xref: /netbsd-src/share/man/man9/crashme.9 (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
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29.Dd January 7, 2019
30.Dt CRASHME 9
31.Os
32.Sh NAME
33.Nm crashme ,
34.Nm crashme_add ,
35.Nm crashme_remove
36.Nd in-kernel testing of crash handling
37.Sh SYNOPSIS
38.In sys/crashme.h
39.Ft int
40.Fn crashme_add "crashme_node *cn"
41.Ft int
42.Fn crashme_remove "crashme_node *cn"
43.Sh DESCRIPTION
44The
45.Nm
46functions provide access to dynamically add and remove crashme nodes.
47These nodes are simply named callbacks that are expected to cause the
48system to crash.
49.Pp
50The crashme functionality is only available in kernels with the
51.Xr options 4
52.Dv DEBUG
53option set.
54.Pp
55Each crashme node is maintained in a
56.Vt crashme_node
57structure which has the following public members:
58.Bd -literal
59typedef int (*crashme_fn)(int);
60
61typedef struct crashme_node {
62	const char	*cn_name;
63	const char	*cn_longname;
64	crashme_fn	 cn_fn;
65} crashme_node;
66.Ed
67.Pp
68The
69caller must fill in the
70.Fa cn_name ,
71.Fa cn_longname ,
72and
73.Fa cn_fn
74members.
75.Pp
76The
77.Ar flags
78parameter is passed from sysctl.
79The return value is 0 upon success or non zero for failure.
80.Sh SYSCTL SUPPORT
81The following
82.Xr sysctl 8
83variables are provided by the
84.Nm
85subsystem:
86.Bl -tag -width "123456" -offset indent
87.It Ic debug.crashme_enable
88Must be set to 1 for any
89.Nm
90node to be executed.
91.It Ic debug.crashme.panic
92Basic panic node.
93.It Ic debug.crashme.null_deref
94Dereference
95.Dv NULL
96node.
97.El
98.Sh SEE ALSO
99.Xr options 4 ,
100.Xr panic 9
101.Sh HISTORY
102The
103.Nm
104driver appeared in
105.Nx 9.0 .
106.Sh AUTHORS
107.An Matthew R. Green
108