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crash: split crash dumping code out from kexec_core.c
Currently, KEXEC_CORE select CRASH_CORE automatically because crash codes need be built in to avoid compiling error when building kexec code even though the crash dumping functionality is not enabled. E.g -------------------- CONFIG_CRASH_CORE=y CONFIG_KEXEC_CORE=y CONFIG_KEXEC=y CONFIG_KEXEC_FILE=y --------------------- After splitting out crashkernel reservation code and vmcoreinfo exporting code, there's only crash related code left in kernel/crash_core.c. Now move crash related codes from kexec_core.c to crash_core.c and only build it in when CONFIG_CRASH_DUMP=y. And also wrap up crash codes inside CONFIG_CRASH_DUMP ifdeffery scope, or replace inappropriate CONFIG_KEXEC_CORE ifdef with CONFIG_CRASH_DUMP ifdef in generic kernel files. With these changes, crash_core codes are abstracted from kexec codes and can be disabled at all if only kexec reboot feature is wanted. Link: https://lkml.kernel.org/r/20240124051254.67105-5-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Pingfan Liu <piliu@redhat.com> Cc: Klara Modin <klarasmodin@gmail.com> Cc: Michael Kelley <mhklinux@outlook.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Baoquan He
Andrew Morton
parent
2c44b67e2e
commit
02aff84805
@ -144,7 +144,7 @@ static DEVICE_ATTR(release, S_IWUSR, NULL, cpu_release_store);
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#endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
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#endif /* CONFIG_HOTPLUG_CPU */
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#ifdef CONFIG_KEXEC_CORE
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#ifdef CONFIG_CRASH_DUMP
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#include <linux/kexec.h>
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static ssize_t crash_notes_show(struct device *dev,
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@ -189,14 +189,14 @@ static const struct attribute_group crash_note_cpu_attr_group = {
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#endif
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static const struct attribute_group *common_cpu_attr_groups[] = {
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#ifdef CONFIG_KEXEC_CORE
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#ifdef CONFIG_CRASH_DUMP
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&crash_note_cpu_attr_group,
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#endif
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NULL
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};
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static const struct attribute_group *hotplugable_cpu_attr_groups[] = {
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#ifdef CONFIG_KEXEC_CORE
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#ifdef CONFIG_CRASH_DUMP
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&crash_note_cpu_attr_group,
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#endif
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NULL
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@ -6,6 +6,48 @@
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#include <linux/elfcore.h>
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#include <linux/elf.h>
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struct kimage;
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#ifdef CONFIG_CRASH_DUMP
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int crash_shrink_memory(unsigned long new_size);
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ssize_t crash_get_memory_size(void);
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#ifndef arch_kexec_protect_crashkres
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/*
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* Protection mechanism for crashkernel reserved memory after
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* the kdump kernel is loaded.
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*
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* Provide an empty default implementation here -- architecture
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* code may override this
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*/
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static inline void arch_kexec_protect_crashkres(void) { }
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#endif
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#ifndef arch_kexec_unprotect_crashkres
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static inline void arch_kexec_unprotect_crashkres(void) { }
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#endif
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#ifndef arch_crash_handle_hotplug_event
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static inline void arch_crash_handle_hotplug_event(struct kimage *image) { }
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#endif
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int crash_check_update_elfcorehdr(void);
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#ifndef crash_hotplug_cpu_support
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static inline int crash_hotplug_cpu_support(void) { return 0; }
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#endif
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#ifndef crash_hotplug_memory_support
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static inline int crash_hotplug_memory_support(void) { return 0; }
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#endif
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#ifndef crash_get_elfcorehdr_size
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static inline unsigned int crash_get_elfcorehdr_size(void) { return 0; }
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#endif
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/* Alignment required for elf header segment */
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#define ELF_CORE_HEADER_ALIGN 4096
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@ -31,4 +73,23 @@ struct kexec_segment;
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#define KEXEC_CRASH_HP_REMOVE_MEMORY 4
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#define KEXEC_CRASH_HP_INVALID_CPU -1U
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extern void __crash_kexec(struct pt_regs *regs);
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extern void crash_kexec(struct pt_regs *regs);
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int kexec_should_crash(struct task_struct *p);
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int kexec_crash_loaded(void);
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void crash_save_cpu(struct pt_regs *regs, int cpu);
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extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
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#else /* !CONFIG_CRASH_DUMP*/
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struct pt_regs;
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struct task_struct;
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struct kimage;
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static inline void __crash_kexec(struct pt_regs *regs) { }
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static inline void crash_kexec(struct pt_regs *regs) { }
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static inline int kexec_should_crash(struct task_struct *p) { return 0; }
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static inline int kexec_crash_loaded(void) { return 0; }
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static inline void crash_save_cpu(struct pt_regs *regs, int cpu) {};
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static inline int kimage_crash_copy_vmcoreinfo(struct kimage *image) { return 0; };
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#endif /* CONFIG_CRASH_DUMP*/
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#endif /* LINUX_CRASH_CORE_H */
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@ -15,7 +15,6 @@
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#if !defined(__ASSEMBLY__)
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#include <linux/crash_core.h>
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#include <linux/vmcore_info.h>
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#include <linux/crash_reserve.h>
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#include <asm/io.h>
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@ -33,6 +32,7 @@ extern note_buf_t __percpu *crash_notes;
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#include <linux/module.h>
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#include <linux/highmem.h>
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#include <asm/kexec.h>
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#include <linux/crash_core.h>
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/* Verify architecture specific macros are defined */
