diff options
| -rw-r--r-- | arch/x86/include/asm/kexec-bzimage64.h | 6 | ||||
| -rw-r--r-- | arch/x86/include/asm/kexec.h | 21 | ||||
| -rw-r--r-- | arch/x86/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/kexec-bzimage64.c | 375 | ||||
| -rw-r--r-- | arch/x86/kernel/machine_kexec_64.c | 5 | ||||
| -rw-r--r-- | include/linux/kexec.h | 2 | ||||
| -rw-r--r-- | kernel/kexec.c | 11 |
7 files changed, 415 insertions, 6 deletions
diff --git a/arch/x86/include/asm/kexec-bzimage64.h b/arch/x86/include/asm/kexec-bzimage64.h new file mode 100644 index 000000000000..d1b5d194e31d --- /dev/null +++ b/arch/x86/include/asm/kexec-bzimage64.h @@ -0,0 +1,6 @@ +#ifndef _ASM_KEXEC_BZIMAGE64_H +#define _ASM_KEXEC_BZIMAGE64_H + +extern struct kexec_file_ops kexec_bzImage64_ops; + +#endif /* _ASM_KEXE_BZIMAGE64_H */ diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h index 17483a492f18..0dfccced4edf 100644 --- a/arch/x86/include/asm/kexec.h +++ b/arch/x86/include/asm/kexec.h @@ -23,6 +23,7 @@ #include <asm/page.h> #include <asm/ptrace.h> +#include <asm/bootparam.h> /* * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return. @@ -161,6 +162,26 @@ struct kimage_arch { pmd_t *pmd; pte_t *pte; }; + +struct kexec_entry64_regs { + uint64_t rax; + uint64_t rbx; + uint64_t rcx; + uint64_t rdx; + uint64_t rsi; + uint64_t rdi; + uint64_t rsp; + uint64_t rbp; + uint64_t r8; + uint64_t r9; + uint64_t r10; + uint64_t r11; + uint64_t r12; + uint64_t r13; + uint64_t r14; + uint64_t r15; + uint64_t rip; +}; #endif typedef void crash_vmclear_fn(void); diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index bde3993624f1..b5ea75c4a4b4 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -118,4 +118,5 @@ ifeq ($(CONFIG_X86_64),y) obj-$(CONFIG_PCI_MMCONFIG) += mmconf-fam10h_64.o obj-y += vsmp_64.o + obj-$(CONFIG_KEXEC) += kexec-bzimage64.o endif diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c new file mode 100644 index 000000000000..bcedd100192f --- /dev/null +++ b/arch/x86/kernel/kexec-bzimage64.c @@ -0,0 +1,375 @@ +/* + * Kexec bzImage loader + * + * Copyright (C) 2014 Red Hat Inc. + * Authors: + * Vivek Goyal <vgoyal@redhat.com> + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + */ + +#define pr_fmt(fmt) "kexec-bzImage64: " fmt + +#include <linux/string.h> +#include <linux/printk.h> +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/kexec.h> +#include <linux/kernel.h> +#include <linux/mm.h> + +#include <asm/bootparam.h> +#include <asm/setup.h> + +/* + * Defines lowest physical address for various segments. Not sure where + * exactly these limits came from. Current bzimage64 loader in kexec-tools + * uses these so I am retaining it. It can be changed over time as we gain + * more insight. + */ +#define MIN_PURGATORY_ADDR 0x3000 +#define MIN_BOOTPARAM_ADDR 0x3000 +#define MIN_KERNEL_LOAD_ADDR 0x100000 +#define MIN_INITRD_LOAD_ADDR 0x1000000 + +/* + * This is a place holder for all boot loader specific data structure which + * gets allocated in one call but gets freed much later during cleanup + * time. Right now there is only one field but it can grow as need be. + */ +struct bzimage64_data { + /* + * Temporary buffer to hold bootparams buffer. This should be + * freed once the bootparam segment has been loaded. + */ + void *bootparams_buf; +}; + +static int setup_initrd(struct boot_params *params, + unsigned long initrd_load_addr, unsigned long initrd_len) +{ + params->hdr.ramdisk_image = initrd_load_addr & 0xffffffffUL; + params->hdr.ramdisk_size = initrd_len & 0xffffffffUL; + + params->ext_ramdisk_image = initrd_load_addr >> 32; + params->ext_ramdisk_size = initrd_len >> 32; + + return 0; +} + +static