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diff --git a/static/openbsd/man4/options.4 b/static/openbsd/man4/options.4 new file mode 100644 index 00000000..635532df --- /dev/null +++ b/static/openbsd/man4/options.4 @@ -0,0 +1,551 @@ +.\" $OpenBSD: options.4,v 1.273 2025/06/01 00:32:54 rsadowski Exp $ +.\" $NetBSD: options.4,v 1.21 1997/06/25 03:13:00 thorpej Exp $ +.\" +.\" Copyright (c) 1998 Theo de Raadt +.\" Copyright (c) 1998 Todd Miller +.\" Copyright (c) 1998 Gene Skonicki +.\" Copyright (c) 1996 +.\" Perry E. Metzger. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgment: +.\" This product includes software developed for the NetBSD Project +.\" by Perry E. Metzger. +.\" 4. The name of the author may not be used to endorse or promote products +.\" derived from this software without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR +.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES +.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. +.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, +.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT +.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF +.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +.\" +.\" +.Dd $Mdocdate: June 1 2025 $ +.Dt OPTIONS 4 +.Os +.Sh NAME +.Nm options +.Nd kernel configuration options +.Sh SYNOPSIS +.Cd option ... +.Sh DESCRIPTION +This manual page describes a number of miscellaneous kernel +configuration options that may be specified in a kernel config file. +See +.Xr config 8 +for information on how to configure and build kernels. +.Em Note : +options are passed to the compile process as +.Fl D +flags to the C compiler. +.Sh DEBUGGING OPTIONS +.Bl -ohang +.It Cd makeoptions DEBUG="" +Do not build the debug kernel +.Pa bsd.gdb . +Normally, +.Pa bsd.gdb +is built +(in addition to the regular +.Pa bsd +kernel) +and is used for debugging kernels and their crash dumps with +.Xr gdb 1 . +A crash dump can be debugged by starting gdb with +.Pa bsd.gdb +as an argument (no core file) and then using the gdb command +.Dq target kvm COREFILE . +.It Cd makeoptions PROF="-pg" +The +.Fl pg +flag causes the kernel to be compiled with support for profiling. +The +.Cm option GPROF +is required for the kernel compile to succeed. +.It Cd option ACCOUNTING +Adds support for the +.Xr acct 2 +system call. +.It Cd option DDB +Compiles in a kernel debugger for diagnosing kernel problems. +See +.Xr ddb 4 . +.It Cd option DDB_SAFE_CONSOLE +Allows a break into the kernel debugger during boot. +Useful when debugging problems that can cause +.Xr init 8 +to fail. +.It Cd option DEBUG +Turns on miscellaneous kernel debugging. +Since options are turned into preprocessor defines (see above), +.Cm option DEBUG +is equivalent to doing a +.Em #define DEBUG +throughout the kernel. +Much of the kernel has +.Em #ifdef DEBUG +conditional debugging code. +Note that many parts of the kernel (typically device drivers) include their own +.Em #ifdef XXX_DEBUG +conditionals instead. +.It Cd option DIAGNOSTIC +Adds code to the kernel that does internal consistency checks. +This code will cause the kernel to panic if corruption of internal data +structures is detected. +.It Cd option GPROF +Adds code to the kernel for kernel profiling with +.Xr kgmon 8 . +.It Cd option KTRACE +Adds hooks for the system call tracing facility, which allows users to +watch the system call invocation behavior of processes. +See +.Xr ktrace 1 . +.It Cd option KUBSAN +Detect undefined behavior in the kernel. +See +.Xr kubsan 4 . +.It Cd option NO_PROPOLICE +Do not compile the kernel with the ProPolice stack protection. +See +.Xr gcc-local 1 +for more information about ProPolice. +.It Cd option PTRACE +Adds hooks for the process tracing facility, allowing a process to +control and observe another process. +See +.Xr ptrace 2 . +.It Cd option SMALL_KERNEL +Removes some features and some optimizations from the kernel to reduce the +size of the resulting kernel