各位有没有见过这种错误，或者有没有其他方法可以查错的dmesg显示
bug unable to handle kernel paging request at 00007ffda441a050

int ret,fd;

char toSend[LENGTH]={0};

fd=open("/dev/charMsgDriver",O_RDWR);

scanf("%[^\n]%*c",toSend);

ret=write(fd,toSend,strlen(toSend));//fd,toSend,strlen(toSend)都是有值，到这句的时候就不会执行，直接退出，后面不会执行了也查不了错。

charMsgDriver应该是一个内核的字符驱动模块在root下执行该程序，执行到write时显示“已杀死”

[此贴子已经被作者于2018-6-27 17:20编辑过]

strace ./程序 或者生成core文件gdb调试一下 你这样能看得到什么

LENGTH 多大
你读取了多少个字符?

length大小是1024，测试的是输四个字符abcd

execve("./test", ["./test"], [/* 83 vars */]) = 0
brk(0)                                  = 0x66f000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fd0a490e000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/home/qianyang/catkin_ws/devel/lib/tls/x86_64/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
stat("/home/qianyang/catkin_ws/devel/lib/tls/x86_64", 0x7ffd1bd47ce0) = -1 ENOENT (No such file or directory)
open("/home/qianyang/catkin_ws/devel/lib/tls/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
stat("/home/qianyang/catkin_ws/devel/lib/tls", 0x7ffd1bd47ce0) = -1 ENOENT (No such file or directory)
open("/home/qianyang/catkin_ws/devel/lib/x86_64/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
stat("/home/qianyang/catkin_ws/devel/lib/x86_64", 0x7ffd1bd47ce0) = -1 ENOENT (No such file or directory)
open("/home/qianyang/catkin_ws/devel/lib/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
stat("/home/qianyang/catkin_ws/devel/lib", {st_mode=S_IFDIR|0775, st_size=4096, ...}) = 0
open("/opt/ros/indigo/lib/tls/x86_64/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
stat("/opt/ros/indigo/lib/tls/x86_64", 0x7ffd1bd47ce0) = -1 ENOENT (No such file or directory)
open("/opt/ros/indigo/lib/tls/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
stat("/opt/ros/indigo/lib/tls", 0x7ffd1bd47ce0) = -1 ENOENT (No such file or directory)
open("/opt/ros/indigo/lib/x86_64/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
stat("/opt/ros/indigo/lib/x86_64", 0x7ffd1bd47ce0) = -1 ENOENT (No such file or directory)
open("/opt/ros/indigo/lib/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
stat("/opt/ros/indigo/lib", {st_mode=S_IFDIR|0755, st_size=20480, ...}) = 0
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=164111, ...}) = 0
mmap(NULL, 164111, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fd0a48e5000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P \2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1853216, ...}) = 0
mmap(NULL, 3961536, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fd0a4326000
mprotect(0x7fd0a44e4000, 2093056, PROT_NONE) = 0
mmap(0x7fd0a46e3000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1bd000) = 0x7fd0a46e3000
mmap(0x7fd0a46e9000, 17088, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fd0a46e9000
close(3)                                = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fd0a48e4000
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fd0a48e2000
arch_prctl(ARCH_SET_FS, 0x7fd0a48e2740) = 0
mprotect(0x7fd0a46e3000, 16384, PROT_READ) = 0
mprotect(0x600000, 4096, PROT_READ)     = 0
mprotect(0x7fd0a4910000, 4096, PROT_READ) = 0
munmap(0x7fd0a48e5000, 164111)          = 0
fstat(1, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 1), ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fd0a490d000
write(1, "\n", 1
)                       = 1
open("/dev/charMsgDriver", O_RDWR)      = -1 ENOENT (No such file or directory)
dup(2)                                  = 3
fcntl(3, F_GETFL)                       = 0x8002 (flags O_RDWR|O_LARGEFILE)
brk(0)                                  = 0x66f000
brk(0x690000)                           = 0x690000
fstat(3, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 1), ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fd0a490c000
lseek(3, 0, SEEK_CUR)                   = -1 ESPIPE (Illegal seek)
write(3, "failed to open charMsgDriver dev"..., 37failed to open charMsgDriver device.
) = 37
write(3, ": No such file or directory\n", 28: No such file or directory
) = 28
close(3)                                = 0
munmap(0x7fd0a490c000, 4096)            = 0
exit_group(2)                           = ?
+++ exited with 2 +++

这不是都有了么

[此贴子已经被作者于2018-6-28 11:16编辑过]

是的，很奇怪，我看过那个目录下那个文件是在的

[此贴子已经被作者于2018-6-28 12:47编辑过]

不好意思，上面那个strace执行的时候好像因为重启，把那个文件给删了，所以找不到，我把文件又加进去再strace一下结果是

qianyang@qianyang-Lenovo-XiaoXin-700-15ISK:~/embed/4/userApp$ sudo strace ./test

execve("./test", ["./test"], [/* 18 vars */]) = 0
brk(0)                                  = 0x12ed000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f5087bd3000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=164111, ...}) = 0
mmap(NULL, 164111, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f5087baa000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P \2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1853216, ...}) = 0
mmap(NULL, 3961536, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f50875eb000
mprotect(0x7f50877a9000, 2093056, PROT_NONE) = 0
mmap(0x7f50879a8000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1bd000) = 0x7f50879a8000
mmap(0x7f50879ae000, 17088, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f50879ae000
close(3)                                = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f5087ba9000
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f5087ba7000
arch_prctl(ARCH_SET_FS, 0x7f5087ba7740) = 0
mprotect(0x7f50879a8000, 16384, PROT_READ) = 0
mprotect(0x600000, 4096, PROT_READ)     = 0
mprotect(0x7f5087bd5000, 4096, PROT_READ) = 0
munmap(0x7f5087baa000, 164111)          = 0
fstat(1, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 5), ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f5087bd2000
write(1, "\n", 1
)                       = 1
open("/dev/charMsgDriver", O_RDWR)      = 3
write(1, "type something to the kernel mod"..., 37type something to the kernel module:
) = 37
fstat(0, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 5), ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f5087bd1000
read(0, 0x7f5087bd1000, 1024)           = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
--- SIGWINCH {si_signo=SIGWINCH, si_code=SI_KERNEL} ---
read(0, 0x7f5087bd1000, 1024)           = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
--- SIGWINCH {si_signo=SIGWINCH, si_code=SI_KERNEL} ---
read(0,       

最后 read(0), 是在等标准输入吧

scanf 读取输入报错了