int setup_cmdline(struct boot_params *params, + unsigned long bootparams_load_addr, + unsigned long cmdline_offset, char *cmdline, + unsigned long cmdline_len) +{ + char *cmdline_ptr = ((char *)params) + cmdline_offset; + unsigned long cmdline_ptr_phys; + uint32_t cmdline_low_32, cmdline_ext_32; + + memcpy(cmdline_ptr, cmdline, cmdline_len); + cmdline_ptr[cmdline_len - 1] = '\0'; + + cmdline_ptr_phys = bootparams_load_addr + cmdline_offset; + cmdline_low_32 = cmdline_ptr_phys & 0xffffffffUL; + cmdline_ext_32 = cmdline_ptr_phys >> 32; + + params->hdr.cmd_line_ptr = cmdline_low_32; + if (cmdline_ext_32) + params->ext_cmd_line_ptr = cmdline_ext_32; + + return 0; +} + +static int setup_memory_map_entries(struct boot_params *params) +{ + unsigned int nr_e820_entries; + + nr_e820_entries = e820_saved.nr_map; + + /* TODO: Pass entries more than E820MAX in bootparams setup data */ + if (nr_e820_entries > E820MAX) + nr_e820_entries = E820MAX; + + params->e820_entries = nr_e820_entries; + memcpy(¶ms->e820_map, &e820_saved.map, + nr_e820_entries * sizeof(struct e820entry)); + + return 0; +} + +static int setup_boot_parameters(struct boot_params *params) +{ + unsigned int nr_e820_entries; + unsigned long long mem_k, start, end; + int i; + + /* Get subarch from existing bootparams */ + params->hdr.hardware_subarch = boot_params.hdr.hardware_subarch; + + /* Copying screen_info will do? */ + memcpy(¶ms->screen_info, &boot_params.screen_info, + sizeof(struct screen_info)); + + /* Fill in memsize later */ + params->screen_info.ext_mem_k = 0; + params->alt_mem_k = 0; + + /* Default APM info */ + memset(¶ms->apm_bios_info, 0, sizeof(params->apm_bios_info)); + + /* Default drive info */ + memset(¶ms->hd0_info, 0, sizeof(params->hd0_info)); + memset(¶ms->hd1_info, 0, sizeof(params->hd1_info)); + + /* Default sysdesc table */ + params->sys_desc_table.length = 0; + + setup_memory_map_entries(params); + nr_e820_entries = params->e820_entries; + + for (i = 0; i < nr_e820_entries; i++) { + if (params->e820_map[i].type != E820_RAM) + continue; + start = params->e820_map[i].addr; + end = params->e820_map[i].addr + params->e820_map[i].size - 1; + + if ((start <= 0x100000) && end > 0x100000) { + mem_k = (end >> 10) - (0x100000 >> 10); + params->screen_info.ext_mem_k = mem_k; + params->alt_mem_k = mem_k; + if (mem_k > 0xfc00) + params->screen_info.ext_mem_k = 0xfc00; /* 64M*/ + if (mem_k > 0xffffffff) + params->alt_mem_k = 0xffffffff; + } + } + + /* Setup EDD info */ + memcpy(params->eddbuf, boot_params.eddbuf, + EDDMAXNR * sizeof(struct edd_info)); + params->eddbuf_entries = boot_params.eddbuf_entries; + + memcpy(params->edd_mbr_sig_buffer, boot_params.edd_mbr_sig_buffer, + EDD_MBR_SIG_MAX * sizeof(unsigned int)); + + return 0; +} + +int bzImage64_probe(const char *buf, unsigned long len) +{ + int ret = -ENOEXEC; + struct setup_header *header; + + /* kernel should be atleast two sectors long */ + if (len < 2 * 512) { + pr_err("File is too short to be a bzImage\n"); + return ret; + } + + header = (struct setup_header *)(buf + offsetof(struct boot_params, hdr)); + if (memcmp((char *)&header->header, "HdrS", 4) != 0) { + pr_err("Not a bzImage\n"); + return ret; + } + + if (header->boot_flag != 0xAA55) { + pr_err("No x86 boot sector present\n"); + return ret; + } + + if (header->version < 0x020C) { + pr_err("Must be at least protocol version 2.12\n"); + return ret; + } + + if (!(header->loadflags & LOADED_HIGH)) { + pr_err("zImage not a bzImage\n"); + return ret; + } + + if (!(header->xloadflags & XLF_KERNEL_64)) { + pr_err("Not a bzImage64. XLF_KERNEL_64 is not set.\n"); + return ret; + } + + if (!