1.\" SPDX-License-Identifier: BSD-2-Clause 2.\" 3.\" Copyright (c) 2022, Jake Freeland <jfree@freebsd.org> 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25 26.Dd August 10, 2022 27.Dt LINDEBUGFS 5 28.Os 29.Sh NAME 30.Nm lindebugfs 31.Nd Linux file system for debugging 32.Sh SYNOPSIS 33.Bd -literal 34lindebugfs /sys/kernel/debug lindebugfs rw 0 0 35.Ed 36.Sh DESCRIPTION 37The debug file system, or debugfs, makes process debugging easier by 38providing a simple API for data transfer between the kernel and user 39space. 40Debugfs is not a general-purpose file system and should not be used as 41a storage medium. 42Instead, developers can implement the debugfs interface in their code 43to generate debug information about their program at runtime. 44FreeBSD's 45.Nm 46uses the 47.Xr pseudofs 9 48file system construction kit to model itself after Linux's debugfs. 49The 50.Nm 51API is intended for use with programs that take advantage of FreeBSD's 52LinuxKPI compatibility layer. 53.Pp 54When mounted, 55.Nm 56will populate with pseudo files from any running process that calls 57.Nm debugfs_create_file() . 58Since 59.Nm 60is a pseudo file system, file contents will be generated dynamically 61based on program provided file operations. 62The current 63.Nm 64implementation formally supports seq_file and simple_attr_file virtual 65file formats. 66.Sh EXAMPLES 67Load the 68.Nm 69kernel module: 70.Pp 71.Dl "kldload lindebugfs" 72.Pp 73Mount the 74.Nm 75file system on 76.Pa /sys/kernel/debug : 77.Pp 78.Dl "mount -t lindebugfs lindebugfs /sys/kernel/debug" 79.Sh SEE ALSO 80.Xr linprocfs 5 , 81.Xr linsysfs 5 , 82.Xr pseudofs 9 , 83.Xr linux 4 , 84.Xr mount 1 85.Sh HISTORY 86The 87.Nm 88file system first appeared in 89.Fx 12.1 . 90.Sh AUTHORS 91.An -nosplit 92The initial implementation for 93.Nm 94was created by Matthew Macy. 95This manual page was written by Jake Freeland. 96