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@ -380,13 +380,6 @@ extern struct page *kimage_alloc_control_pages(struct kimage *image,
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static inline int machine_kexec_post_load(struct kimage *image) { return 0; }
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#endif
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extern void __crash_kexec(struct pt_regs *);
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extern void crash_kexec(struct pt_regs *);
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int kexec_should_crash(struct task_struct *);
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int kexec_crash_loaded(void);
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void crash_save_cpu(struct pt_regs *regs, int cpu);
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extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
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extern struct kimage *kexec_image;
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extern struct kimage *kexec_crash_image;
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@ -410,24 +403,6 @@ bool kexec_load_permitted(int kexec_image_type);
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/* flag to track if kexec reboot is in progress */
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extern bool kexec_in_progress;
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int crash_shrink_memory(unsigned long new_size);
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ssize_t crash_get_memory_size(void);
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#ifndef arch_kexec_protect_crashkres
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/*
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* Protection mechanism for crashkernel reserved memory after
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* the kdump kernel is loaded.
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*
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* Provide an empty default implementation here -- architecture
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* code may override this
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*/
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static inline void arch_kexec_protect_crashkres(void) { }
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#endif
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#ifndef arch_kexec_unprotect_crashkres
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static inline void arch_kexec_unprotect_crashkres(void) { }
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#endif
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#ifndef page_to_boot_pfn
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static inline unsigned long page_to_boot_pfn(struct page *page)
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{
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@ -484,24 +459,6 @@ static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, g
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static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
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#endif
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#ifndef arch_crash_handle_hotplug_event
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static inline void arch_crash_handle_hotplug_event(struct kimage *image) { }
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#endif
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int crash_check_update_elfcorehdr(void);
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#ifndef crash_hotplug_cpu_support
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static inline int crash_hotplug_cpu_support(void) { return 0; }
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#endif
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#ifndef crash_hotplug_memory_support
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static inline int crash_hotplug_memory_support(void) { return 0; }
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#endif
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#ifndef crash_get_elfcorehdr_size
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static inline unsigned int crash_get_elfcorehdr_size(void) { return 0; }
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#endif
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extern bool kexec_file_dbg_print;
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#define kexec_dprintk(fmt, ...) \
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@ -642,7 +642,7 @@ void __weak __init free_initrd_mem(unsigned long start, unsigned long end)
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"initrd");
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}
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#ifdef CONFIG_KEXEC_CORE
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#ifdef CONFIG_CRASH_RESERVE
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static bool __init kexec_free_initrd(void)
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{
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unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
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@ -70,7 +70,8 @@ obj-$(CONFIG_KALLSYMS_SELFTEST) += kallsyms_selftest.o
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obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
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obj-$(CONFIG_VMCORE_INFO) += vmcore_info.o elfcorehdr.o
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obj-$(CONFIG_CRASH_RESERVE) += crash_reserve.o
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obj-$(CONFIG_KEXEC_CORE) += kexec_core.o crash_core.o
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obj-$(CONFIG_KEXEC_CORE) += kexec_core.o
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obj-$(CONFIG_CRASH_DUMP) += crash_core.o
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obj-$(CONFIG_KEXEC) += kexec.o
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obj-$(CONFIG_KEXEC_FILE) += kexec_file.o
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obj-$(CONFIG_KEXEC_ELF) += kexec_elf.o
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@ -11,9 +11,14 @@
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#include <linux/sizes.h>
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#include <linux/kexec.h>
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#include <linux/memory.h>
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#include <linux/mm.h>
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#include <linux/cpuhotplug.h>
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#include <linux/memblock.h>
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#include <linux/kmemleak.h>
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#include <linux/crash_core.h>
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#include <linux/reboot.h>
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#include <linux/btf.h>
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#include <linux/objtool.h>
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#include <asm/page.h>
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#include <asm/sections.h>
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@ -26,6 +31,131 @@
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/* Per cpu memory for storing cpu states in case of system crash. */
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note_buf_t __percpu *crash_notes;
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#ifdef CONFIG_CRASH_DUMP
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int kimage_crash_copy_vmcoreinfo(struct kimage *image)
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{
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struct page *vmcoreinfo_page;
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void *safecopy;
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if (!IS_ENABLED(CONFIG_CRASH_DUMP))
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return 0;
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if (image->type != KEXEC_TYPE_CRASH)
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return 0;
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/*
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* For kdump, allocate one vmcoreinfo safe copy from the
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* crash memory. as we have arch_kexec_protect_crashkres()
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* after kexec syscall, we naturally protect it from write
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* (even read) access under kernel direct mapping. But on
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* the other hand, we still need to operate it when crash
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* happens to generate vmcoreinfo note, hereby we rely on
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* vmap for this purpose.
