aboutsummaryrefslogtreecommitdiffstats
path: root/include/asm-x86_64/kexec.h
diff options
context:
space:
mode:
authorVivek Goyal <vgoyal@in.ibm.com>2006-01-09 23:51:49 -0500
committerLinus Torvalds <torvalds@g5.osdl.org>2006-01-10 11:01:28 -0500
commitec9ce0dbaa734bc95ec73cf5c13f202f1adb219d (patch)
tree26d799567fe0325ae918e4f0bffa5080a03faeff /include/asm-x86_64/kexec.h
parentcffe632a25b017dac4b6f060cad31940c6c167b4 (diff)
[PATCH] kdump: x86_64 save cpu registers upon crash
- Saving the cpu registers of all cpus before booting in to the crash kernel. - crash_setup_regs will save the registers of the cpu on which panic has occured. One of the concerns ppc64 folks raised is that after capturing the register states, one should not pop the current call frame and push new one. Hence it has been inlined. More call frames later get pushed on to stack (machine_crash_shutdown() and machine_kexec()), but one will not want to backtrace those. - Not very sure about the CFI annotations. With this patch I am getting decent backtrace with gdb. Assuming, compiler has generated enough debugging information for crash_kexec(). Coding crash_setup_regs() in pure assembly makes it tricky because then it can not be inlined and we don't want to return back after capturing register states we don't want to pop this call frame. - Saving the non-panicing cpus registers will be done in the NMI handler while shooting down them in machine_crash_shutdown. - Introducing CRASH_DUMP option in Kconfig for x86_64. Signed-off-by: Murali M Chakravarthy <muralim@in.ibm.com> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Cc: Andi Kleen <ak@muc.de> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/asm-x86_64/kexec.h')
-rw-r--r--include/asm-x86_64/kexec.h36
1 files changed, 36 insertions, 0 deletions
diff --git a/include/asm-x86_64/kexec.h b/include/asm-x86_64/kexec.h
index cea78543a574..ae28cd44bcd3 100644
--- a/include/asm-x86_64/kexec.h
+++ b/include/asm-x86_64/kexec.h
@@ -3,6 +3,7 @@
3 3
4#include <asm/page.h> 4#include <asm/page.h>
5#include <asm/proto.h> 5#include <asm/proto.h>
6#include <asm/ptrace.h>
6 7
7/* 8/*
8 * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return. 9 * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
@@ -27,4 +28,39 @@
27 28
28#define MAX_NOTE_BYTES 1024 29#define MAX_NOTE_BYTES 1024
29 30
31/*
32 * Saving the registers of the cpu on which panic occured in
33 * crash_kexec to save a valid sp. The registers of other cpus
34 * will be saved in machine_crash_shutdown while shooting down them.
35 */
36
37static inline void crash_setup_regs(struct pt_regs *newregs,
38 struct pt_regs *oldregs)
39{
40 if (oldregs)
41 memcpy(newregs, oldregs, sizeof(*newregs));
42 else {
43 __asm__ __volatile__("movq %%rbx,%0" : "=m"(newregs->rbx));
44 __asm__ __volatile__("movq %%rcx,%0" : "=m"(newregs->rcx));
45 __asm__ __volatile__("movq %%rdx,%0" : "=m"(newregs->rdx));
46 __asm__ __volatile__("movq %%rsi,%0" : "=m"(newregs->rsi));
47 __asm__ __volatile__("movq %%rdi,%0" : "=m"(newregs->rdi));
48 __asm__ __volatile__("movq %%rbp,%0" : "=m"(newregs->rbp));
49 __asm__ __volatile__("movq %%rax,%0" : "=m"(newregs->rax));
50 __asm__ __volatile__("movq %%rsp,%0" : "=m"(newregs->rsp));
51 __asm__ __volatile__("movq %%r8,%0" : "=m"(newregs->r8));
52 __asm__ __volatile__("movq %%r9,%0" : "=m"(newregs->r9));
53 __asm__ __volatile__("movq %%r10,%0" : "=m"(newregs->r10));
54 __asm__ __volatile__("movq %%r11,%0" : "=m"(newregs->r11));
55 __asm__ __volatile__("movq %%r12,%0" : "=m"(newregs->r12));
56 __asm__ __volatile__("movq %%r13,%0" : "=m"(newregs->r13));
57 __asm__ __volatile__("movq %%r14,%0" : "=m"(newregs->r14));
58 __asm__ __volatile__("movq %%r15,%0" : "=m"(newregs->r15));
59 __asm__ __volatile__("movl %%ss, %%eax;" :"=a"(newregs->ss));
60 __asm__ __volatile__("movl %%cs, %%eax;" :"=a"(newregs->cs));
61 __asm__ __volatile__("pushfq; popq %0" :"=m"(newregs->eflags));
62
63 newregs->rip = (unsigned long)current_text_addr();
64 }
65}
30#endif /* _X86_64_KEXEC_H */ 66#endif /* _X86_64_KEXEC_H */