diff options
author | Lianbo Jiang <lijiang@redhat.com> | 2019-11-08 17:00:26 +0800 |
---|---|---|
committer | Borislav Petkov <bp@suse.de> | 2019-11-14 18:24:43 +0100 |
commit | 7c321eb2b843bf25946100b7e2de4054f71ec068 (patch) | |
tree | 8660fda9abb2769fab5d5b5968cd41559871b68a /arch | |
parent | 6f599d84231fd27e42f4ca2a786a6641e8cddf00 (diff) |
x86/kdump: Remove the backup region handling
When the crashkernel kernel command line option is specified, the low
1M memory will always be reserved now. Therefore, it's not necessary to
create a backup region anymore and also no need to copy the contents of
the first 640k to it.
Remove all the code related to handling that backup region.
[ bp: Massage commit message. ]
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: bhe@redhat.com
Cc: Dave Young <dyoung@redhat.com>
Cc: d.hatayama@fujitsu.com
Cc: dhowells@redhat.com
Cc: ebiederm@xmission.com
Cc: horms@verge.net.au
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jürgen Gross <jgross@suse.com>
Cc: kexec@lists.infradead.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: vgoyal@redhat.com
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191108090027.11082-3-lijiang@redhat.com
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/include/asm/kexec.h | 10 | ||||
-rw-r--r-- | arch/x86/include/asm/purgatory.h | 10 | ||||
-rw-r--r-- | arch/x86/kernel/crash.c | 87 | ||||
-rw-r--r-- | arch/x86/kernel/machine_kexec_64.c | 47 | ||||
-rw-r--r-- | arch/x86/purgatory/purgatory.c | 19 |
5 files changed, 11 insertions, 162 deletions
diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h index 5e7d6b46de97..6802c59e8252 100644 --- a/arch/x86/include/asm/kexec.h +++ b/arch/x86/include/asm/kexec.h @@ -66,10 +66,6 @@ struct kimage; # define KEXEC_ARCH KEXEC_ARCH_X86_64 #endif -/* Memory to backup during crash kdump */ -#define KEXEC_BACKUP_SRC_START (0UL) -#define KEXEC_BACKUP_SRC_END (640 * 1024UL - 1) /* 640K */ - /* * This function is responsible for capturing register states if coming * via panic otherwise just fix up the ss and sp if coming via kernel @@ -154,12 +150,6 @@ struct kimage_arch { pud_t *pud; pmd_t *pmd; pte_t *pte; - /* Details of backup region */ - unsigned long backup_src_start; - unsigned long backup_src_sz; - - /* Physical address of backup segment */ - unsigned long backup_load_addr; /* Core ELF header buffer */ void *elf_headers; diff --git a/arch/x86/include/asm/purgatory.h b/arch/x86/include/asm/purgatory.h index 92c34e517da1..5528e9325049 100644 --- a/arch/x86/include/asm/purgatory.h +++ b/arch/x86/include/asm/purgatory.h @@ -6,16 +6,6 @@ #include <linux/purgatory.h> extern void purgatory(void); -/* - * These forward declarations serve two purposes: - * - * 1) Make sparse happy when checking arch/purgatory - * 2) Document that these are required to be global so the symbol - * lookup in kexec works - */ -extern unsigned long purgatory_backup_dest; -extern unsigned long purgatory_backup_src; -extern unsigned long purgatory_backup_sz; #endif /* __ASSEMBLY__ */ #endif /* _ASM_PURGATORY_H */ diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c index ff25a2ea271c..a16ec92b70f5 100644 --- a/arch/x86/kernel/crash.c +++ b/arch/x86/kernel/crash.c @@ -188,8 +188,6 @@ void native_machine_crash_shutdown(struct pt_regs *regs) #ifdef CONFIG_KEXEC_FILE -static unsigned long