From nobody Fri Oct 3 20:25:01 2025 Received: from out-170.mta0.migadu.com (out-170.mta0.migadu.com [91.218.175.170]) (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 CFDF414A8B for ; Tue, 26 Aug 2025 01:18:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.170 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756171099; cv=none; b=b3xzzEK+WQ/y/ayUmiLnJUkqpDrs9SjLxeef24c3rHhU7bLB8PqpqXdsVp9JbP5tGS6MpoE5LkWE87ZZgB8PNrzcnGYHhvRbyKAxPDggKXx+ySHdjzpwp6KRLLTdintc9uiMq4KWeJQlREZnV/o/0WX5LMTbPdLUN4d9tNPneP4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756171099; c=relaxed/simple; bh=M/+s+Rg4QX0UsMFsO33OqqJGq4/0/8jfcN6CZfBXJDs=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=uAMU+KovMg6DHDvWJItepq5nkhimBtRQslPC0LPObQO8pp9wIQA4qPDeucOLHzeEG1+PSru8evK6cFFEApTLnmN0fk4GiIsEZZ3g/zNyvQCD2Sb4jqJVzJB5tmUEivEo60eRoEzor+Ke6Wpui8Qhx/N2zGVuaWA6TfOqYzTVrBA= 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=FC5NeEge; arc=none smtp.client-ip=91.218.175.170 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="FC5NeEge" 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=1756171095; 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=vujQZVf5TyhJiS/dKOstIc0xO8kGAvT4jnpNPRHbLQw=; b=FC5NeEgeUbXcaF0iEDx97wDIhbn/FsSyd52PpRj3x5cF3HfXw9xErOv3HbwHqxJVh/4Dus k422WrP7miRD28GE2SaqDb+UETa6lB/K1G/wyAJjKHjOuHhyf8OJeub+mZ8efqls3M4/SR PGMcy3H2YUItq8lbbwDj9se2DMKEQtc= 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 v3 1/6] LoongArch: Add struct loongarch_image_header for kernel image Date: Tue, 26 Aug 2025 09:17:17 +0800 Message-Id: <20250826011722.82391-2-youling.tang@linux.dev> In-Reply-To: <20250826011722.82391-1-youling.tang@linux.dev> References: <20250826011722.82391-1-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 Define a dedicated image header structure for LoongArch architecture to standardize kernel loading in bootloaders (primarily for kexec_file). This header includes critical metadata such as PE signature, entry points, image size and load address offset, etc. Signed-off-by: Youling Tang --- arch/loongarch/include/asm/image.h | 40 ++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 arch/loongarch/include/asm/image.h diff --git a/arch/loongarch/include/asm/image.h b/arch/loongarch/include/as= m/image.h new file mode 100644 index 000000000000..1f090736e71d --- /dev/null +++ b/arch/loongarch/include/asm/image.h @@ -0,0 +1,40 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * LoongArch binary image header. + * + * Author: Youling Tang + * Copyright (C) 2025 KylinSoft Corporation. + * + * Most code is derived from LoongArch port of kexec-tools + */ + +#ifndef __ASM_IMAGE_H +#define __ASM_IMAGE_H +#ifndef __ASSEMBLY__ + +/** + * struct loongarch_image_header + * + * @pe_sig: Optional PE format 'MZ' signature. + * @reserved_1: Reserved. + * @kernel_entry: Kernel image entry pointer. + * @image_size: An estimated size of the memory image size in LSB byte ord= er. + * @text_offset: The image load offset in LSB byte order. + * @reserved_2: Reserved. + * @reserved_3: Reserved. + * @pe_header: Optional offset to a PE format header. + **/ + +struct loongarch_image_header { + uint8_t pe_sig[2]; + uint16_t reserved_1[3]; + uint64_t kernel_entry; + uint64_t image_size; + uint64_t text_offset; + uint64_t reserved_2[3]; + uint32_t reserved_3; + uint32_t pe_header; +}; + +#endif /* __ASSEMBLY__ */ +#endif /* __ASM_IMAGE_H */ --=20 2.43.0 From nobody Fri Oct 3 20:25:01 