(header->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G)) { + pr_err("XLF_CAN_BE_LOADED_ABOVE_4G is not set.\n"); + return ret; + } + + /* I've got a bzImage */ + pr_debug("It's a relocatable bzImage64\n"); + ret = 0; + + return ret; +} + +void *bzImage64_load(struct kimage *image, char *kernel, + unsigned long kernel_len, char *initrd, + unsigned long initrd_len, char *cmdline, + unsigned long cmdline_len) +{ + + struct setup_header *header; + int setup_sects, kern16_size, ret = 0; + unsigned long setup_header_size, params_cmdline_sz; + struct boot_params *params; + unsigned long bootparam_load_addr, kernel_load_addr, initrd_load_addr; + unsigned long purgatory_load_addr; + unsigned long kernel_bufsz, kernel_memsz, kernel_align; + char *kernel_buf; + struct bzimage64_data *ldata; + struct kexec_entry64_regs regs64; + void *stack; + unsigned int setup_hdr_offset = offsetof(struct boot_params, hdr); + + header = (struct setup_header *)(kernel + setup_hdr_offset); + setup_sects = header->setup_sects; + if (setup_sects == 0) + setup_sects = 4; + + kern16_size = (setup_sects + 1) * 512; + if (kernel_len < kern16_size) { + pr_err("bzImage truncated\n"); + return ERR_PTR(-ENOEXEC); + } + + if (cmdline_len > header->cmdline_size) { + pr_err("Kernel command line too long\n"); + return ERR_PTR(-EINVAL); + } + + /* + * Load purgatory. For 64bit entry point, purgatory code can be + * anywhere. + */ + ret = kexec_load_purgatory(image, MIN_PURGATORY_ADDR, ULONG_MAX, 1, + &purgatory_load_addr); + if (ret) { + pr_err("Loading purgatory failed\n"); + return ERR_PTR(ret); + } + + pr_debug("Loaded purgatory at 0x%lx\n", purgatory_load_addr); + + /* Load Bootparams and cmdline */ + params_cmdline_sz = sizeof(struct boot_params) + cmdline_len; + params = kzalloc(params_cmdline_sz, GFP_KERNEL); + if (!params) + return ERR_PTR(-ENOMEM); + + /* Copy setup header onto bootparams. Documentation/x86/boot.txt */ + setup_header_size = 0x0202 + kernel[0x0201] - setup_hdr_offset; + + /* Is there a limit on setup header size? */ + memcpy(¶ms->hdr, (kernel + setup_hdr_offset), setup_header_size); + + ret = kexec_add_buffer(image, (char *)params, params_cmdline_sz, + params_cmdline_sz, 16, MIN_BOOTPARAM_ADDR, + ULONG_MAX, 1, &bootparam_load_addr); + if (ret) + goto out_free_params; + pr_debug("Loaded boot_param and command line at 0x%lx bufsz=0x%lx memsz=0x%lx\n", + bootparam_load_addr, params_cmdline_sz, params_cmdline_sz); + + /* Load kernel */ + kernel_buf = kernel + kern16_size; + kernel_bufsz = kernel_len - kern16_size; + kernel_memsz = PAGE_ALIGN(header->init_size); + kernel_align = header->kernel_alignment; + + ret = kexec_add_buffer(image, kernel_buf, + kernel_bufsz, kernel_memsz, kernel_align, + MIN_KERNEL_LOAD_ADDR, ULONG_MAX, 1, + &kernel_load_addr); + if (ret) + goto out_free_params; + + pr_debug("Loaded 64bit kernel at 0x%lx bufsz=0x%lx memsz=0x%lx\n", + kernel_load_addr, kernel_memsz, kernel_memsz); + + /* Load initrd high */ + if (initrd) { + ret = kexec_add_buffer(image, initrd, initrd_len, initrd_len, + PAGE_SIZE, MIN_INITRD_LOAD_ADDR, + ULONG_MAX, 1, &initrd_load_addr); + if (ret) + goto out_free_params; + + pr_debug("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n", + initrd_load_addr, initrd_len, initrd_len); + + setup_initrd(params, initrd_load_addr, initrd_len); + } + + setup_cmdline(params, bootparam_load_addr, sizeof(struct boot_params), + cmdline, cmdline_len); + + /* bootloader info. Do we need a separate ID for kexec kernel loader? */ + params->hdr.type_of_loader = 0x0D << 4; + params->hdr.loadflags = 0; + + /* Setup purgatory regs for entry */ + ret = kexec_purgatory_get_set_symbol(image, "entry64_regs", ®s64, + sizeof(regs64), 