Contributors: 48
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Vivek Goyal |
826 |
45.79% |
9 |
11.25% |
| Eric DeVolder |
366 |
20.29% |
4 |
5.00% |
| Eric W. Biedermann |
122 |
6.76% |
6 |
7.50% |
| AKASHI Takahiro |
118 |
6.54% |
4 |
5.00% |
| Thiago Jung Bauermann |
68 |
3.77% |
1 |
1.25% |
| Hidehiro Kawai |
38 |
2.11% |
1 |
1.25% |
| Lianbo Jiang |
38 |
2.11% |
4 |
5.00% |
| Sourabh Jain |
29 |
1.61% |
2 |
2.50% |
| Eduardo Pereira Habkost |
19 |
1.05% |
4 |
5.00% |
| Tom Lendacky |
15 |
0.83% |
1 |
1.25% |
| Kirill A. Shutemov |
15 |
0.83% |
1 |
1.25% |
| Ingo Molnar |
14 |
0.78% |
5 |
6.25% |
| Takao Indoh |
11 |
0.61% |
1 |
1.25% |
| OGAWA Hirofumi |
11 |
0.61% |
1 |
1.25% |
| Linus Torvalds (pre-git) |
8 |
0.44% |
1 |
1.25% |
| Don Zickus |
7 |
0.39% |
2 |
2.50% |
| Alexander Nyberg |
7 |
0.39% |
1 |
1.25% |
| Yoshihiro Yunomae |
6 |
0.33% |
1 |
1.25% |
| Mike Galbraith |
6 |
0.33% |
1 |
1.25% |
| Gustavo A. R. Silva |
6 |
0.33% |
1 |
1.25% |
| Dave Young |
6 |
0.33% |
1 |
1.25% |
| Baoquan He |
5 |
0.28% |
2 |
2.50% |
| Kairui Song |
5 |
0.28% |
1 |
1.25% |
| Toshi Kani |
5 |
0.28% |
1 |
1.25% |
| Magnus Damm |
5 |
0.28% |
1 |
1.25% |
| Julia Lawall |
4 |
0.22% |
1 |
1.25% |
| Yi Wang |
3 |
0.17% |
1 |
1.25% |
| Ashish Kalra |
3 |
0.17% |
1 |
1.25% |
| Yinghai Lu |
3 |
0.17% |
1 |
1.25% |
| Fengguang Wu |
3 |
0.17% |
1 |
1.25% |
| Fenghua Yu |
3 |
0.17% |
1 |
1.25% |
| Brijesh Singh |
3 |
0.17% |
1 |
1.25% |
| Andi Kleen |
3 |
0.17% |
1 |
1.25% |
| Jiang Liu |
3 |
0.17% |
1 |
1.25% |
| Jeremy Fitzhardinge |
3 |
0.17% |
1 |
1.25% |
| Zhang Yanfei |
2 |
0.11% |
1 |
1.25% |
| Chun-Yi Lee |
2 |
0.11% |
1 |
1.25% |
| Fernando Luis Vázquez Cao |
2 |
0.11% |
1 |
1.25% |
| Mikael Pettersson |
2 |
0.11% |
1 |
1.25% |
| Jaswinder Singh Rajput |
1 |
0.06% |
1 |
1.25% |
| Yuntao Wang |
1 |
0.06% |
1 |
1.25% |
| Lee Revell |
1 |
0.06% |
1 |
1.25% |
| Sean Christopherson |
1 |
0.06% |
1 |
1.25% |
| Christoph Hellwig |
1 |
0.06% |
1 |
1.25% |
| Paul Gortmaker |
1 |
0.06% |
1 |
1.25% |
| Glauber de Oliveira Costa |
1 |
0.06% |
1 |
1.25% |
| Miguel Botón |
1 |
0.06% |
1 |
1.25% |
| Thomas Gleixner |
1 |
0.06% |
1 |
1.25% |
| Total |
1804 |
|
80 |
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Architecture specific (i386/x86_64) functions for kexec based crash dumps.
*
* Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
*
* Copyright (C) IBM Corporation, 2004. All rights reserved.
* Copyright (C) Red Hat Inc., 2014. All rights reserved.