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*/
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vmcoreinfo_page = kimage_alloc_control_pages(image, 0);
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if (!vmcoreinfo_page) {
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pr_warn("Could not allocate vmcoreinfo buffer\n");
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return -ENOMEM;
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}
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safecopy = vmap(&vmcoreinfo_page, 1, VM_MAP, PAGE_KERNEL);
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if (!safecopy) {
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pr_warn("Could not vmap vmcoreinfo buffer\n");
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return -ENOMEM;
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}
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image->vmcoreinfo_data_copy = safecopy;
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crash_update_vmcoreinfo_safecopy(safecopy);
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return 0;
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}
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int kexec_should_crash(struct task_struct *p)
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{
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/*
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* If crash_kexec_post_notifiers is enabled, don't run
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* crash_kexec() here yet, which must be run after panic
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* notifiers in panic().
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*/
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if (crash_kexec_post_notifiers)
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return 0;
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/*
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* There are 4 panic() calls in make_task_dead() path, each of which
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* corresponds to each of these 4 conditions.
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*/
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if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops)
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return 1;
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return 0;
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}
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int kexec_crash_loaded(void)
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{
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return !!kexec_crash_image;
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}
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EXPORT_SYMBOL_GPL(kexec_crash_loaded);
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/*
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* No panic_cpu check version of crash_kexec(). This function is called
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* only when panic_cpu holds the current CPU number; this is the only CPU
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* which processes crash_kexec routines.
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*/
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void __noclone __crash_kexec(struct pt_regs *regs)
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{
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/* Take the kexec_lock here to prevent sys_kexec_load
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* running on one cpu from replacing the crash kernel
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* we are using after a panic on a different cpu.
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*
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* If the crash kernel was not located in a fixed area
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* of memory the xchg(&kexec_crash_image) would be
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* sufficient. But since I reuse the memory...
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*/
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if (kexec_trylock()) {
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if (kexec_crash_image) {
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struct pt_regs fixed_regs;
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crash_setup_regs(&fixed_regs, regs);
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crash_save_vmcoreinfo();
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machine_crash_shutdown(&fixed_regs);
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machine_kexec(kexec_crash_image);
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}
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kexec_unlock();
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}
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}
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STACK_FRAME_NON_STANDARD(__crash_kexec);
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__bpf_kfunc void crash_kexec(struct pt_regs *regs)
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{
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int old_cpu, this_cpu;
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/*
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* Only one CPU is allowed to execute the crash_kexec() code as with
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* panic(). Otherwise parallel calls of panic() and crash_kexec()
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* may stop each other. To exclude them, we use panic_cpu here too.
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*/
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old_cpu = PANIC_CPU_INVALID;
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this_cpu = raw_smp_processor_id();
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if (atomic_try_cmpxchg(&panic_cpu, &old_cpu, this_cpu)) {
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/* This is the 1st CPU which comes here, so go ahead. */
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__crash_kexec(regs);
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/*
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* Reset panic_cpu to allow another panic()/crash_kexec()
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* call.
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*/
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atomic_set(&panic_cpu, PANIC_CPU_INVALID);
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}
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}
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static inline resource_size_t crash_resource_size(const struct resource *res)
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{
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return !res->end ? 0 : resource_size(res);
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}
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int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
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void **addr, unsigned long *sz)
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{
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@ -187,6 +317,130 @@ int crash_exclude_mem_range(struct crash_mem *mem,
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return 0;
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}
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ssize_t crash_get_memory_size(void)
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{
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ssize_t size = 0;
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if (!kexec_trylock())
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return -EBUSY;
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size += crash_resource_size(&crashk_res);
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size += crash_resource_size(&crashk_low_res);
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kexec_unlock();
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return size;
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}
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static int __crash_shrink_memory(struct resource *old_res,
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unsigned long new_size)
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{
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struct resource *ram_res;
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ram_res = kzalloc(sizeof(*ram_res), GFP_KERNEL);
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if (!ram_res)
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return -ENOMEM;
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ram_res->start = old_res->start + new_size;
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ram_res->end = old_res->end;
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ram_res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
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ram_res->name = "System RAM";
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if (!new_size) {
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release_resource(old_res);
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old_res->start = 0;
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old_res->end = 0;
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} else {
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crashk_res.end = ram_res->start - 1;
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}
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crash_free_reserved_phys_range(ram_res->start, ram_res->end);
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insert_resource(&iomem_resource, ram_res);
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return 0;
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}
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int crash_shrink_memory(unsigned long new_size)
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{
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int ret = 0;
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unsigned long old_size, low_size;
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if (!kexec_trylock())
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return -EBUSY;
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if (kexec_crash_image) {
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ret = -ENOENT;
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goto unlock;
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}
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low_size = crash_resource_size(&crashk_low_res);
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old_size = crash_resource_size(&crashk_res) + low_size;
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new_size = roundup(new_size, KEXEC_CRASH_MEM_ALIGN);
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if (new_size >= old_size) {
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ret = (new_size == old_size) ? 0 : -EINVAL;
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goto unlock;
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}
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/*
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* (low_size > new_size) implies that low_size is greater than zero.