2025 Received: from out-182.mta0.migadu.com (out-182.mta0.migadu.com [91.218.175.182]) (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 EDCA31DE4C9 for ; Tue, 26 Aug 2025 01:18:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.182 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756171102; cv=none; b=hA4/R4ZQZ9xkpkLfYdHoC72cJ+eWgVK7nwoWeVZ4UpgdQpEZrq7+ThRI8UUUXVYq37JCpthm/Q4iVFMiPJKg33Zy/f2DN4qrMMAdNFMruCfNgwV95M/LfvR9atixeVZ5IHWtSeHX4VkKKzH2WeOecnmFuC8AMid2Vv7LPpNeL4w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756171102; c=relaxed/simple; bh=9YcPro5M30ClwlasVFPnRn58uVsmckm+1CPemHt1mr0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Rrc7rySGRYPan6CPortBq3SzSebdVsBcRAcWnhHBg4rW4yO9xFAN+weSKKcZzMLYnO2xdSl9z36r1A6TTETH2glO+hB3Sg6DGc3+NZbth+CFeE2GiNIH/kKfLGG5JVUMvFYVgHMLr1Zq0iIrDjh1T0XdkXV2DXePdtBlf5NG0Yc= 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=QJ2BpsQL; arc=none smtp.client-ip=91.218.175.182 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="QJ2BpsQL" 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=1756171098; 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=k8n0mpD5ni/YyEkFMU86GC1Wq5pnpOYWoEcccjhBPjk=; b=QJ2BpsQLLxPKxxQ9Lk8OeaKuEPWwW5Ol4fb7FQire5eJqnKpxRcXfTrMr2amgpWx9BEGMd nDxW8ZJ/xsMQxRwmayZqJtJLdJStH1g2hK2+qjb4Ljma7z30+BG+UlK+8AYKxcDPzmW9Bt 0FHwyHN86aZlEir56QTHltKaAwuaVq0= 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 v3 2/6] LoongArch: Add preparatory infrastructure for kexec_file Date: Tue, 26 Aug 2025 09:17:18 +0800 Message-Id: <20250826011722.82391-3-youling.tang@linux.dev> In-Reply-To: <20250826011722.82391-1-youling.tang@linux.dev> References: <20250826011722.82391-1-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 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=3Dstart,size'. Signed-off-by: Youling Tang --- 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 | 116 +++++++++++++++++++++ 5 files changed, 161 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 =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 + select RELOCATABLE + config ARCH_SUPPORTS_CRASH_DUMP def_bool y =20 diff --git a/arch/loongarch/include/asm/kexec.h b/arch/loongarch/include/as= m/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; }; =20 +#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_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..67b9b214d212 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 obj-$(CONFIG_CRASH_DUMP) +=3D crash_dump.o =20 obj-$(CONFIG_UNWINDER_GUESS) +=3D 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 =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 */ @@ -287,9 +297,10 @@ void machine_kexec(struct kimage *image) /* We do not want to be bothered. */ 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("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"); =20 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..7fe3f182a632 --- /dev/null +++ b/arch/loongarch/kernel/machine_kexec_file.c @@ -0,0 +1,116 @@ +// 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 { + 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); +} + +/* Adds the "initrd=3Dstart,size" command line parameter to command line. = */ +static void cmdline_add_initrd(struct kimage *image, unsigned long *cmdlin= e_tmplen, + char *modified_cmdline, unsigned long initrd) +{ + int initrd_strlen; + + initrd_strlen =3D sprintf(modified_cmdline + (*cmdline_tmplen), "initrd= =3D0x%lx,0x%lx ", + initrd, image->initrd_buf_len); + *cmdline_tmplen +=3D 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 retur= n 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 =3D image->nr_segments; + char *modified_cmdline =3D NULL; + unsigned long cmdline_tmplen =3D 0; + unsigned long initrd_load_addr =3D 0; + int ret =3D 0; + + + kbuf.image =3D image; + /* not allocate anything below the kernel */ + kbuf.buf_min =3D kernel_load_addr + kernel_size; + + modified_cmdline =3D kzalloc(COMMAND_LINE_SIZE, GFP_KERNEL); + if (!modified_cmdline) + return -EINVAL; + + /* Ensure it's nul terminated */ + modified_cmdline[COMMAND_LINE_SIZE - 1] =3D '\0'; + + /* load initrd */ + if (initrd) { + kbuf.buffer =3D initrd; + kbuf.bufsz =3D initrd_len; + kbuf.mem =3D KEXEC_BUF_MEM_UNKNOWN; + kbuf.memsz =3D initrd_len; + kbuf.buf_align =3D 0; + /* within 1GB-aligned window of up to 32GB in size */ + kbuf.buf_max =3D round_down(kernel_load_addr, SZ_1G) + + (unsigned long)SZ_1G * 32; + kbuf.top_down =3D false; + + ret =3D kexec_add_buffer(&kbuf); + if (ret) + goto out_err; + initrd_load_addr =3D kbuf.mem; + + kexec_dprintk("Loaded initrd at 0x%lx bufsz=3D0x%lx memsz=3D0x%lx\n", + initrd_load_addr, kbuf.bufsz, kbuf.memsz); + + /* Add the initrd=3Dstart,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 =3D -EINVAL; + goto out_err; + } + memcpy(modified_cmdline + cmdline_tmplen, cmdline, cmdline_len); + cmdline =3D modified_cmdline; + image->arch.cmdline_ptr =3D (unsigned long)cmdline; + + return 0; + +out_err: + image->nr_segments =3D orig_segments; + kfree(modified_cmdline); + return ret; +} --=20 2.43.0 From nobody Fri Oct 3 20:25:01 2025 Received: from out-186.mta0.migadu.com (out-186.mta0.migadu.com [91.218.175.186]) (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 6E58526E6F5 for ; Tue, 26 Aug 2025 01:18:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.186 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756171105; cv=none; b=AKH1i+9+VTCBi9u3XoTq/5D0Bm5+Yz4moJORwLdChlqZJvnzRdNFuQhY/UAYqLkjH71qkbdrreEthZaLMdbzOUPi6pCkQJxfAgy4YXVHz/Z/NVuqWthtcd1px2MoNpezopTFRf/jdns7MjJ+p0tZZYtZvmOmrF+Bzm8RhJvdbXs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756171105; c=relaxed/simple; bh=hL9mltfftDdhyr3JIZVINIYCy/VR/EQG9mB/RL8BnaM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=siNx1RHqroJnkyajONde+34Sgu/WeMjfYDVhqf4Y1bsrjAB4vc1D3c7lJYKw+mlK0Tdl0R+96Ad7WtXTr61OTDiqNKO6+PhFLVJXbXXkpM/yN+UsyAa2w27s92WZ9ChvTEut/aEVlTGhB0BmwKhBPDTDSd37TIsPJKm3y7Ifni8= 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=Dut2otsU; arc=none smtp.client-ip=91.218.175.186 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="Dut2otsU" 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=1756171101; 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=7Tn3zWMTJJQP7Xzz39H0ZWx4y0PLkIqOLwrlEDbEtxA=; b=Dut2otsUWWfebnBkB4evJKtQuYlSs5lWQY0MSXZ7jLuoWaErgFC/D6MUho84Y5focio0E2 f43mIEZ98eFUx3k//6dpVZ6TLwBX2cUA1Wh0+hHD96fHklufmpftcdFxs5N2amyttaZ7lV XOnmKl8csCCiXhDs+Gco/OPJMOLKDpI= 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 v3 3/6] LoongArch/kexec_file: Support loading EFI binary file Date: Tue, 26 Aug 2025 09:17:19 +0800 Message-Id: <20250826011722.82391-4-youling.tang@linux.dev> In-Reply-To: <20250826011722.82391-1-youling.tang@linux.dev> References: <20250826011722.82391-1-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 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. 