binary. +This option is used on some installation media and should not be used +for general purpose kernels. +.It Cd option VFSLCKDEBUG +Turns on debugging for the Virtual File System interface. +See +.Xr vfs 9 . +.It Cd option WITNESS +Compiles in a lock checker for detecting lock order violations in the kernel. +See +.Xr witness 4 . +.It Cd option WITNESS_COUNT= Ns Ar integer +Maximum number of lock types that are tracked by +.Xr witness 4 . +It defaults to 1536. +.It Cd option WITNESS_LOCKTRACE +Enable +.Xr witness 4 +lock stack trace saving at boot. +The feature is disabled by default and has to be enabled by setting the +.Va kern.witness.locktrace +.Xr sysctl 8 +variable. +.It Cd option WITNESS_WATCH +Enable +.Xr witness 4 +at boot. +By default, the subsystem is disabled and has to be enabled at runtime +by raising the +.Va kern.witness.watch +.Xr sysctl 8 +variable. +.El +.Sh FILE SYSTEMS +.Bl -ohang +.It Cd option CD9660 +Includes code for the ISO 9660 + Rock Ridge file system, which is the +standard file system used on many CD-ROMs. +It also supports Joliet extensions. +See +.Xr mount_cd9660 8 . +.It Cd option FFS +Includes code implementing the Berkeley Fast File System +.Em ( FFS ) . +Most machines need this if they are not running diskless. +.It Cd option FFS2 +Includes code implementing the enhanced Fast File System +.Em ( FFS2 ) . +.It Cd option MFS +Include the memory file system +.Em ( MFS ) . +This file system stores files in swappable memory, and produces +notable performance improvements when it is used as the file store +for +.Pa /tmp +or similar mount points. +See +.Xr mount_mfs 8 . +.It Cd option MSDOSFS +Includes support for the MS-DOS FAT file system. +The kernel also implements the Windows 95 +extensions which permit the use of longer, mixed-case file names. +See +.Xr mount_msdos 8 +and +.Xr fsck_msdos 8 . +.It Cd option NFSCLIENT +Include the client side of the +.Em NFS +(Network File System) remote file sharing protocol. +Although the bulk of the code implementing +.Em NFS +is kernel based, several user level daemons are needed for it to work. +See +.Xr mount_nfs 8 +for details on NFS. +.It Cd option NTFS +Includes support for reading NTFS file systems. +See +.Xr mount_ntfs 8 . +.It Cd option UDF +Includes code for the UDF file systems typically found on DVD discs. +See +.Xr mount_udf 8 . +.It Cd option TMPFS +Includes code for the TMPFS efficient memory file system. +See +.Xr mount_tmpfs 8 . +.El +.Sh FILE SYSTEM OPTIONS +.Bl -ohang +.It Cd option BUFCACHEPERCENT= Ns Ar integer +The maximum percentage of DMA-reachable physical memory the buffer cache may use. +.It Cd option EXT2FS_SYSTEM_FLAGS +This option changes the behavior of the APPEND and IMMUTABLE flags +for a file on an +.Em EXT2FS +filesystem. +Without this option, the superuser or owner of the file can set and clear them. +With this option, only the superuser can set them, and they can't be cleared +if the securelevel is greater than 0. +See also +.Xr chflags 1 . +.It Cd option FIFO +Adds support for +.At V +style FIFOs (i.e., +.Dq named pipes ) . +This option is recommended in almost all cases as many programs use these. +.It Cd option NFSSERVER +Include the server side of the +.Em NFS +(Network File System) remote file sharing protocol. +Although the bulk of the code implementing +.Em NFS +is kernel based, several user level daemons are needed for it to +work. +See +.Xr mountd 8 +and +.Xr nfsd 8 . +.It Cd option QUOTA +Enables kernel support for file system quotas. +See +.Xr quotaon 8 , +.Xr edquota 8 , +.Xr repquota 8 , +and +.Xr quota 1 . +Note that quotas only work on +.Dq ffs +file systems, although +.Xr rpc.rquotad 8 +permits them to be accessed over +.Em NFS . +.It Cd option UFS_DIRHASH +This option enables using an in memory hash table to speed lookups +in large directories. +.El +.Sh MISCELLANEOUS OPTIONS +.Bl -ohang +.It Cd option APERTURE +Provide in-kernel support for controlling VGA framebuffer mapping +and PCI