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* This also means that if low_size is zero, the else branch is taken.
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*
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* If low_size is greater than 0, (low_size > new_size) indicates that
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* crashk_low_res also needs to be shrunken. Otherwise, only crashk_res
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* needs to be shrunken.
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*/
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if (low_size > new_size) {
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ret = __crash_shrink_memory(&crashk_res, 0);
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if (ret)
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goto unlock;
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ret = __crash_shrink_memory(&crashk_low_res, new_size);
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} else {
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ret = __crash_shrink_memory(&crashk_res, new_size - low_size);
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}
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/* Swap crashk_res and crashk_low_res if needed */
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if (!crashk_res.end && crashk_low_res.end) {
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||||
crashk_res.start = crashk_low_res.start;
|
||||
crashk_res.end = crashk_low_res.end;
|
||||
release_resource(&crashk_low_res);
|
||||
crashk_low_res.start = 0;
|
||||
crashk_low_res.end = 0;
|
||||
insert_resource(&iomem_resource, &crashk_res);
|
||||
}
|
||||
|
||||
unlock:
|
||||
kexec_unlock();
|
||||
return ret;
|
||||
}
|
||||
|
||||
void crash_save_cpu(struct pt_regs *regs, int cpu)
|
||||
{
|
||||
struct elf_prstatus prstatus;
|
||||
u32 *buf;
|
||||
|
||||
if ((cpu < 0) || (cpu >= nr_cpu_ids))
|
||||
return;
|
||||
|
||||
/* Using ELF notes here is opportunistic.
|
||||
* I need a well defined structure format
|
||||
* for the data I pass, and I need tags
|
||||
* on the data to indicate what information I have
|
||||
* squirrelled away. ELF notes happen to provide
|
||||
* all of that, so there is no need to invent something new.
|
||||
*/
|
||||
buf = (u32 *)per_cpu_ptr(crash_notes, cpu);
|
||||
if (!buf)
|
||||
return;
|
||||
memset(&prstatus, 0, sizeof(prstatus));
|
||||
prstatus.common.pr_pid = current->pid;
|
||||
elf_core_copy_regs(&prstatus.pr_reg, regs);
|
||||
buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS,
|
||||
&prstatus, sizeof(prstatus));
|
||||
final_note(buf);
|
||||
}
|
||||
|
||||
|
||||
|
||||
static int __init crash_notes_memory_init(void)
|
||||
{
|
||||
/* Allocate memory for saving cpu registers. */
|
||||
@ -220,6 +474,8 @@ static int __init crash_notes_memory_init(void)
|
||||
}
|
||||
subsys_initcall(crash_notes_memory_init);
|
||||
|
||||
#endif /*CONFIG_CRASH_DUMP*/
|
||||
|
||||
#ifdef CONFIG_CRASH_HOTPLUG
|
||||
#undef pr_fmt
|
||||
#define pr_fmt(fmt) "crash hp: " fmt
|
||||
|
||||
@ -28,12 +28,14 @@ static int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
|
||||
struct kimage *image;
|
||||
bool kexec_on_panic = flags & KEXEC_ON_CRASH;
|
||||
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
if (kexec_on_panic) {
|
||||
/* Verify we have a valid entry point */
|
||||
if ((entry < phys_to_boot_phys(crashk_res.start)) ||
|
||||
(entry > phys_to_boot_phys(crashk_res.end)))
|
||||
return -EADDRNOTAVAIL;
|
||||
}
|
||||
#endif
|
||||
|
||||
/* Allocate and initialize a controlling structure */
|
||||
image = do_kimage_alloc_init();
|
||||
@ -44,11 +46,13 @@ static int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
|
||||
image->nr_segments = nr_segments;
|
||||
memcpy(image->segment, segments, nr_segments * sizeof(*segments));
|
||||
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
if (kexec_on_panic) {
|
||||
/* Enable special crash kernel control page alloc policy. */
|
||||
image->control_page = crashk_res.start;