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/as= m/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; }; =20 +static const uint8_t loongarch_image_pe_sig[2] =3D {'M', 'Z'}; + +/** + * 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 ed7e3fc8571e..34799db933fb 100644 --- a/arch/loongarch/include/asm/kexec.h +++ b/arch/loongarch/include/asm/kexec.h @@ -42,6 +42,7 @@ struct kimage_arch { }; =20 #ifdef CONFIG_KEXEC_FILE +extern const struct kexec_file_ops kexec_efi_ops; =20 int arch_kimage_file_post_load_cleanup(struct kimage *image); #define arch_kimage_file_post_load_cleanup arch_kimage_file_post_load_clea= nup 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-$(CONFIG_MAGIC_SYSRQ) +=3D sysrq.o obj-$(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 +obj-$(CONFIG_KEXEC_FILE) +=3D machine_kexec_file.o kexec_efi.o obj-$(CONFIG_CRASH_DUMP) +=3D crash_dump.o =20 obj-$(CONFIG_UNWINDER_GUESS) +=3D unwind_guess.o diff --git a/arch/loongarch/kernel/kexec_efi.c b/arch/loongarch/kernel/kexe= c_efi.c new file mode 100644 index 000000000000..5e2d424548d9 --- /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_le= n) +{ + 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_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 =3D (struct loongarch_image_header *)kernel; + if (!h->image_size) + return ERR_PTR(-EINVAL); + + /* + * Load the kernel + * FIXME: Non-relocatable kernel rejected for kexec_file (require CONFIG_= RELOCATABLE) + */ + kbuf.image =3D image; + 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_min =3D 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_efi_ops =3D { + .probe =3D efi_kexec_probe, + .load =3D efi_kexec_load, +}; diff --git a/arch/loongarch/kernel/machine_kexec_file.c b/arch/loongarch/ke= rnel/machine_kexec_file.c index 7fe3f182a632..a713acf32db8 100644 --- a/arch/loongarch/kernel/machine_kexec_file.c +++ b/arch/loongarch/kernel/machine_kexec_file.c @@ -21,6 +21,7 @@ #include =20 const struct kexec_file_ops * const kexec_file_loaders[] =3D { + &kexec_efi_ops, NULL }; =20 --=20 2.43.0 From nobody Fri Oct 3 20:25:01 2025 Received: from out-180.mta0.migadu.com (out-180.mta0.migadu.com [91.218.175.180]) (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 B95DF288C1E for ; 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DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1756171103; 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=NL2qRizv3kWdFUkXtTX2dki08TzfPVi2Nl7IUnUwTHA=; b=Y+pJzeq3PnMBpz5yn+E4SwxrswzSQ90w8jmZ9KnuX0l5Zo17tT+njxnIWcg4kzIsjOEiTm 6coS3Z40k+0SpvgU6BAfnJJ8he2lxTEw93jEfMREgi/y0cJqLVn0D2mQI21rOWKFST0DLf g9Bx/vfSg0ZYvfULuteBJEDlBCo7Fc8= 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 v3 4/6] LoongArch/kexec_file: Support loading ELF binary file Date: Tue, 26 Aug 2025 09:17:20 +0800 Message-Id: <20250826011722.82391-5-youling.tang@linux.dev> In-Reply-To: <20250826011722.82391-1-youling.tang@linux.dev> References: <20250826011722.82391-1-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 creates kexec_elf_ops to load ELF binary file for kexec_file_load() syscall. However, for `kbuf->memsz` and `kbuf->buf_min`, special handling is require= d, and the generic `kexec_elf_load()` cannot be used directly. $ readelf -l vmlinux ... Type Offset VirtAddr PhysAddr FileSiz MemSiz Flags Align LOAD 0x0000000000010000 0x9000000000200000 0x9000000000200000 0x0000000002747a00 0x000000000287a0d8 RWE 0x10000 NOTE 0x0000000000000000 