From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-188.mta0.migadu.com (out-188.mta0.migadu.com [91.218.175.188]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 72DE122172E for ; Wed, 3 Sep 2025 03:02:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.188 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756868545; cv=none; b=k+G/Jgx5FJmnzCBzkrsQLIQorYtszRQjwEB772yrbKUPa8sodM95rQkFwCd4BfD30DmDt3WRklwomc4HSp0+qdV2NUgrMETre8cq46uem7U5LJBL2j4jOsE2B+AyeBojXIjZ8mLXLW9rArNfbzphuxLXoH0ZkUz3q5X3X6MocUY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756868545; c=relaxed/simple; bh=mqb600+pneecQKzsZoignJ/8aykXWDyXNzFUolsqzrw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Y4jKomXZqf9K3tQnRQTqk3LGXdOjCLUVnLucqpBu2W+2CTFZPAt9kP3rLRnL/jkYSm27H54+Ibj0pqMI4p8WTgiwnrmcY+ZZ49movuv+w/aHzmxX9A5K8CUaBen35/PTrQzZ+soDTtdbA5wTfOca8DaLjR+ToXomHvBU+U1ZBeg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=VthOXtS9; arc=none smtp.client-ip=91.218.175.188 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="VthOXtS9" 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=1756868541; 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=3Y/9kZHekM+gIBRRUe68eDicKpPDtNyELOaDeeOu0CE=; b=VthOXtS91xS1dwsI7nuJzwzt7lhGfFY3j33cNwgTp64x7gCkivNXJwTi4G8iB9N8gEoMBE ffVKs54+iChzx6YS1RvXAeYHuszCM7hNfRvXHdnZjky6dpzMZKCPw47NVlKro57ZNGe/Kh NknhUZ1S70FseA816Wy9fc8gIVpkAtg= 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 v4 3/7] LoongArch/kexec_file: Support loading EFI binary file Date: Wed, 3 Sep 2025 11:00:56 +0800 Message-Id: <20250903030100.196744-4-youling.tang@linux.dev> In-Reply-To: <20250903030100.196744-1-youling.tang@linux.dev> References: <20250903030100.196744-1-youling.tang@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT From: Youling Tang This patch creates kexec_efi_ops to load EFI binary file for kexec_file_load() syscall. 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) Currently, pez(vmlinuz.efi) and pei(vmlinux.efi) format images are supported. The basic usage (vmlinuz.efi or vmlinux.efi): 1) Load second kernel image: # kexec -s -l vmlinuz.efi --initrd=initrd.img --reuse-cmdline 2) Startup second kernel: # kexec -e Signed-off-by: Youling Tang --- arch/loongarch/include/asm/image.h | 17 +++ arch/loongarch/include/asm/kexec.h | 1 + arch/loongarch/kernel/Makefile | 2 +- arch/loongarch/kernel/kexec_efi.c | 114 +++++++++++++++++++++ arch/loongarch/kernel/machine_kexec_file.c | 1 + 5 files changed, 134 insertions(+), 1 deletion(-) create mode 100644 arch/loongarch/kernel/kexec_efi.c diff --git a/arch/loongarch/include/asm/image.h b/arch/loongarch/include/asm/image.h index ff539711c9ea..982cebd31cac 100644 --- a/arch/loongarch/include/asm/image.h +++ b/arch/loongarch/include/asm/image.h @@ -32,5 +32,22 @@ struct loongarch_image_header { uint32_t pe_header; }; +static const uint8_t loongarch_image_dos_sig[2] = {'M', 'Z'}; + +/** + * loongarch_header_check_dos_sig - Helper to check the loongarch image header. + * + * Returns non-zero if 'MZ' signature is found. + */ + +static inline int loongarch_header_check_dos_sig(const struct loongarch_image_header *h) +{ + if (!h) + return 0; + + return (h->dos_sig[0] == loongarch_image_dos_sig[0] + && h->dos_sig[1] == loongarch_image_dos_sig[1]); +} + #endif /* __ASSEMBLER__ */ #endif /* __ASM_IMAGE_H */ diff --git a/arch/loongarch/include/asm/kexec.h b/arch/loongarch/include/asm/kexec.h index ed7e3fc8571e..34799db933fb 100644 --- a/arch/loongarch/include/asm/kexec.h +++ b/arch/loongarch/include/asm/kexec.h @@ -42,6 +42,7 @@ struct kimage_arch { }; #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 diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile index 67b9b214d212..dd6183f353e6 100644 --- a/arch/loongarch/kernel/Makefile +++ b/arch/loongarch/kernel/Makefile @@ -62,7 +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-$(CONFIG_KEXEC_FILE) += machine_kexec_file.o kexec_efi.o obj-$(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..e02fd88cf5d0 --- /dev/null +++ b/arch/loongarch/kernel/kexec_efi.c @@ -0,0 +1,114 @@ +// 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_dos_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->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) { + 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_file.c b/arch/loongarch/kernel/machine_kexec_file.c index 584ce9471e93..a454e9dfc339 100644 --- a/arch/loongarch/kernel/machine_kexec_file.c +++ b/arch/loongarch/kernel/machine_kexec_file.c @@ -21,6 +21,7 @@ #include const struct kexec_file_ops * const kexec_file_loaders[] = { + &kexec_efi_ops, NULL }; -- 2.43.0