|
||||
image->type = KEXEC_TYPE_CRASH;
|
||||
}
|
||||
#endif
|
||||
|
||||
ret = sanity_check_segment_list(image);
|
||||
if (ret)
|
||||
@ -99,13 +103,14 @@ static int do_kexec_load(unsigned long entry, unsigned long nr_segments,
|
||||
if (!kexec_trylock())
|
||||
return -EBUSY;
|
||||
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
if (flags & KEXEC_ON_CRASH) {
|
||||
dest_image = &kexec_crash_image;
|
||||
if (kexec_crash_image)
|
||||
arch_kexec_unprotect_crashkres();
|
||||
} else {
|
||||
} else
|
||||
#endif
|
||||
dest_image = &kexec_image;
|
||||
}
|
||||
|
||||
if (nr_segments == 0) {
|
||||
/* Uninstall image */
|
||||
@ -162,8 +167,10 @@ static int do_kexec_load(unsigned long entry, unsigned long nr_segments,
|
||||
image = xchg(dest_image, image);
|
||||
|
||||
out:
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
if ((flags & KEXEC_ON_CRASH) && kexec_crash_image)
|
||||
arch_kexec_protect_crashkres();
|
||||
#endif
|
||||
|
||||
kimage_free(image);
|
||||
out_unlock:
|
||||
|
||||
@ -54,30 +54,6 @@ bool kexec_in_progress = false;
|
||||
|
||||
bool kexec_file_dbg_print;
|
||||
|
||||
int kexec_should_crash(struct task_struct *p)
|
||||
{
|
||||
/*
|
||||
* If crash_kexec_post_notifiers is enabled, don't run
|
||||
* crash_kexec() here yet, which must be run after panic
|
||||
* notifiers in panic().
|
||||
*/
|
||||
if (crash_kexec_post_notifiers)
|
||||
return 0;
|
||||
/*
|
||||
* There are 4 panic() calls in make_task_dead() path, each of which
|
||||
* corresponds to each of these 4 conditions.
|
||||
*/
|
||||
if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops)
|
||||
return 1;
|
||||
return 0;
|
||||
}
|
||||
|
||||
int kexec_crash_loaded(void)
|
||||
{
|
||||
return !!kexec_crash_image;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(kexec_crash_loaded);
|
||||
|
||||
/*
|
||||
* When kexec transitions to the new kernel there is a one-to-one
|
||||
* mapping between physical and virtual addresses. On processors
|
||||
@ -209,6 +185,7 @@ int sanity_check_segment_list(struct kimage *image)
|
||||
if (total_pages > nr_pages / 2)
|
||||
return -EINVAL;
|
||||
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
/*
|
||||
* Verify we have good destination addresses. Normally
|
||||
* the caller is responsible for making certain we don't
|
||||
@ -231,6 +208,7 @@ int sanity_check_segment_list(struct kimage *image)
|
||||
return -EADDRNOTAVAIL;
|
||||
}
|
||||
}
|
||||
#endif
|
||||
|
||||
return 0;
|
||||
}
|
||||
@ -403,6 +381,7 @@ static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
|
||||
return pages;
|
||||
}
|
||||
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
static struct page *kimage_alloc_crash_control_pages(struct kimage *image,
|
||||
unsigned int order)
|
||||
{
|
||||
@ -468,6 +447,7 @@ static struct page *kimage_alloc_crash_control_pages(struct kimage *image,
|
||||
|
||||
return pages;
|
||||
}
|
||||
#endif
|
||||
|
||||
|
||||
struct page *kimage_alloc_control_pages(struct kimage *image,
|
||||
@ -479,48 +459,16 @@ struct page *kimage_alloc_control_pages(struct kimage *image,
|
||||
case KEXEC_TYPE_DEFAULT:
|
||||
pages = kimage_alloc_normal_control_pages(image, order);
|
||||
break;
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
case KEXEC_TYPE_CRASH:
|
||||
pages = kimage_alloc_crash_control_pages(image, order);
|
||||
break;
|
||||
#endif
|
||||
}
|
||||
|
||||
return pages;
|
||||
}
|
||||
|
||||
int kimage_crash_copy_vmcoreinfo(struct kimage *image)
|
||||
{
|
||||
struct page *vmcoreinfo_page;
|
||||
void *safecopy;
|
||||
|
||||
if (image->type != KEXEC_TYPE_CRASH)
|
||||
return 0;
|
||||
|
||||
/*
|
||||
* For kdump, allocate one vmcoreinfo safe copy from the
|
||||
* crash memory. as we have arch_kexec_protect_crashkres()
|
||||
* after kexec syscall, we naturally protect it from write
|
||||
* (even read) access under kernel direct mapping. But on
|
||||
* the other hand, we still need to operate it when crash
|
||||
* happens to generate vmcoreinfo note, hereby we rely on
|
||||
* vmap for this purpose.