* Authors:
* Vivek Goyal <vgoyal@redhat.com>
*
*/
#define pr_fmt(fmt) "kexec: " fmt
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/smp.h>
#include <linux/reboot.h>
#include <linux/kexec.h>
#include <linux/delay.h>
#include <linux/elf.h>
#include <linux/elfcore.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/memblock.h>
#include <asm/bootparam.h>
#include <asm/processor.h>
#include <asm/hardirq.h>
#include <asm/nmi.h>
#include <asm/hw_irq.h>
#include <asm/apic.h>
#include <asm/e820/types.h>
#include <asm/io_apic.h>
#include <asm/hpet.h>
#include <linux/kdebug.h>
#include <asm/cpu.h>
#include <asm/reboot.h>
#include <asm/intel_pt.h>
#include <asm/crash.h>
#include <asm/cmdline.h>
#include <asm/sev.h>
/* Used while preparing memory map entries for second kernel */
struct crash_memmap_data {
struct boot_params *params;
/* Type of memory */
unsigned int type;
};
#if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC)
static void kdump_nmi_callback(int cpu, struct pt_regs *regs)
{
crash_save_cpu(regs, cpu);
/*
* Disable Intel PT to stop its logging
*/
cpu_emergency_stop_pt();
kdump_sev_callback();
disable_local_APIC();
}
void kdump_nmi_shootdown_cpus(void)
{
nmi_shootdown_cpus(kdump_nmi_callback);
disable_local_APIC();
}
/* Override the weak function in kernel/panic.c */
void crash_smp_send_stop(void)
{
static int cpus_stopped;
if (cpus_stopped)
return;
if (smp_ops.crash_stop_other_cpus)
smp_ops.crash_stop_other_cpus();
else
smp_send_stop();
cpus_stopped = 1;
}
#else
void crash_smp_send_stop(void)
{
/* There are no cpus to shootdown */
}
#endif
void native_machine_crash_shutdown(struct pt_regs *regs)
{
/* This function is only called after the system
* has panicked or is otherwise in a critical state.
* The minimum amount of code to allow a kexec'd kernel
* to run successfully needs to happen here.
*
* In practice this means shooting down the other cpus in
* an SMP system.
*/
/* The kernel is broken so disable interrupts */
local_irq_disable();
crash_smp_send_stop();
cpu_emergency_disable_virtualization();
/*
* Disable Intel PT to stop its logging
*/
cpu_emergency_stop_pt();
#ifdef CONFIG_X86_IO_APIC
/* Prevent crash_kexec() from deadlocking on ioapic_lock. */
ioapic_zap_locks();
clear_IO_APIC();
#endif
lapic_shutdown();
restore_boot_irq_mode();
#ifdef CONFIG_HPET_TIMER
hpet_disable();
#endif
/*
* Non-crash kexec calls enc_kexec_begin() while scheduling is still
* active. This allows the callback to wait until all in-flight
* shared<->private conversions are complete. In a crash scenario,
* enc_kexec_begin() gets called after all but one CPU have been shut
* down and interrupts have been disabled. This allows the callback to
* detect a race with the conversion and report it.
*/
x86_platform.guest.enc_kexec_begin();
x86_platform.guest.enc_kexec_finish();
crash_save_cpu(regs, safe_smp_processor_id());
}
#if defined(CONFIG_KEXEC_FILE) || defined(CONFIG_CRASH_HOTPLUG)
static int get_nr_ram_ranges_callback(struct resource *res, void *arg)
{
unsigned int *nr_ranges = arg;
(*nr_ranges)++;
return 0;
}
/* Gather all the required information to prepare elf headers for ram regions */
static struct crash_mem *fill_up_crash_elf_data(void)
{
unsigned int nr_ranges = 0;
struct crash_mem *cmem;
walk_system_ram_res(0, -1, &nr_ranges, get_nr_ram_ranges_callback);
if (!nr_ranges)
return NULL;
/*
* Exclusion of crash region and/or crashk_low_res may cause
* another range split. So add extra two slots here.
