0000000000056ee9
<console_print>:
56ee9: 55
push %rbp
56eea: 48 89 e5
mov %rsp,%rbp
56eed: 41 57
push %r15
56eef: 41 56
push %r14
56ef1: 41 55
push %r13
56ef3: 41 54
push %r12
56ef5: 53
push %rbx
56ef6: 48 83 ec
18
sub $0x18,%rsp
56efa: 49 89 fe
mov %rdi,%r14
56efd: 41 89 d4
mov %edx,%r12d
56f00: 48 89 65
c0
mov %rsp,-0x40(%rbp)
56f04: 8d 42 01
lea
0x1(%rdx),%eax
56f07: 48 98
cltq
56f09: 48 83 c0
0f
add $0xf,%rax
56f0d: 48 83 e0
f0
and $0xfffffffffffffff0,%rax
56f11: 48 29 c4
sub %rax,%rsp
56f14: 48 89 e3
mov %rsp,%rbx
56f17: 83 3d 00
00 00 00
00 cmpl $0x0,0x0(%rip) # 56f1e
<console_print+0x35>
56f1e: 74 09
je 56f29
<console_print+0x40>
56f20: 4c 8b 3d
00 00 00
00 mov 0x0(%rip),%r15 #
56f27 <console_print+0x3e>
56f27: eb 07
jmp 56f30
<console_print+0x47>
56f29: 4c 8b 3d
00 00 00
00 mov 0x0(%rip),%r15 #
56f30 <console_print+0x47>
56f30: 4d 85 f6
test %r14,%r14
56f33: 74 19
je 56f4e
<console_print+0x65>
56f35: 41 80 7e
30 00
cmpb $0x0,0x30(%r14)
56f3a: 74 12
je 56f4e
<console_print+0x65>
56f3c: 44 89 e2
mov %r12d,%edx
56f3f: 4c 89 f7
mov %r14,%rdi
56f42: 41 ff d7
callq *%r15
56f45: 48 8b 65
c0
mov -0x40(%rbp),%rsp
56f49: e9 84 00
00
00 jmpq 56fd2
<console_print+0xe9>
56f4e: 4d 63 ec
movslq %r12d,%r13
56f51: 4c 89 ea
mov %r13,%rdx
56f54: 48 89 df
mov %rbx,%rdi
56f57: e8 00 00
00
00 callq 56f5c
<console_print+0x73>
56f5c: 4a 8d 44
2b
ff lea -0x1(%rbx,%r13,1),%rax
56f61: 48 39 c3
cmp %rax,%rbx
56f64: 73 4b
jae 56fb1
<console_print+0xc8>
56f66: 48 89 de
mov %rbx,%rsi
56f69: 80 3b 0a
cmpb $0xa,(%rbx)
56f6c: 75 30
jne 56f9e
<console_print+0xb5>
56f6e: c6 03 0d
movb $0xd,(%rbx)
56f71: 0f b6 43
01
movzbl 0x1(%rbx),%eax
56f75: 88 45 cf
mov
%al,-0x31(%rbp)
56f78: c6 43 01
0a
movb $0xa,0x1(%rbx)
56f7c: 49 89 dd
mov %rbx,%r13
56f7f: 49 29 f5
sub %rsi,%r13
56f82: 41 8d 55
02
lea 0x2(%r13),%edx
56f86: 4c 89 f7
mov %r14,%rdi
56f89: 41 ff d7
callq *%r15
56f8c: 0f b6 45
cf
movzbl -0x31(%rbp),%eax
56f90: 88 43 01
mov %al,0x1(%rbx)
56f93: 48 8d 73
01
lea 0x1(%rbx),%rsi
56f97: 41 83 c5
01
add $0x1,%r13d
56f9b: 45 29 ec
sub %r13d,%r12d
56f9e: 48 83 c3
01
add $0x1,%rbx
56fa2: 4d 63 ec
movslq %r12d,%r13
56fa5: 4a 8d 44
2e
ff lea -0x1(%rsi,%r13,1),%rax
56faa: 48 39 d8
cmp %rbx,%rax
56fad: 77 ba
ja 56f69
<console_print+0x80>
56faf: eb 03
jmp 56fb4
<console_print+0xcb>
56fb1: 48 89 de
mov %rbx,%rsi
56fb4: 80 38 0a
cmpb $0xa,(%rax)
56fb7: 75 0c
jne 56fc5 <console_print+0xdc>
56fb9: c6 00 0d
movb $0xd,(%rax)
56fbc: 42 c6 04
2e
0a movb $0xa,(%rsi,%r13,1)
56fc1: 41 83 c4
01
add $0x1,%r12d
56fc5: 44 89 e2
mov %r12d,%edx
56fc8: 4c 89 f7
mov %r14,%rdi
56fcb:
41 ff d7
callq *%r15
56fce: 48 8b 65
c0
mov -0x40(%rbp),%rsp
56fd2: 48 8d 65
d8
lea -0x28(%rbp),%rsp
56fd6: 5b
pop
%rbx
56fd7: 41 5c
pop %r12
56fd9: 41 5d
pop %r13
56fdb: 41 5e
pop %r14
56fdd: 41 5f
pop %r15
56fdf: 5d
pop
%rbp
56fe0: c3
retq
I
added the options –fno-pic to TARGET_CFLAGS and
TARGET_CPPFLAGS and –no-pie to TARGET_LDFLAGS and recompile
the kernel. Now,
the kernel carshed at instruction 0x673bb in the
run_idle_thread function:
00000000000673ac
<run_idle_thread>:
673ac: 55
push %rbp
673ad: 48 89 e5
mov %rsp,%rbp
673b0: 48 8b 05
00 00 00
00 mov 0x0(%rip),%rax #
673b7 <run_idle_thread+0xb>
673b7: 48 8b 60
10
mov 0x10(%rax),%rsp
673bb: ff 70 18
pushq 0x18(%rax)
673be: c3
retq
673bf: 5d
pop
%rbp
673c0: c3
retq
Finally,
just to try I commented out the run_idle_thread
function and the kernel crashed at the very beginning at
0x63. The kern dump in
this case points to the stack:
5e: e8 00 00 00 00 callq
63 <stack_start>