|
||||
*/
|
||||
vmcoreinfo_page = kimage_alloc_control_pages(image, 0);
|
||||
if (!vmcoreinfo_page) {
|
||||
pr_warn("Could not allocate vmcoreinfo buffer\n");
|
||||
return -ENOMEM;
|
||||
}
|
||||
safecopy = vmap(&vmcoreinfo_page, 1, VM_MAP, PAGE_KERNEL);
|
||||
if (!safecopy) {
|
||||
pr_warn("Could not vmap vmcoreinfo buffer\n");
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
image->vmcoreinfo_data_copy = safecopy;
|
||||
crash_update_vmcoreinfo_safecopy(safecopy);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int kimage_add_entry(struct kimage *image, kimage_entry_t entry)
|
||||
{
|
||||
if (*image->entry != 0)
|
||||
@ -603,10 +551,12 @@ void kimage_free(struct kimage *image)
|
||||
if (!image)
|
||||
return;
|
||||
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
if (image->vmcoreinfo_data_copy) {
|
||||
crash_update_vmcoreinfo_safecopy(NULL);
|
||||
vunmap(image->vmcoreinfo_data_copy);
|
||||
}
|
||||
#endif
|
||||
|
||||
kimage_free_extra_pages(image);
|
||||
for_each_kimage_entry(image, ptr, entry) {
|
||||
@ -824,6 +774,7 @@ out:
|
||||
return result;
|
||||
}
|
||||
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
static int kimage_load_crash_segment(struct kimage *image,
|
||||
struct kexec_segment *segment)
|
||||
{
|
||||
@ -891,6 +842,7 @@ static int kimage_load_crash_segment(struct kimage *image,
|
||||
out:
|
||||
return result;
|
||||
}
|
||||
#endif
|
||||
|
||||
int kimage_load_segment(struct kimage *image,
|
||||
struct kexec_segment *segment)
|
||||
@ -901,9 +853,11 @@ int kimage_load_segment(struct kimage *image,
|
||||
case KEXEC_TYPE_DEFAULT:
|
||||
result = kimage_load_normal_segment(image, segment);
|
||||
break;
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
case KEXEC_TYPE_CRASH:
|
||||
result = kimage_load_crash_segment(image, segment);
|
||||
break;
|
||||
#endif
|
||||
}
|
||||
|
||||
return result;
|
||||
@ -1027,186 +981,6 @@ bool kexec_load_permitted(int kexec_image_type)
|
||||
return true;
|
||||
}
|
||||
|
||||
/*
|
||||
* No panic_cpu check version of crash_kexec(). This function is called
|
||||
* only when panic_cpu holds the current CPU number; this is the only CPU
|
||||
* which processes crash_kexec routines.
|
||||
*/
|
||||
void __noclone __crash_kexec(struct pt_regs *regs)
|
||||
{
|
||||
/* Take the kexec_lock here to prevent sys_kexec_load
|
||||
* running on one cpu from replacing the crash kernel
|
||||
* we are using after a panic on a different cpu.
|
||||
*
|
||||
* If the crash kernel was not located in a fixed area
|
||||
* of memory the xchg(&kexec_crash_image) would be
|
||||
* sufficient. But since I reuse the memory...
|
||||
*/
|
||||
if (kexec_trylock()) {
|
||||
if (kexec_crash_image) {
|
||||
struct pt_regs fixed_regs;
|
||||
|
||||
crash_setup_regs(&fixed_regs, regs);
|
||||
crash_save_vmcoreinfo();
|
||||
machine_crash_shutdown(&fixed_regs);
|
||||
machine_kexec(kexec_crash_image);
|
||||
}
|
||||
kexec_unlock();
|
||||
}
|
||||
}
|
||||
STACK_FRAME_NON_STANDARD(__crash_kexec);
|
||||
|
||||
__bpf_kfunc void crash_kexec(struct pt_regs *regs)
|
||||
{
|
||||
int old_cpu, this_cpu;
|
||||
|
||||
/*
|
||||
* Only one CPU is allowed to execute the crash_kexec() code as with
|
||||
* panic(). Otherwise parallel calls of panic() and crash_kexec()
|
||||
* may stop each other. To exclude them, we use panic_cpu here too.
|
||||
*/
|
||||
old_cpu = PANIC_CPU_INVALID;
|
||||
this_cpu = raw_smp_processor_id();
|
||||
|
||||
if (atomic_try_cmpxchg(&panic_cpu, &old_cpu, this_cpu)) {
|
||||
/* This is the 1st CPU which comes here, so go ahead. */
|
||||
__crash_kexec(regs);
|
||||
|
||||
/*
|
||||
* Reset panic_cpu to allow another panic()/crash_kexec()
|
||||
* call.