crash_zero_bytes; - static int get_nr_ram_ranges_callback(struct resource *res, void *arg) { unsigned int *nr_ranges = arg; @@ -232,6 +230,11 @@ static int elf_header_exclude_ranges(struct crash_mem *cmem) { int ret = 0; + /* Exclude the low 1M because it is always reserved */ + ret = crash_exclude_mem_range(cmem, 0, 1<<20); + if (ret) + return ret; + /* Exclude crashkernel region */ ret = crash_exclude_mem_range(cmem, crashk_res.start, crashk_res.end); if (ret) @@ -261,9 +264,7 @@ static int prepare_elf_headers(struct kimage *image, void **addr, unsigned long *sz) { struct crash_mem *cmem; - Elf64_Ehdr *ehdr; - Elf64_Phdr *phdr; - int ret, i; + int ret; cmem = fill_up_crash_elf_data(); if (!cmem) @@ -282,22 +283,7 @@ static int prepare_elf_headers(struct kimage *image, void **addr, /* By default prepare 64bit headers */ ret = crash_prepare_elf64_headers(cmem, IS_ENABLED(CONFIG_X86_64), addr, sz); - if (ret) - goto out; - /* - * If a range matches backup region, adjust offset to backup - * segment. - */ - ehdr = (Elf64_Ehdr *)*addr; - phdr = (Elf64_Phdr *)(ehdr + 1); - for (i = 0; i < ehdr->e_phnum; phdr++, i++) - if (phdr->p_type == PT_LOAD && - phdr->p_paddr == image->arch.backup_src_start && - phdr->p_memsz == image->arch.backup_src_sz) { - phdr->p_offset = image->arch.backup_load_addr; - break; - } out: vfree(cmem); return ret; @@ -336,19 +322,11 @@ static int memmap_exclude_ranges(struct kimage *image, struct crash_mem *cmem, unsigned long long mend) { unsigned long start, end; - int ret = 0; cmem->ranges[0].start = mstart; cmem->ranges[0].end = mend; cmem->nr_ranges = 1; - /* Exclude Backup region */ - start = image->arch.backup_load_addr; - end = start + image->arch.backup_src_sz - 1; - ret = crash_exclude_mem_range(cmem, start, end); - if (ret) - return ret; - /* Exclude elf header region */ start = image->arch.elf_load_addr; end = start + image->arch.elf_headers_sz - 1; @@ -371,11 +349,11 @@ int crash_setup_memmap_entries(struct kimage *image, struct boot_params *params) memset(&cmd, 0, sizeof(struct crash_memmap_data)); cmd.params = params; - /* Add first 640K segment */ - ei.addr = image->arch.backup_src_start; - ei.size = image->arch.backup_src_sz; - ei.type = E820_TYPE_RAM; - add_e820_entry(params, &ei); + /* Add the low 1M */ + cmd.type = E820_TYPE_RAM; + flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; + walk_iomem_res_desc(IORES_DESC_NONE, flags, 0, (1<<20)-1, &cmd, + memmap_entry_callback); /* Add ACPI tables */ cmd.type = E820_TYPE_ACPI; @@ -424,55 +402,12 @@ out: return ret; } -static int determine_backup_region(struct resource *res, void *arg) -{ - struct kimage *image = arg; - - image->arch.backup_src_start = res->start; - image->arch.backup_src_sz = resource_size(res); - - /* Expecting only one range for backup region */ - return 1; -} - int crash_load_segments(struct kimage *image) { int ret; struct kexec_buf kbuf = { .image = image, .buf_min = 0, .buf_max = ULONG_MAX, .top_down = false }; - /* - * Determine and load a segment for backup area. First 640K RAM - * region is backup source - */ - - ret = walk_system_ram_res(KEXEC_BACKUP_SRC_START, KEXEC_BACKUP_SRC_END, - image, determine_backup_region); - - /* Zero or postive return values are ok */ - if (ret < 0) - return ret; - - /* Add backup segment. */ - if (image->arch.backup_src_sz) { - kbuf.buffer = &crash_zero_bytes; - kbuf.bufsz = sizeof(crash_zero_bytes); - kbuf.memsz = image->arch.backup_src_sz; - kbuf.buf_align = PAGE_SIZE; - /* - * Ideally there is no source for backup segment. This is - * copied in purgatory after crash. Just add a zero filled - * segment for now to make sure checksum logic works fine. - */ - ret = kexec_add_buffer(&kbuf); - if (ret) - return ret; - image->arch.backup_load_addr = kbuf.mem; - pr_debug("Loaded backup region at 0x%lx backup_start=0x%lx memsz=0x%lx\n", - image->arch.backup_load_addr, - image->arch.backup_src_start, kbuf.memsz); - } - /* Prepare elf headers and add a segment */ ret = prepare_elf_headers(image, &kbuf.buffer, &kbuf.bufsz); if (ret) diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c index 5dcd438ad8f2..16e125a50b33 100644 --- a/arch/x86/kernel/machine_kexec_64.c +++ b/arch/x86/kernel/machine_kexec_64.c @@ -298,48 +298,6 @@ static void load_segments(void) ); } -#ifdef CONFIG_KEXEC_FILE -/* Update purgatory as needed after various image segments have been prepared */ -static int arch_update_purgatory(struct kimage *image) -{ - int ret = 0; - - if (!image->file_mode) - return 0; - - /* Setup copying of backup region */ - if (image->type == KEXEC_TYPE_CRASH) { - ret = kexec_purgatory_get_set_symbol(image, - "purgatory_backup_dest", - &image->arch.backup_load_addr, - sizeof(image->arch.backup_load_addr), 0); - if (ret) - return ret; - - ret = kexec_purgatory_get_set_symbol(image, - "purgatory_backup_src", - &image->arch.backup_src_start, - sizeof(image->arch.backup_src_start), 0); - if (ret) - return ret; - - ret = kexec_purgatory_get_set_symbol(image, - "purgatory_backup_sz", - &image->arch.backup_src_sz, - sizeof(image->arch.backup_src_sz), 0); - if (ret) - return ret; - } - - return ret; -} -#else /* !CONFIG_KEXEC_FILE */ -static inline int arch_update_purgatory(struct kimage *image) -{ - return 0; -} -#endif /* CONFIG_KEXEC_FILE */ - int machine_kexec_prepare(struct kimage *image) { unsigned long start_pgtable; @@ -353,11 +311,6 @@ int machine_kexec_prepare(struct kimage *image) if (result) return result; - /* update purgatory as needed */ - result = arch_update_purgatory(image); - if (result) - return result; - return 0; } diff --git a/arch/x86/purgatory/purgatory.c b/arch/x86/purgatory/purgatory.c index 3b95410ff0f8..2961234d0795 100644 --- a/arch/x86/purgatory/purgatory.c +++ b/arch/x86/purgatory/purgatory.c @@ -14,28 +14,10 @@ #include "../boot/string.h" -unsigned long purgatory_backup_dest __section(.kexec-purgatory); -unsigned long purgatory_backup_src __section(.kexec-purgatory); -unsigned long purgatory_backup_sz __section(.kexec-purgatory); - u8 purgatory_sha256_digest[SHA256_DIGEST_SIZE] __section(.kexec-purgatory); struct kexec_sha_region purgatory_sha_regions[KEXEC_SEGMENT_MAX] __section(.kexec-purgatory); -/* - * On x86, second kernel requries first 640K of memory to boot. Copy - * first 640K to a backup region in reserved memory range so that second - * kernel can use first 640K. - */ -static int copy_backup_region(void) -{ - if (purgatory_backup_dest) { - memcpy((void *)purgatory_backup_dest, - (void *)purgatory_backup_src, purgatory_backup_sz); - } - return 0; -} - static int verify_sha256_digest(void) { struct kexec_sha_region *ptr, *end; @@ -66,7 +48,6 @@ void purgatory(void) for (;;) ; } - copy_backup_region(); } /* |