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-rw-r--r--arch/x86_64/kernel/crash.c70
1 files changed, 70 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/crash.c b/arch/x86_64/kernel/crash.c
index abc601f36b6e..4e6c3b729e39 100644
--- a/arch/x86_64/kernel/crash.c
+++ b/arch/x86_64/kernel/crash.c
@@ -11,9 +11,12 @@
11#include <linux/types.h> 11#include <linux/types.h>
12#include <linux/kernel.h> 12#include <linux/kernel.h>
13#include <linux/smp.h> 13#include <linux/smp.h>
14#include <linux/irq.h>
14#include <linux/reboot.h> 15#include <linux/reboot.h>
15#include <linux/kexec.h> 16#include <linux/kexec.h>
16#include <linux/delay.h> 17#include <linux/delay.h>
18#include <linux/elf.h>
19#include <linux/elfcore.h>
17 20
18#include <asm/processor.h> 21#include <asm/processor.h>
19#include <asm/hardirq.h> 22#include <asm/hardirq.h>
@@ -24,6 +27,71 @@
24/* This keeps a track of which one is crashing cpu. */ 27/* This keeps a track of which one is crashing cpu. */
25static int crashing_cpu; 28static int crashing_cpu;
26 29
30static u32 *append_elf_note(u32 *buf, char *name, unsigned type,
31 void *data, size_t data_len)
32{
33 struct elf_note note;
34
35 note.n_namesz = strlen(name) + 1;
36 note.n_descsz = data_len;
37 note.n_type = type;
38 memcpy(buf, &note, sizeof(note));
39 buf += (sizeof(note) +3)/4;
40 memcpy(buf, name, note.n_namesz);
41 buf += (note.n_namesz + 3)/4;
42 memcpy(buf, data, note.n_descsz);
43 buf += (note.n_descsz + 3)/4;
44
45 return buf;
46}
47
48static void final_note(u32 *buf)
49{
50 struct elf_note note;
51
52 note.n_namesz = 0;
53 note.n_descsz = 0;
54 note.n_type = 0;
55 memcpy(buf, &note, sizeof(note));
56}
57
58static void crash_save_this_cpu(struct pt_regs *regs, int cpu)
59{
60 struct elf_prstatus prstatus;
61 u32 *buf;
62
63 if ((cpu < 0) || (cpu >= NR_CPUS))
64 return;
65
66 /* Using ELF notes here is opportunistic.
67 * I need a well defined structure format
68 * for the data I pass, and I need tags
69 * on the data to indicate what information I have
70 * squirrelled away. ELF notes happen to provide
71 * all of that that no need to invent something new.
72 */
73
74 buf = (u32*)per_cpu_ptr(crash_notes, cpu);
75
76 if (!buf)
77 return;
78
79 memset(&prstatus, 0, sizeof(prstatus));
80 prstatus.pr_pid = current->pid;
81 elf_core_copy_regs(&prstatus.pr_reg, regs);
82 buf = append_elf_note(buf, "CORE", NT_PRSTATUS, &prstatus,
83 sizeof(prstatus));
84 final_note(buf);
85}
86
87static void crash_save_self(struct pt_regs *regs)
88{
89 int cpu;
90
91 cpu = smp_processor_id();
92 crash_save_this_cpu(regs, cpu);
93}
94
27#ifdef CONFIG_SMP 95#ifdef CONFIG_SMP
28static atomic_t waiting_for_crash_ipi; 96static atomic_t waiting_for_crash_ipi;
29 97
@@ -38,6 +106,7 @@ static int crash_nmi_callback(struct pt_regs *regs, int cpu)
38 return 1; 106 return 1;
39 local_irq_disable(); 107 local_irq_disable();
40 108
109 crash_save_this_cpu(regs, cpu);
41 disable_local_APIC(); 110 disable_local_APIC();
42 atomic_dec(&waiting_for_crash_ipi); 111 atomic_dec(&waiting_for_crash_ipi);
43 /* Assume hlt works */ 112 /* Assume hlt works */
@@ -113,4 +182,5 @@ void machine_crash_shutdown(struct pt_regs *regs)
113 disable_IO_APIC(); 182 disable_IO_APIC();
114#endif 183#endif
115 184
185 crash_save_self(regs);
116} 186}