) +{ + struct loongarch_image_header *h; + struct kexec_buf kbuf; + unsigned long text_offset, kernel_segment_number; + struct kexec_segment *kernel_segment; + int ret; + + h = (struct loongarch_image_header *)kernel; + if (!h->image_size) + return ERR_PTR(-EINVAL); + + /* Load the kernel */ + 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->image_size); + 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) { + 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/machine_kexec.c b/arch/loongarch/kernel/machine_kexec.c index f9381800e291..ba8d64bc6549 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 */ @@ -288,7 +298,8 @@ void machine_kexec(struct kimage *image) 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("Command line addr at 0x%lx\n", cmdline_ptr); + pr_notice("Command line: %s\n", (char *)cmdline_ptr); pr_notice("System table at 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..a713acf32db8 --- /dev/null +++ b/arch/loongarch/kernel/machine_kexec_file.c @@ -0,0 +1,117 @@ +// 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[] = { + &kexec_efi_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); +} + +/* 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; +} + +/* + * 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; + + /* Ensure it's nul 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 cmdline 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