From nobody Sun Oct 5 03:35:12 2025 Received: from out-178.mta1.migadu.com (out-178.mta1.migadu.com [95.215.58.178]) (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 E9F5C2DECAA for ; Mon, 11 Aug 2025 09:28:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.178 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754904500; cv=none; b=lnDUD9FsbI3VVRPWyHQQzXys1L1M3YbVVkbpr/TTWqlT43uX0cET7/9SBZ6MRyqHlQjqDJZUHT9/+oZ7eG6DEt/k3w3xsM54ckDtu4SnblTA6ZnI+Kd42VKq5G7YyOFTsLRVysC04mMAz9fyFNJG/IGX1HTyo3ZwQ3PRO+UDS3w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754904500; c=relaxed/simple; bh=6RMVgeBehurPfBfL/r9EvLbL3T6ZeyXaePSaxIzUJDE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=DqeTnG0ABgeRW5NSUCYjo7crbP8qt3eXsokLb5R0VF9kbzTvljJoxafgcIh+1BswDO0eQpUVVWSUxOmX1CSMiKj4fxfyeWXanxz0Vz9l+GvxdY2Lo4QlU2i6VpjVcGvWHFm0m2GELbUziLlGG+W+G190xjKBBTfH/vv36Bdjndk= 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=gZvEZYbD; arc=none smtp.client-ip=95.215.58.178 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="gZvEZYbD" 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=1754904496; 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=/OGdEPpBUhj7h+P7gI7AN/cn/c6kSjD1T1RA7M9+TKc=; b=gZvEZYbDwNfEHgTALwzWVqLWcoB0NLvOAWdYQodiEA5lGNODD0kwbO1cMffi17+D9hf6MH jFOJk8exjf263bohWMQwNU/3KW/TYRVHyYARFeJj0sCU6UVSNePfEPscw4QXNG5Ho6O2Y4 WILibzRKykahmiLa/CABSqALtyanJWk= From: Youling Tang To: Huacai Chen Cc: WANG Xuerui , Baoquan He , kexec@lists.infradead.org, loongarch@lists.linux.dev, linux-kernel@vger.kernel.org, youling.tang@linux.dev, Youling Tang Subject: [PATCH 2/6] LoongArch: Add kexec_file support Date: Mon, 11 Aug 2025 17:26:55 +0800 Message-Id: <20250811092659.14903-3-youling.tang@linux.dev> In-Reply-To: <20250811092659.14903-1-youling.tang@linux.dev> References: <20250811092659.14903-1-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: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" From: Youling Tang This patch adds support for kexec_file on LoongArch. The image_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 supporte= d, but ELF format is not supported. Signed-off-by: Youling Tang --- arch/loongarch/Kconfig | 8 ++ arch/loongarch/include/asm/image.h | 18 ++++ arch/loongarch/include/asm/kexec.h | 12 +++ arch/loongarch/kernel/Makefile | 1 + arch/loongarch/kernel/kexec_image.c | 112 +++++++++++++++++++++ arch/loongarch/kernel/machine_kexec.c | 33 ++++-- arch/loongarch/kernel/machine_kexec_file.c | 46 +++++++++ 7 files changed, 219 insertions(+), 11 deletions(-) create mode 100644 arch/loongarch/kernel/kexec_image.c create mode 100644 arch/loongarch/kernel/machine_kexec_file.c diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index f0abc38c40ac..fd50c83f7827 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -625,6 +625,14 @@ config CPU_HAS_PREFETCH config ARCH_SUPPORTS_KEXEC def_bool y =20 +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 + config ARCH_SUPPORTS_CRASH_DUMP def_bool y =20 diff --git a/arch/loongarch/include/asm/image.h b/arch/loongarch/include/as= m/image.h index 1f090736e71d..829e1ecb1f5d 100644 --- a/arch/loongarch/include/asm/image.h +++ b/arch/loongarch/include/asm/image.h @@ -36,5 +36,23 @@ struct loongarch_image_header { uint32_t pe_header; }; =20 +static const uint8_t loongarch_image_pe_sig[2] =3D {'M', 'Z'}; +static const uint8_t loongarch_pe_machtype[6] =3D {'P', 'E', 0x0, 0x0, 0x6= 4, 0x62}; + +/** + * loongarch_header_check_pe_sig - Helper to check the loongarch image hea= der. + * + * Returns non-zero if 'MZ' signature is found. + */ + +static inline int loongarch_header_check_pe_sig(const struct loongarch_ima= ge_header *h) +{ + if (!h) + return 0; + + return (h->pe_sig[0] =3D=3D loongarch_image_pe_sig[0] + && h->pe_sig[1] =3D=3D loongarch_image_pe_sig[1]); +} + #endif /* __ASSEMBLY__ */ #endif /* __ASM_IMAGE_H */ diff --git a/arch/loongarch/include/asm/kexec.h b/arch/loongarch/include/as= m/kexec.h index cf95cd3eb2de..3ef8517a3670 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; }; =20 +#ifdef CONFIG_KEXEC_FILE +extern const struct kexec_file_ops kexec_image_ops; + +int arch_kimage_file_post_load_cleanup(struct kimage *image); +#define arch_kimage_file_post_load_cleanup arch_kimage_file_post_load_clea= nup + +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..bd9405ee3888 100644 --- a/arch/loongarch/kernel/Makefile +++ b/arch/loongarch/kernel/Makefile @@ -62,6 +62,7 @@ obj-$(CONFIG_MAGIC_SYSRQ) +=3D sysrq.o obj-$(CONFIG_RELOCATABLE) +=3D relocate.o =20 obj-$(CONFIG_KEXEC_CORE) +=3D machine_kexec.o relocate_kernel.o +obj-$(CONFIG_KEXEC_FILE) +=3D machine_kexec_file.o kexec_image.o obj-$(CONFIG_CRASH_DUMP) +=3D crash_dump.o =20 obj-$(CONFIG_UNWINDER_GUESS) +=3D unwind_guess.o diff --git a/arch/loongarch/kernel/kexec_image.c b/arch/loongarch/kernel/ke= xec_image.c new file mode 100644 index 000000000000..fdd1845b4e2e --- /dev/null +++ b/arch/loongarch/kernel/kexec_image.c @@ -0,0 +1,112 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Kexec image loader for LoongArch + + * Author: Youling Tang + * Copyright (C) 2025 KylinSoft Corporation. + */ + +#define pr_fmt(fmt) "kexec_file(Image): " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static int image_probe(const char *kernel_buf, unsigned long kernel_len) +{ + const struct loongarch_image_header *h =3D + (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_err("Bad loongarch PE image header.\n"); + return -EINVAL; + } + + return 0; +} + +static void *image_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 =3D (struct loongarch_image_header *)kernel; + if (!h->image_size) + return ERR_PTR(-EINVAL); + + /* Load the kernel */ + kbuf.image =3D image; + kbuf.buf_min =3D 0; + kbuf.buf_max =3D ULONG_MAX; + kbuf.top_down =3D false; + + kbuf.buffer =3D kernel; + kbuf.bufsz =3D kernel_len; + kbuf.mem =3D KEXEC_BUF_MEM_UNKNOWN; + kbuf.memsz =3D le64_to_cpu(h->image_size); + text_offset =3D le64_to_cpu(h->text_offset); + kbuf.buf_align =3D SZ_2M; + + kernel_segment_number =3D 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 =3D kexec_add_buffer(&kbuf)) =3D=3D 0) { + /* Try to load additional data */ + kernel_segment =3D &image->segment[kernel_segment_number]; + ret =3D 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 -=3D 1; + kbuf.buf_min =3D kernel_segment->mem + kernel_segment->memsz; + kbuf.mem =3D KEXEC_BUF_MEM_UNKNOWN; + } + + if (ret) { + pr_err("Could not find any suitable kernel location!"); + return ERR_PTR(ret); + } + + kernel_segment =3D &image->segment[kernel_segment_number]; + + /* Make sure the second kernel jumps to the correct "kernel_entry". */ + image->start =3D kernel_segment->mem + h->kernel_entry - text_offset; + + kexec_dprintk("Loaded kernel at 0x%lx bufsz=3D0x%lx memsz=3D0x%lx\n", + kernel_segment->mem, kbuf.bufsz, + kernel_segment->memsz); + + return NULL; +} + +const struct kexec_file_ops kexec_image_ops =3D { + .probe =3D image_probe, + .load =3D image_load, +}; diff --git a/arch/loongarch/kernel/machine_kexec.c b/arch/loongarch/kernel/= machine_kexec.c index f9381800e291..008f43e26120 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 =3D fw_arg0; kimage->arch.systable_ptr =3D fw_arg2; =20 - /* Find the command line */ - for (i =3D 0; i < kimage->nr_segments; i++) { - if (!strncmp(bootloader, (char __user *)kimage->segment[i].buf, strlen(b= ootloader))) { - if (!copy_from_user(cmdline_ptr, kimage->segment[i].buf, COMMAND_LINE_S= IZE)) - kimage->arch.cmdline_ptr =3D (unsigned long)cmdline_ptr; - break; + if (kimage->file_mode =3D=3D 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 =3D (unsigned long)KEXEC_CMDLINE_ADDR; + } else { + /* Find the command line */ + for (i =3D 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 =3D (unsigned long)cmdline_ptr; + break; + } } - } =20 - 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; + } } =20 /* kexec/kdump need a safe page to save reboot_code_buffer */ @@ -288,7 +298,8 @@ void machine_kexec(struct kimage *image) local_irq_disable(); =20 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 at %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/ke= rnel/machine_kexec_file.c new file mode 100644 index 000000000000..bc91ae0afa4c --- /dev/null +++ b/arch/loongarch/kernel/machine_kexec_file.c @@ -0,0 +1,46 @@ +// 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[] =3D { + &kexec_image_ops, + NULL +}; + +int arch_kimage_file_post_load_cleanup(struct kimage *image) +{ + vfree(image->elf_headers); + image->elf_headers =3D NULL; + image->elf_headers_sz =3D 0; + + return kexec_image_post_load_cleanup_default(image); +} + +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) +{ + image->arch.cmdline_ptr =3D (unsigned long)cmdline; + + return 0; +} --=20 2.34.1