1); + if (ret) + goto out_free_params; + + regs64.rbx = 0; /* Bootstrap Processor */ + regs64.rsi = bootparam_load_addr; + regs64.rip = kernel_load_addr + 0x200; + stack = kexec_purgatory_get_symbol_addr(image, "stack_end"); + if (IS_ERR(stack)) { + pr_err("Could not find address of symbol stack_end\n"); + ret = -EINVAL; + goto out_free_params; + } + + regs64.rsp = (unsigned long)stack; + ret = kexec_purgatory_get_set_symbol(image, "entry64_regs", ®s64, + sizeof(regs64), 0); + if (ret) + goto out_free_params; + + setup_boot_parameters(params); + + /* Allocate loader specific data */ + ldata = kzalloc(sizeof(struct bzimage64_data), GFP_KERNEL); + if (!ldata) { + ret = -ENOMEM; + goto out_free_params; + } + + /* + * Store pointer to params so that it could be freed after loading + * params segment has been loaded and contents have been copied + * somewhere else. + */ + ldata->bootparams_buf = params; + return ldata; + +out_free_params: + kfree(params); + return ERR_PTR(ret); +} + +/* This cleanup function is called after various segments have been loaded */ +int bzImage64_cleanup(void *loader_data) +{ + struct bzimage64_data *ldata = loader_data; + + if (!ldata) + return 0; + + kfree(ldata->bootparams_buf); + ldata->bootparams_buf = NULL; + + return 0; +} + +struct kexec_file_ops kexec_bzImage64_ops = { + .probe = bzImage64_probe, + .load = bzImage64_load, + .cleanup = bzImage64_cleanup, +}; diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c index 88404c440727..18d0f9e0b6da 100644 --- a/arch/x86/kernel/machine_kexec_64.c +++ b/arch/x86/kernel/machine_kexec_64.c @@ -23,9 +23,10 @@ #include <asm/tlbflush.h> #include <asm/mmu_context.h> #include <asm/debugreg.h> +#include <asm/kexec-bzimage64.h> static struct kexec_file_ops *kexec_file_loaders[] = { - NULL, + &kexec_bzImage64_ops, }; static void free_transition_pgtable(struct kimage *image) @@ -328,7 +329,7 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image) if (!image->fops || !image->fops->cleanup) return 0; - return image->fops->cleanup(image); + return image->fops->cleanup(image->image_loader_data); } /* diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 84f09e9eca26..9481703b0e7a 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -190,7 +190,7 @@ typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf, unsigned long kernel_len, char *initrd, unsigned long initrd_len, char *cmdline, unsigned long cmdline_len); -typedef int (kexec_cleanup_t)(struct kimage *image); +typedef int (kexec_cleanup_t)(void *loader_data); struct kexec_file_ops { kexec_probe_t *probe; diff --git a/kernel/kexec.c b/kernel/kexec.c index 669e331aa9ec..0926f2a3ed03 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -460,6 +460,14 @@ static void kimage_file_post_load_cleanup(struct kimage *image) /* See if architecture has anything to cleanup post load */ arch_kimage_file_post_load_cleanup(image); + + /* + * Above call should have called into bootloader to free up + * any data stored in kimage->image_loader_data. It should + * be ok now to free it up. + */ + kfree(image->image_loader_data); + image->image_loader_data = NULL; } /* @@ -576,7 +584,6 @@ out_free_control_pages: kimage_free_page_list(&image->control_pages); out_free_post_load_bufs: kimage_file_post_load_cleanup(image); - kfree(image->image_loader_data); out_free_image: kfree(image); return ret; @@ -900,8 +907,6 @@ static void kimage_free(struct kimage *image) /* Free the kexec control pages... */ kimage_free_page_list(&image->control_pages); - kfree(image->image_loader_data); - /* * Free up any temporary buffers allocated. This might hit if * error occurred much later after buffer allocation. |