0x0000000000000000 0x0000000000000000 0x0000000000000000 0x0000000000000000 R 0x8 phdr->p_paddr should have been a physical address, but it is a virtual address on the current LoongArch. This will cause kexec_file to fail when loading the kernel and need to be converted to a physical address. From the above MemSiz, it can be seen that 0x287a0d8 has not been aligned. Although kexec_add_buffer() will perform PAGE_SIZE alignment on kbuf->memsz, there is still a stampeding in the loaded kernel space and initrd space. The initrd resolution failed when starting the second kernel. It can be known from the link script vmlinux.lds.S that, BSS_SECTION(0, SZ_64K, 8) . =3D ALIGN(PECOFF_SEGMENT_ALIGN); It needs to be aligned according to the SZ_64K size, so that after alignment, its size is consistent with _kernel_asize. Signed-off-by: Youling Tang --- arch/loongarch/Kconfig | 1 + arch/loongarch/include/asm/kexec.h | 1 + arch/loongarch/kernel/Makefile | 2 +- arch/loongarch/kernel/kexec_elf.c | 105 +++++++++++++++++++++ arch/loongarch/kernel/machine_kexec_file.c | 1 + 5 files changed, 109 insertions(+), 1 deletion(-) create mode 100644 arch/loongarch/kernel/kexec_elf.c diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index 490dc6eed749..bf2664ed7ce3 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -632,6 +632,7 @@ config ARCH_SELECTS_KEXEC_FILE def_bool y depends on KEXEC_FILE select HAVE_IMA_KEXEC if IMA + select KEXEC_ELF select RELOCATABLE =20 config ARCH_SUPPORTS_CRASH_DUMP diff --git a/arch/loongarch/include/asm/kexec.h b/arch/loongarch/include/as= m/kexec.h index 34799db933fb..fecfb3015abc 100644 --- a/arch/loongarch/include/asm/kexec.h +++ b/arch/loongarch/include/asm/kexec.h @@ -43,6 +43,7 @@ struct kimage_arch { =20 #ifdef CONFIG_KEXEC_FILE extern const struct kexec_file_ops kexec_efi_ops; +extern const struct kexec_file_ops kexec_elf_ops; =20 int arch_kimage_file_post_load_cleanup(struct kimage *image); #define arch_kimage_file_post_load_cleanup arch_kimage_file_post_load_clea= nup diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile index dd6183f353e6..001924877772 100644 --- a/arch/loongarch/kernel/Makefile +++ b/arch/loongarch/kernel/Makefile @@ -62,7 +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_efi.o +obj-$(CONFIG_KEXEC_FILE) +=3D machine_kexec_file.o kexec_efi.o kexec_elf.o obj-$(CONFIG_CRASH_DUMP) +=3D crash_dump.o =20 obj-$(CONFIG_UNWINDER_GUESS) +=3D unwind_guess.o diff --git a/arch/loongarch/kernel/kexec_elf.c b/arch/loongarch/kernel/kexe= c_elf.c new file mode 100644 index 000000000000..175d8d935e11 --- /dev/null +++ b/arch/loongarch/kernel/kexec_elf.c @@ -0,0 +1,105 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Load ELF vmlinux file for the kexec_file_load syscall. + * + * Author: Youling Tang + * Copyright (C) 2025 KylinSoft Corporation. + */ + +#define pr_fmt(fmt) "kexec_file(ELF): " fmt + +#include +#include +#include +#include +#include +#include + +static int loongarch_kexec_elf_load(struct kimage *image, struct elfhdr *e= hdr, + struct kexec_elf_info *elf_info, + struct kexec_buf *kbuf, + unsigned long *text_offset) +{ + int ret =3D -1; + size_t i; + + /* Read in the PT_LOAD segments. */ + for (i =3D 0; i < ehdr->e_phnum; i++) { + size_t size; + const struct elf_phdr *phdr; + + phdr =3D &elf_info->proghdrs[i]; + if (phdr->p_type !