|
||||
*/
|
||||
atomic_set(&panic_cpu, PANIC_CPU_INVALID);
|
||||
}
|
||||
}
|
||||
|
||||
static inline resource_size_t crash_resource_size(const struct resource *res)
|
||||
{
|
||||
return !res->end ? 0 : resource_size(res);
|
||||
}
|
||||
|
||||
ssize_t crash_get_memory_size(void)
|
||||
{
|
||||
ssize_t size = 0;
|
||||
|
||||
if (!kexec_trylock())
|
||||
return -EBUSY;
|
||||
|
||||
size += crash_resource_size(&crashk_res);
|
||||
size += crash_resource_size(&crashk_low_res);
|
||||
|
||||
kexec_unlock();
|
||||
return size;
|
||||
}
|
||||
|
||||
static int __crash_shrink_memory(struct resource *old_res,
|
||||
unsigned long new_size)
|
||||
{
|
||||
struct resource *ram_res;
|
||||
|
||||
ram_res = kzalloc(sizeof(*ram_res), GFP_KERNEL);
|
||||
if (!ram_res)
|
||||
return -ENOMEM;
|
||||
|
||||
ram_res->start = old_res->start + new_size;
|
||||
ram_res->end = old_res->end;
|
||||
ram_res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
|
||||
ram_res->name = "System RAM";
|
||||
|
||||
if (!new_size) {
|
||||
release_resource(old_res);
|
||||
old_res->start = 0;
|
||||
old_res->end = 0;
|
||||
} else {
|
||||
crashk_res.end = ram_res->start - 1;
|
||||
}
|
||||
|
||||
crash_free_reserved_phys_range(ram_res->start, ram_res->end);
|
||||
insert_resource(&iomem_resource, ram_res);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
int crash_shrink_memory(unsigned long new_size)
|
||||
{
|
||||
int ret = 0;
|
||||
unsigned long old_size, low_size;
|
||||
|
||||
if (!kexec_trylock())
|
||||
return -EBUSY;
|
||||
|
||||
if (kexec_crash_image) {
|
||||
ret = -ENOENT;
|
||||
goto unlock;
|
||||
}
|
||||
|
||||
low_size = crash_resource_size(&crashk_low_res);
|
||||
old_size = crash_resource_size(&crashk_res) + low_size;
|
||||
new_size = roundup(new_size, KEXEC_CRASH_MEM_ALIGN);
|
||||
if (new_size >= old_size) {
|
||||
ret = (new_size == old_size) ? 0 : -EINVAL;
|
||||
goto unlock;
|
||||
}
|
||||
|
||||
/*
|
||||
* (low_size > new_size) implies that low_size is greater than zero.
|
||||
* This also means that if low_size is zero, the else branch is taken.
|
||||
*
|
||||
* If low_size is greater than 0, (low_size > new_size) indicates that
|
||||
* crashk_low_res also needs to be shrunken. Otherwise, only crashk_res
|
||||
* needs to be shrunken.
|
||||
*/
|
||||
if (low_size > new_size) {
|
||||
ret = __crash_shrink_memory(&crashk_res, 0);
|
||||
if (ret)
|
||||
goto unlock;
|
||||
|
||||
ret = __crash_shrink_memory(&crashk_low_res, new_size);
|
||||
} else {
|
||||
ret = __crash_shrink_memory(&crashk_res, new_size - low_size);
|
||||
}
|
||||
|
||||
/* Swap crashk_res and crashk_low_res if needed */
|
||||
if (!crashk_res.end && crashk_low_res.end) {
|
||||
crashk_res.start = crashk_low_res.start;
|
||||
crashk_res.end = crashk_low_res.end;
|
||||
release_resource(&crashk_low_res);
|
||||
crashk_low_res.start = 0;
|
||||
crashk_low_res.end = 0;
|
||||
insert_resource(&iomem_resource, &crashk_res);
|
||||
}
|
||||
|
||||
unlock:
|
||||
kexec_unlock();
|
||||
return ret;
|
||||
}
|
||||
|
||||
void crash_save_cpu(struct pt_regs *regs, int cpu)
|
||||
{
|
||||
struct elf_prstatus prstatus;
|
||||
u32 *buf;
|
||||
|
||||
if ((cpu < 0) || (cpu >= nr_cpu_ids))
|
||||
return;
|
||||
|
||||
/* Using ELF notes here is opportunistic.
|
||||
* I need a well defined structure format
|
||||
* for the data I pass, and I need tags
|
||||
* on the data to indicate what information I have
|
||||
* squirrelled away. ELF notes happen to provide
|
||||
* all of that, so there is no need to invent something new.