configuration registers by user-processes +(such as an X Window System server). +See +.Xr xf86 4 . +This option is supported on the +.Va alpha , +.Va amd64 , +.Va i386 , +.Va macppc , +and +.Va sparc64 +architectures. +.It Cd option BOOT_CONFIG +Adds support for the +.Fl c +boot option (User Kernel Config). +Allows modification of kernel settings (e.g., device parameters) before +booting the system. +See +.Xr boot_config 8 . +.It Cd option CRYPTO +Enables support for the kernel cryptographic framework. +See +.Xr crypto 9 . +While not IP specific, this option is usually used in conjunction with option +.Em IPSEC . +.It Cd option EISAVERBOSE +Makes the boot process more verbose for EISA peripherals. +See +.Xr eisa 4 . +.It Cd option KMEMSTATS +The kernel memory allocator, +.Xr malloc 9 , +will keep statistics on its performance if this option is enabled. +.It Cd option MULTIPROCESSOR +On those architectures that have it, this enables multiprocessor support. +.It Cd option PCIVERBOSE +Makes the boot process more verbose for PCI peripherals +(vendor names and other information is printed, etc.). +See +.Xr pci 4 . +.It Cd option PCMCIAVERBOSE +Makes the boot process more verbose for PCMCIA peripherals. +See +.Xr pcmcia 4 . +.It Cd option USER_PCICONF +Enables the user level access to the PCI bus configuration space +through ioctls on the +.Pa /dev/pci +device. +It's used by +.Xr Xorg 1 +and +.Xr pcidump 8 . +See +.Xr pci 4 . +.It Cd option UVM_SWAP_ENCRYPT +Enables kernel support for encrypting pages that are written out to +swap storage. +Swap encryption prevents sensitive data from remaining +on the disk even after the operating system has been shut down. +This option should be turned on if cryptographic filesystems are used. +The sysctl variable +.Em vm.swapencrypt.enable +controls its behaviour. +See +.Xr sysctl 8 +and +.Xr sysctl 2 . +.El +.Sh NETWORKING OPTIONS +.Bl -ohang +.It Cd option ENCDEBUG +This option permits the conditional logging of IPsec debugging information, +and requires the +.Em IPSEC +option. +Debug logging can be turned on/off through the use of the +.Em net.inet.ip.encdebug +sysctl variable. +If +.Em net.inet.ip.encdebug +is 1, debug logging is on. +See +.Xr sysctl 8 +and +.Xr sysctl 2 . +.It Cd option INET6 +Includes support for the IPv6 protocol stack. +See +.Xr inet6 4 . +.Em INET6 +enables multicast routing code as well. +.It Cd option IPSEC +This option enables IP security protocol support. +See +.Xr ipsec 4 +for more details. +.It Cd option MROUTING +Includes support for IP multicast routers. +Multicast routing is controlled by the +.Xr mrouted 8 +daemon. +.It Cd option PIPEX +Includes pipex in-kernel acceleration for PPPoE, L2TP or PPTP. +See +.Xr pipex 4 . +.It Cd option PPP_BSDCOMP +Enables BSD compressor for PPP connections. +.It Cd option PPP_DEFLATE +For use in conjunction with PPP_BSDCOMP; provides an interface to zlib for PPP +for deflate compression/decompression. +.It Cd option PPPOE_TERM_UNKNOWN_SESSIONS +Send PADT to terminate open sessions before connecting. +See +.Xr pppoe 4 . +.It Cd option SOCKET_SPLICE +Enables zero-copy socket splicing in the kernel. +See +.Dv SO_SPLICE +in +.Xr setsockopt 2 +and +.Xr sosplice 9 . +.It Cd option TCP_ECN +Turns on Explicit Congestion Notification (RFC 3168). +.Em ECN +allows intermediate routers to use the Congestion Experienced +codepoint in the IP header as an indication of congestion, and allows +TCP to adjust the transmission rate using this signal. +Both communication endpoints negotiate enabling +.Em ECN +functionality at the TCP connection establishment. +.It Cd option TCP_SIGNATURE +Turns on support for the TCP MD5 Signature option (RFC 2385). +This is used by +Internet backbone routers to provide per-packet authentication for the TCP +packets used to communicate BGP routing information. +You will also need a +routing daemon that supports this option in order to actually use it. +.El +.Sh OPERATION RELATED OPTIONS +.Bl -ohang -compact +.It Cd option BUFPAGES= Ns Ar value +This option sets the number of pages available for the buffer cache. +The default value is machine dependent, often calculated as +between 5% and 10% of total available RAM. +.Pp +.It Cd option NKMEMPAGES= Ns Ar value +Size of kernel malloc area in PAGE_SIZE-sized logical pages. +This area is covered by the kernel submap +.Em kmem_map . +The kernel attempts to auto-size this map based on the amount of +physical memory in the system. +Platform-specific code may place bounds on this computed size, +which may be viewed with the +.Xr sysctl 8 +variable +.Em vm.nkmempages . +.El +.Sh SCSI SUBSYSTEM OPTIONS +See +.Xr scsi 4 . +.Bl -ohang +.It Cd option SCSI_DELAY= Ns Ar value +Delay for +.Ar value +seconds before starting to probe the first SCSI bus. +This can be used if a SCSI device needs extra time to get ready. +.It Cd option SCSIDEBUG +Enable printing of SCSI subsystem debugging info to the console. +Debugging info on the probing and attachment of all SCSI devices will +be printed. +.Pp +Additional information can be requested by setting +.Em SCSIDEBUG_BUSES , +.Em SCSIDEBUG_LEVEL , +.Em SCSIDEBUG_LUNS +and +.Em SCSIDEBUG_TARGETS . +.It Cd option SCSIDEBUG_BUSES= Ns Ar value +Define which SCSI buses will print debug info. +Each bit enables debugging info for the corresponding bus. +e.g. a value of 0x1 enables debug info for bus 0. +.It Cd option SCSIDEBUG_LEVEL= Ns Ar value +Define which of the four levels of debugging info are printed. +Each bit enables a level, and multiple levels are specified by setting multiple +bits. +.Bd -literal -offset indent +0x0010 (SDEV_DB1) SCSI commands, errors, and data +0x0020 (SDEV_DB2) routine flow +0x0040 (SDEV_DB3) routine internals +0x0080 (SDEV_DB4) miscellaneous addition debugging +.Ed +.Pp +.Em SCSIDEBUG_LEVEL +defaults to a value of 0x0030 (SDEV_DB1|SDEV_DB2). +.It Cd option SCSIDEBUG_LUNS= Ns Ar value +Define which SCSI luns will print debug info. +Each bit enables debugging info for the corresponding lun. +.It Cd option SCSIDEBUG_TARGETS= Ns Ar value +Define which SCSI targets will print debug info. +Each bit enables debugging info for the corresponding target. +.It Cd option SCSITERSE +Terser SCSI error messages. +This omits the table for decoding ASC/ASCQ info, saving about 30KB. +.El +.Sh SYSTEM V IPC OPTIONS +.Bl -ohang +.It Cd option SEMMNI= Ns Ar value +Number of semaphore identifiers (also called semaphore handles +and semaphore sets) available in the system. +Default value is 10. +The kernel allocates memory for the control structures at startup, +so arbitrarily large values should be avoided. +.It Cd option SEMMNS= Ns Ar value +Maximum number of semaphores in all sets in the system. +Default value is 60. +.It Cd option SEMMNU= Ns Ar value +Maximum number of semaphore undo structures in the system. +Default value is 30. +.It Cd option SEMUME= Ns Ar value +Maximum number of per-process undo operation entries in the +system. +Semaphore undo operations are invoked by the kernel when +.Xr semop 2 +is called with the SEM_UNDO flag and the process holding +the semaphores terminates unexpectedly. +Default value is 10. +.It Cd option SHMMAXPGS= Ns Ar value +Sets the maximum number of +.At V +style shared memory pages that are available through the +.Xr shmget 2 +system call. +Default value is 1024 on most architectures. +See +.Pa /usr/include/machine/vmparam.h +for the default. +.It Cd option SYSVMSG +Includes support for +.At V +style message queues. +See +.Xr msgctl 2 , +.Xr msgget 2 , +.Xr msgrcv 2 , +.Xr msgsnd 2 . +.It Cd option SYSVSEM +Includes support for +.At V +style semaphores. +See +.Xr semctl 2 , +.Xr semget 2 , +.Xr semop 2 . +.It Cd option SYSVSHM +Includes support for +.At V +style shared memory. +See +.Xr shmat 2 , +.Xr shmctl 2 , +.Xr shmdt 2 , +.Xr shmget 2 . +.El +.Sh SEE ALSO +.Xr intro 4 , +.Xr files.conf 5 , +.Xr config 8 , +.Xr sysctl 8 +.Sh HISTORY +The +.Nm +man page first appeared in +.Ox 2.3 . |