=3D PT_LOAD) + continue; + + size =3D phdr->p_filesz; + if (size > phdr->p_memsz) + size =3D phdr->p_memsz; + + kbuf->buffer =3D (void *)elf_info->buffer + phdr->p_offset; + kbuf->bufsz =3D size; + kbuf->buf_align =3D phdr->p_align; + *text_offset =3D __pa(phdr->p_paddr); + kbuf->buf_min =3D *text_offset; + kbuf->memsz =3D ALIGN(phdr->p_memsz, SZ_64K); + kbuf->mem =3D KEXEC_BUF_MEM_UNKNOWN; + ret =3D kexec_add_buffer(kbuf); + if (ret) + break; + } + + return ret; +} + +static void *elf_kexec_load(struct kimage *image, char *kernel_buf, + unsigned long kernel_len, char *initrd, + unsigned long initrd_len, char *cmdline, + unsigned long cmdline_len) +{ + int ret; + unsigned long text_offset =3D 0, kernel_segment_number; + struct elfhdr ehdr; + struct kexec_elf_info elf_info; + struct kexec_segment *kernel_segment; + struct kexec_buf kbuf; + + ret =3D kexec_build_elf_info(kernel_buf, kernel_len, &ehdr, &elf_info); + if (ret) + return ERR_PTR(ret); + + /* + * Load the kernel + * FIXME: Non-relocatable kernel rejected for kexec_file (require CONFIG_= RELOCATABLE) + */ + kbuf.image =3D image; + kbuf.buf_max =3D ULONG_MAX; + kbuf.top_down =3D false; + + kernel_segment_number =3D image->nr_segments; + + ret =3D loongarch_kexec_elf_load(image, &ehdr, &elf_info, &kbuf, &text_of= fset); + if (ret) + goto out; + + /* Load additional data */ + kernel_segment =3D &image->segment[kernel_segment_number]; + ret =3D load_other_segments(image, kernel_segment->mem, kernel_segment->m= emsz, + initrd, initrd_len, cmdline, cmdline_len); + if (ret) + goto out; + + /* Make sure the second kernel jumps to the correct "kernel_entry". */ + image->start =3D kernel_segment->mem + __pa(ehdr.e_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); + +out: + kexec_free_elf_info(&elf_info); + return ret ? ERR_PTR(ret) : NULL; +} + +const struct kexec_file_ops kexec_elf_ops =3D { + .probe =3D kexec_elf_probe, + .load =3D elf_kexec_load, +}; diff --git a/arch/loongarch/kernel/machine_kexec_file.c b/arch/loongarch/ke= rnel/machine_kexec_file.c index a713acf32db8..dc6e37457559 100644 --- a/arch/loongarch/kernel/machine_kexec_file.c +++ b/arch/loongarch/kernel/machine_kexec_file.c @@ -22,6 +22,7 @@ =20 const struct kexec_file_ops * const kexec_file_loaders[] =3D { &kexec_efi_ops, + &kexec_elf_ops, NULL }; =20 --=20 2.43.0 From nobody Fri Oct 3 20:25:01 2025 Received: from out-178.mta0.migadu.com (out-178.mta0.migadu.com [91.218.175.178]) (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 EACDC29D287 for ; Tue, 26 Aug 2025 01:18:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.178 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756171110; cv=none; b=l/WyIVpK1iIb/GPCijJkT9K5JeoSjSOLHelDjK2LrcTSZtL/K02t6TsnbSMThzcs9kbCvM6lFb4cOuFhlDb2X38VKyswHh35gJQURfwsmf4iLnHuNVEtcVaDn3QV+mX8NsdFOcwvwrmW7KUZBANioHvKA+CvTiIqwbmm9ZkjQCU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756171110; c=relaxed/simple; bh=jUmK03O6qt39sW1JXmuJ0moazBFyYhowvw8E+5VSZXY=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=hge8Z9sW0hW0IGWP7XNjmLsnSM+7/ySfbkNjtqX/7zwwEd3Bnx0Lgpo/ka3jVUkisXh3SKCPjaxCqvh3qRBoLP+wzMc5RX+Wribju+azml9fhL9sOR6LTjt6FTTk3yvoMdiPvsm44gLFTcbdSl302qq1t8u3pw6BIJHd+wMgI5c= 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=Rj8NFxmp; arc=none smtp.client-ip=91.218.175.178 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="Rj8NFxmp" 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=1756171106; 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=BC7L55YtALYXWh7kK1DKLN5HZDHjt9lPYAHgNVecOSU=; b=Rj8NFxmpIUui4P2ozpmdJ1o4SMqLQsKOVsE7P+D/oZAMBVF9Salqs9PR+QL+B+f5uJz2pQ OCKwl0JM4XIq0EaiEIz09MV2klUXNiAOpIUJB4X8XJqMZvivWxWBrNYmOq0YW4NR/UW1OX hDIGZYjo7SQ7QNa4UJLtUm6UGVgd1K0= 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 v3 5/6] LoongArch/kexec_file: Add crash dump support Date: Tue, 26 Aug 2025 09:17:21 +0800 Message-Id: <20250826011722.82391-6-youling.tang@linux.dev> In-Reply-To: <20250826011722.82391-1-youling.tang@linux.dev> References: <20250826011722.82391-1-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 Enabling crash dump (kdump) includes: - Prepare contents of ELF header of a core dump file, /proc/vmcore, using crash_prepare_elf64_headers(). - Add "elfcorehdr=3Dsize@start" to cmdline. - Add the "mem=3Dsize@start" parameter to the command line and pass it to the capture kernel. Limit the runtime memory area of the captured kernel to avoid disrupting the production kernel's runtime state. Signed-off-by: Youling Tang --- arch/loongarch/kernel/machine_kexec_file.c | 117 +++++++++++++++++++++ 1 file changed, 117 insertions(+) diff --git a/arch/loongarch/kernel/machine_kexec_file.c b/arch/loongarch/ke= rnel/machine_kexec_file.c index dc6e37457559..1d47be06549e 100644 --- a/arch/loongarch/kernel/machine_kexec_file.c +++ b/arch/loongarch/kernel/machine_kexec_file.c @@ -35,6 +35,83 @@ int arch_kimage_file_post_load_cleanup(struct kimage *im= age) return kexec_image_post_load_cleanup_default(image); } =20 +#ifdef CONFIG_CRASH_DUMP + +static int prepare_elf_headers(void **addr, unsigned long *sz) +{ + struct crash_mem *cmem; + unsigned int nr_ranges; + int ret; + u64 i; + phys_addr_t start, end; + + nr_ranges =3D 2; /* for exclusion of crashkernel region */ + for_each_mem_range(i, &start, &end) + nr_ranges++; + + cmem =3D kmalloc(struct_size(cmem, ranges, nr_ranges), GFP_KERNEL); + if (!cmem) + return -ENOMEM; + + cmem->max_nr_ranges =3D nr_ranges; + cmem->nr_ranges =3D 0; + for_each_mem_range(i, &start, &end) { + cmem->ranges[cmem->nr_ranges].start =3D start; + cmem->ranges[cmem->nr_ranges].end =3D end - 1; + cmem->nr_ranges++; + } + + /* Exclude crashkernel region */ + ret =3D crash_exclude_mem_range(cmem, crashk_res.start, crashk_res.end); + if (ret) + goto out; + + if (crashk_low_res.end) { + ret =3D crash_exclude_mem_range(cmem, crashk_low_res.start, crashk_low_r= es.end); + if (ret) + goto out; + } + + ret =3D crash_prepare_elf64_headers(cmem, true, addr, sz); + +out: + kfree(cmem); + return ret; +} + +/* Adds the "elfcorehdr=3Dsize@start" command line parameter to command li= ne. */ +static void cmdline_add_elfcorehdr(struct kimage *image, unsigned long *cm= dline_tmplen, + char *modified_cmdline, unsigned long elfcorehdr_sz) +{ + int elfcorehdr_strlen =3D 0; + + elfcorehdr_strlen =3D sprintf(modified_cmdline + (*cmdline_tmplen), "elfc= orehdr=3D0x%lx@0x%lx ", + elfcorehdr_sz, image->elf_load_addr); + *cmdline_tmplen +=3D elfcorehdr_strlen; +} + +/* + * Adds the "mem=3Dsize@start" command line parameter to command line, ind= icating the + * memory region the new kernel can use to boot into. + */ +static void cmdline_add_mem(struct kimage *image, unsigned long *cmdline_t= mplen, + char *modified_cmdline) +{ + int mem_strlen =3D 0; + + mem_strlen =3D sprintf(modified_cmdline + (*cmdline_tmplen), "mem=3D0x%ll= x@0x%llx ", + crashk_res.end - crashk_res.start + 1, crashk_res.start); + *cmdline_tmplen +=3D mem_strlen; + + if (crashk_low_res.end) { + mem_strlen =3D