*/
nr_ranges += 2;
cmem = vzalloc(struct_size(cmem, ranges, nr_ranges));
if (!cmem)
return NULL;
cmem->max_nr_ranges = nr_ranges;
cmem->nr_ranges = 0;
return cmem;
}
/*
* Look for any unwanted ranges between mstart, mend and remove them. This
* might lead to split and split ranges are put in cmem->ranges[] array
*/
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, SZ_1M - 1);
if (ret)
return ret;
/* Exclude crashkernel region */
ret = crash_exclude_mem_range(cmem, crashk_res.start, crashk_res.end);
if (ret)
return ret;
if (crashk_low_res.end)
ret = crash_exclude_mem_range(cmem, crashk_low_res.start,
crashk_low_res.end);
return ret;
}
static int prepare_elf64_ram_headers_callback(struct resource *res, void *arg)
{
struct crash_mem *cmem = arg;
cmem->ranges[cmem->nr_ranges].start = res->start;
cmem->ranges[cmem->nr_ranges].end = res->end;
cmem->nr_ranges++;
return 0;
}
/* Prepare elf headers. Return addr and size */
static int prepare_elf_headers(void **addr, unsigned long *sz,
unsigned long *nr_mem_ranges)
{
struct crash_mem *cmem;
int ret;
cmem = fill_up_crash_elf_data();
if (!cmem)
return -ENOMEM;
ret = walk_system_ram_res(0, -1, cmem, prepare_elf64_ram_headers_callback);
if (ret)
goto out;
/* Exclude unwanted mem ranges */
ret = elf_header_exclude_ranges(cmem);
if (ret)
goto out;
/* Return the computed number of memory ranges, for hotplug usage */
*nr_mem_ranges = cmem->nr_ranges;
/* By default prepare 64bit headers */
ret = crash_prepare_elf64_headers(cmem, IS_ENABLED(CONFIG_X86_64), addr, sz);
out:
vfree(cmem);
return ret;
}
#endif
#ifdef CONFIG_KEXEC_FILE
static int add_e820_entry(struct boot_params *params, struct e820_entry *entry)
{
unsigned int nr_e820_entries;
nr_e820_entries = params->e820_entries;
if (nr_e820_entries >= E820_MAX_ENTRIES_ZEROPAGE)
return 1;
memcpy(¶ms->e820_table[nr_e820_entries], entry, sizeof(struct e820_entry));
params->e820_entries++;
return 0;
}
static int memmap_entry_callback(struct resource *res, void *arg)
{
struct crash_memmap_data *cmd = arg;
struct boot_params *params = cmd->params;
struct e820_entry ei;
ei.addr = res->start;
ei.size = resource_size(res);
ei.type = cmd->type;
add_e820_entry(params, &ei);
return 0;
}
static int memmap_exclude_ranges(struct kimage *image, struct crash_mem *cmem,
unsigned long long mstart,
unsigned long long mend)
{
unsigned long start, end;
cmem->ranges[0].start = mstart;
cmem->ranges[0].end = mend;
cmem->nr_ranges = 1;
/* Exclude elf header region */
start = image->elf_load_addr;
end = start + image->elf_headers_sz - 1;
return crash_exclude_mem_range(cmem, start, end);
}
/* Prepare memory map for crash dump kernel */
int crash_setup_memmap_entries(struct kimage *image, struct boot_params *params)
{
int i, ret = 0;
unsigned long flags;
struct e820_entry ei;
struct crash_memmap_data cmd;
struct crash_mem *cmem;
cmem = vzalloc(struct_size(cmem, ranges, 1));
if (!cmem)
return -ENOMEM;
memset(&cmd, 0, sizeof(struct crash_memmap_data));
cmd.params = params;
/* 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;
flags = IORESOURCE_MEM | IORESOURCE_BUSY;
walk_iomem_res_desc(IORES_DESC_ACPI_TABLES, flags, 0, -1, &cmd,
memmap_entry_callback);
/* Add ACPI Non-volatile Storage */
cmd.type = E820_TYPE_NVS;
walk_iomem_res_desc(IORES_DESC_ACPI_NV_STORAGE, flags, 0, -1, &cmd,
memmap_entry_callback);
/* Add e820 reserved ranges */
cmd.type = E820_TYPE_RESERVED;
flags = IORESOURCE_MEM;
walk_iomem_res_desc(IORES_DESC_RESERVED, flags, 0, -1, &cmd,
memmap_entry_callback);
/* Add crashk_low_res region */
if (crashk_low_res.end) {
ei.addr = crashk_low_res.start;
ei.size = resource_size(&crashk_low_res);
ei.type = E820_TYPE_RAM;
add_e820_entry(params, &ei);
}
/* Exclude some ranges from crashk_res and add rest to memmap */
ret = memmap_exclude_ranges(image, cmem, crashk_res.start, crashk_res.end);
if (ret)
goto out;
for (i = 0; i < cmem->nr_ranges; i++) {
ei.size = cmem->ranges[i].end - cmem->ranges[i].start + 1;
/* If entry is less than a page, skip it */
if (ei.size < PAGE_SIZE)
continue;
ei.addr = cmem->ranges[i].start;
ei.type = E820_TYPE_RAM;
add_e820_entry(params, &ei);
}
out:
vfree(cmem);
return ret;
}
int crash_load_segments(struct kimage *image)
{
int ret;
unsigned long pnum = 0;
struct kexec_buf kbuf = { .image = image, .buf_min = 0,
.buf_max = ULONG_MAX, .top_down = false };
/* Prepare elf headers and add a segment */
ret = prepare_elf_headers(&kbuf.buffer, &kbuf.bufsz, &pnum);
if (ret)
return ret;
image->elf_headers = kbuf.buffer;
image->elf_headers_sz = kbuf.bufsz;
kbuf.memsz = kbuf.bufsz;
#ifdef CONFIG_CRASH_HOTPLUG
/*
* The elfcorehdr segment size accounts for VMCOREINFO, kernel_map,
* maximum CPUs and maximum memory ranges.