|
||||
*/
|
||||
buf = (u32 *)per_cpu_ptr(crash_notes, cpu);
|
||||
if (!buf)
|
||||
return;
|
||||
memset(&prstatus, 0, sizeof(prstatus));
|
||||
prstatus.common.pr_pid = current->pid;
|
||||
elf_core_copy_regs(&prstatus.pr_reg, regs);
|
||||
buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS,
|
||||
&prstatus, sizeof(prstatus));
|
||||
final_note(buf);
|
||||
}
|
||||
|
||||
/*
|
||||
* Move into place and start executing a preloaded standalone
|
||||
* executable. If nothing was preloaded return an error.
|
||||
|
||||
@ -285,11 +285,13 @@ kimage_file_alloc_init(struct kimage **rimage, int kernel_fd,
|
||||
kexec_file_dbg_print = !!(flags & KEXEC_FILE_DEBUG);
|
||||
image->file_mode = 1;
|
||||
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
if (kexec_on_panic) {
|
||||
/* Enable special crash kernel control page alloc policy. */
|
||||
image->control_page = crashk_res.start;
|
||||
image->type = KEXEC_TYPE_CRASH;
|
||||
}
|
||||
#endif
|
||||
|
||||
ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd,
|
||||
cmdline_ptr, cmdline_len, flags);
|
||||
@ -349,13 +351,14 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
|
||||
if (!kexec_trylock())
|
||||
return -EBUSY;
|
||||
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
if (image_type == KEXEC_TYPE_CRASH) {
|
||||
dest_image = &kexec_crash_image;
|
||||
if (kexec_crash_image)
|
||||
arch_kexec_unprotect_crashkres();
|
||||
} else {
|
||||
} else
|
||||
#endif
|
||||
dest_image = &kexec_image;
|
||||
}
|
||||
|
||||
if (flags & KEXEC_FILE_UNLOAD)
|
||||
goto exchange;
|
||||
@ -419,8 +422,10 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
|
||||
exchange:
|
||||
image = xchg(dest_image, image);
|
||||
out:
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
if ((flags & KEXEC_FILE_ON_CRASH) && kexec_crash_image)
|
||||
arch_kexec_protect_crashkres();
|
||||
#endif
|
||||
|
||||
kexec_unlock();
|
||||
kimage_free(image);
|
||||
@ -595,12 +600,14 @@ static int kexec_walk_memblock(struct kexec_buf *kbuf,
|
||||
static int kexec_walk_resources(struct kexec_buf *kbuf,
|
||||
int (*func)(struct resource *, void *))
|
||||
{
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
if (kbuf->image->type == KEXEC_TYPE_CRASH)
|
||||
return walk_iomem_res_desc(crashk_res.desc,
|
||||
IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
|
||||
crashk_res.start, crashk_res.end,
|
||||
kbuf, func);
|
||||
else if (kbuf->top_down)
|
||||
#endif
|
||||
if (kbuf->top_down)
|
||||
return walk_system_ram_res_rev(0, ULONG_MAX, kbuf, func);
|
||||
else
|
||||
return walk_system_ram_res(0, ULONG_MAX, kbuf, func);
|
||||
|
||||
@ -120,6 +120,7 @@ static ssize_t kexec_loaded_show(struct kobject *kobj,
|
||||
}
|
||||
KERNEL_ATTR_RO(kexec_loaded);
|
||||
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
static ssize_t kexec_crash_loaded_show(struct kobject *kobj,
|
||||
struct kobj_attribute *attr, char *buf)
|
||||
{
|
||||
@ -152,6 +153,7 @@ static ssize_t kexec_crash_size_store(struct kobject *kobj,
|
||||
}
|
||||
KERNEL_ATTR_RW(kexec_crash_size);
|
||||
|
||||
#endif /* CONFIG_CRASH_DUMP*/
|
||||
#endif /* CONFIG_KEXEC_CORE */
|
||||
|
||||
#ifdef CONFIG_VMCORE_INFO
|
||||
@ -262,9 +264,11 @@ static struct attribute * kernel_attrs[] = {
|
||||
#endif
|
||||
#ifdef CONFIG_KEXEC_CORE
|
||||
&kexec_loaded_attr.attr,
|
||||
#ifdef CONFIG_CRASH_DUMP
|
||||
&kexec_crash_loaded_attr.attr,
|
||||
&kexec_crash_size_attr.attr,
|
||||
#endif
|
||||
#endif
|
||||
#ifdef CONFIG_VMCORE_INFO
|
||||
&vmcoreinfo_attr.attr,
|
||||
#ifdef CONFIG_CRASH_HOTPLUG
|
||||
|
||||
Loading…
Reference in New Issue
Block a user