sprintf(modified_cmdline + (*cmdline_tmplen), "mem=3D0x%l= lx@0x%llx ", + crashk_low_res.end - crashk_low_res.start + 1, crashk_low_res.start); + *cmdline_tmplen +=3D mem_strlen; + } +} + +#endif + /* Adds the "initrd=3Dstart,size" command line parameter to command line. = */ static void cmdline_add_initrd(struct kimage *image, unsigned long *cmdlin= e_tmplen, char *modified_cmdline, unsigned long initrd) @@ -76,6 +153,46 @@ int load_other_segments(struct kimage *image, /* Ensure it's nul terminated */ modified_cmdline[COMMAND_LINE_SIZE - 1] =3D '\0'; =20 +#ifdef CONFIG_CRASH_DUMP + /* load elf core header */ + void *headers; + unsigned long headers_sz; + + if (image->type =3D=3D KEXEC_TYPE_CRASH) { + ret =3D prepare_elf_headers(&headers, &headers_sz); + if (ret) { + pr_err("Preparing elf core header failed\n"); + goto out_err; + } + + kbuf.buffer =3D headers; + kbuf.bufsz =3D headers_sz; + kbuf.mem =3D KEXEC_BUF_MEM_UNKNOWN; + kbuf.memsz =3D headers_sz; + kbuf.buf_align =3D SZ_64K; /* largest supported page size */ + kbuf.buf_max =3D ULONG_MAX; + kbuf.top_down =3D true; + + ret =3D kexec_add_buffer(&kbuf); + if (ret) { + vfree(headers); + goto out_err; + } + image->elf_headers =3D headers; + image->elf_load_addr =3D kbuf.mem; + image->elf_headers_sz =3D headers_sz; + + kexec_dprintk("Loaded elf core header at 0x%lx bufsz=3D0x%lx memsz=3D0x%= lx\n", + image->elf_load_addr, kbuf.bufsz, kbuf.memsz); + + /* Add the elfcorehdr=3Dsize@start parameter to the command line */ + cmdline_add_elfcorehdr(image, &cmdline_tmplen, modified_cmdline, headers= _sz); + + /* Add the mem=3Dsize@start parameter to the command line */ + cmdline_add_mem(image, &cmdline_tmplen, modified_cmdline); + } +#endif + /* load initrd */ if (initrd) { kbuf.buffer =3D initrd; --=20 2.43.0 From nobody Fri Oct 3 20:25:01 2025 Received: from out-182.mta0.migadu.com (out-182.mta0.migadu.com [91.218.175.182]) (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 D9C6B2C0F79 for ; 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DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1756171108; 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=cRynx6jaHBNziqdWwYMx6lpx2wd+0zdA8DgB67CZ52I=; b=iw87Lt0lI7mT7x88HPsJr9dKdTU6JbY8e+sk0e6hXsf3Hr7OADjRBZWmt9+LlsRpmlU7ex MS/u+j6nV6Pc6YM6rVSgL+DQ7CvauJk1ba18Q4AFLAxvBS4IRTWRuiZMHqqwBcXs8J+jVN H2IflfFvVO+MtB66ozFqsRHGIv4IgCg= 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 v3 6/6] LoongArch: Enable CONFIG_KEXEC_FILE Date: Tue, 26 Aug 2025 09:17:22 +0800 Message-Id: <20250826011722.82391-7-youling.tang@linux.dev> In-Reply-To: <20250826011722.82391-1-youling.tang@linux.dev> References: <20250826011722.82391-1-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 enables config KEXEC_FILE by default in the loongson3_defconfig, so that user-space tools like kexec-tools can use the same as the default interface for kexec/kdump on LoongArch. Signed-off-by: Youling Tang --- arch/loongarch/configs/loongson3_defconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/loongarch/configs/loongson3_defconfig b/arch/loongarch/co= nfigs/loongson3_defconfig index 34eaee0384c9..6cfea2f37cc0 100644 --- a/arch/loongarch/configs/loongson3_defconfig +++ b/arch/loongarch/configs/loongson3_defconfig @@ -45,6 +45,7 @@ CONFIG_EXPERT=3Dy CONFIG_KALLSYMS_ALL=3Dy CONFIG_PERF_EVENTS=3Dy CONFIG_KEXEC=3Dy +CONFIG_KEXEC_FILE=3Dy CONFIG_CRASH_DUMP=3Dy CONFIG_LOONGARCH=3Dy CONFIG_64BIT=3Dy --=20 2.43.0