*/
if (IS_ENABLED(CONFIG_MEMORY_HOTPLUG))
pnum = 2 + CONFIG_NR_CPUS_DEFAULT + CONFIG_CRASH_MAX_MEMORY_RANGES;
else
pnum += 2 + CONFIG_NR_CPUS_DEFAULT;
if (pnum < (unsigned long)PN_XNUM) {
kbuf.memsz = pnum * sizeof(Elf64_Phdr);
kbuf.memsz += sizeof(Elf64_Ehdr);
image->elfcorehdr_index = image->nr_segments;
/* Mark as usable to crash kernel, else crash kernel fails on boot */
image->elf_headers_sz = kbuf.memsz;
} else {
pr_err("number of Phdrs %lu exceeds max\n", pnum);
}
#endif
kbuf.buf_align = ELF_CORE_HEADER_ALIGN;
kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
ret = kexec_add_buffer(&kbuf);
if (ret)
return ret;
image->elf_load_addr = kbuf.mem;
kexec_dprintk("Loaded ELF headers at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
image->elf_load_addr, kbuf.bufsz, kbuf.memsz);
return ret;
}
#endif /* CONFIG_KEXEC_FILE */
#ifdef CONFIG_CRASH_HOTPLUG
#undef pr_fmt
#define pr_fmt(fmt) "crash hp: " fmt
int arch_crash_hotplug_support(struct kimage *image, unsigned long kexec_flags)
{
#ifdef CONFIG_KEXEC_FILE
if (image->file_mode)
return 1;
#endif
/*
* Initially, crash hotplug support for kexec_load was added
* with the KEXEC_UPDATE_ELFCOREHDR flag. Later, this
* functionality was expanded to accommodate multiple kexec
* segment updates, leading to the introduction of the
* KEXEC_CRASH_HOTPLUG_SUPPORT kexec flag bit. Consequently,
* when the kexec tool sends either of these flags, it indicates
* that the required kexec segment (elfcorehdr) is excluded from
* the SHA calculation.
*/
return (kexec_flags & KEXEC_UPDATE_ELFCOREHDR ||
kexec_flags & KEXEC_CRASH_HOTPLUG_SUPPORT);
}
unsigned int arch_crash_get_elfcorehdr_size(void)
{
unsigned int sz;
/* kernel_map, VMCOREINFO and maximum CPUs */
sz = 2 + CONFIG_NR_CPUS_DEFAULT;
if (IS_ENABLED(CONFIG_MEMORY_HOTPLUG))
sz += CONFIG_CRASH_MAX_MEMORY_RANGES;
sz *= sizeof(Elf64_Phdr);
return sz;
}
/**
* arch_crash_handle_hotplug_event() - Handle hotplug elfcorehdr changes
* @image: a pointer to kexec_crash_image
* @arg: struct memory_notify handler for memory hotplug case and
* NULL for CPU hotplug case.
*
* Prepare the new elfcorehdr and replace the existing elfcorehdr.
*/
void arch_crash_handle_hotplug_event(struct kimage *image, void *arg)
{
void *elfbuf = NULL, *old_elfcorehdr;
unsigned long nr_mem_ranges;
unsigned long mem, memsz;
unsigned long elfsz = 0;
/*
* As crash_prepare_elf64_headers() has already described all
* possible CPUs, there is no need to update the elfcorehdr
* for additional CPU changes.
*/
if ((image->file_mode || image->elfcorehdr_updated) &&
((image->hp_action == KEXEC_CRASH_HP_ADD_CPU) ||
(image->hp_action == KEXEC_CRASH_HP_REMOVE_CPU)))
return;
/*
* Create the new elfcorehdr reflecting the changes to CPU and/or
* memory resources.
*/
if (prepare_elf_headers(&elfbuf, &elfsz, &nr_mem_ranges)) {
pr_err("unable to create new elfcorehdr");
goto out;
}
/*
* Obtain address and size of the elfcorehdr segment, and
* check it against the new elfcorehdr buffer.
*/
mem = image->segment[image->elfcorehdr_index].mem;
memsz = image->segment[image->elfcorehdr_index].memsz;
if (elfsz > memsz) {
pr_err("update elfcorehdr elfsz %lu > memsz %lu",
elfsz, memsz);
goto out;
}
/*
* Copy new elfcorehdr over the old elfcorehdr at destination.
*/
old_elfcorehdr = kmap_local_page(pfn_to_page(mem >> PAGE_SHIFT));
if (!old_elfcorehdr) {
pr_err("mapping elfcorehdr segment failed\n");
goto out;
}
/*
* Temporarily invalidate the crash image while the
* elfcorehdr is updated.
*/
xchg(&kexec_crash_image, NULL);
memcpy_flushcache(old_elfcorehdr, elfbuf, elfsz);
xchg(&kexec_crash_image, image);
kunmap_local(old_elfcorehdr);
pr_debug("updated elfcorehdr\n");
out:
vfree(elfbuf);
}
#endif