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BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
.\" Copyright (c) 1992, 1993
.\" The Regents of the University of California. All rights reserved.
.\"
.\" This code is derived from software developed by the Computer Systems
.\" Engineering group at Lawrence Berkeley Laboratory under DARPA contract
.\" BG 91-66 and contributed to Berkeley.
.\"
.\" 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.
Renumber copyright clause 4 Renumber cluase 4 to 3, per what everybody else did when BSD granted them permission to remove clause 3. My insistance on keeping the same numbering for legal reasons is too pedantic, so give up on that point. Submitted by: Jan Schaumann <jschauma@stevens.edu> Pull Request: https://github.com/freebsd/freebsd/pull/96
2017-02-28 23:42:47 +00:00
.\" 3. Neither the name of the University nor the names of its contributors
BSD 4.4 Lite Lib Sources
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.\" may be used to endorse or promote products derived from this software
.\" without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
.\"
.\" @(#)kvm.3 8.1 (Berkeley) 6/4/93
$Id$ -> $FreeBSD$
1999-08-28 00:22:10 +00:00
.\" $FreeBSD$
BSD 4.4 Lite Lib Sources
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.\"
Remove kvm_getfiles(3) This libcall has been broken since (at least) r174989/8.0-RELEASE. Bump SHLIB_MAJOR for the change Differential Revision: https://reviews.freebsd.org/D6052 Relnotes: yes Reviewed by: jhb, markj Sponsored by: EMC / Isilon Storage Division
2016-04-30 09:21:13 +00:00
.Dd April 30, 2016
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
.Dt KVM 3
.Os
.Sh NAME
.Nm kvm
.Nd kernel memory interface
Introduce .Lb macro to libkvm manpages. Use .Pa macro for "enlighting" path
2000-04-22 16:10:12 +00:00
.Sh LIBRARY
.Lb libkvm
BSD 4.4 Lite Lib Sources
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.Sh DESCRIPTION
The
mdoc(7) police: Deal with self-xrefs.
2002-12-24 13:41:48 +00:00
.Nm
BSD 4.4 Lite Lib Sources
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library provides a uniform interface for accessing kernel virtual memory
Another round of spelling fixes.
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images, including live systems and crash dumps.
BSD 4.4 Lite Lib Sources
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Access to live systems is via
kvm(3): Mention that some of the functions use sysctl(3) instead of kmem. Additionally, because of sysctl(3) use (which is generally good), behaviour for crash dumps differs slightly from behaviour for live kernels and this will probably never be fixed entirely, so weaken that claim. MFC after: 1 week
2010-04-25 12:50:30 +00:00
.Xr sysctl 3
for some functions, and
Document that libkvm also uses /dev/kmem, to access KVM.
2004-03-26 08:03:53 +00:00
.Xr mem 4
and
.Xr kmem 4
kvm(3): Mention that some of the functions use sysctl(3) instead of kmem. Additionally, because of sysctl(3) use (which is generally good), behaviour for crash dumps differs slightly from behaviour for live kernels and this will probably never be fixed entirely, so weaken that claim. MFC after: 1 week
2010-04-25 12:50:30 +00:00
for other functions,
Another round of spelling fixes.
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while crash dumps can be examined via the core file generated by
BSD 4.4 Lite Lib Sources
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.Xr savecore 8 .
kvm(3): Mention that some of the functions use sysctl(3) instead of kmem. Additionally, because of sysctl(3) use (which is generally good), behaviour for crash dumps differs slightly from behaviour for live kernels and this will probably never be fixed entirely, so weaken that claim. MFC after: 1 week
2010-04-25 12:50:30 +00:00
The interface behaves similarly in both cases.
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
Memory can be read and written, kernel symbol addresses can be
looked up efficiently, and information about user processes can
be gathered.
.Pp
The .Fn function The .Fa argument
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The
BSD 4.4 Lite Lib Sources
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.Fn kvm_open
The .Fn function The .Fa argument
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function is first called to obtain a descriptor for all subsequent calls.
BSD 4.4 Lite Lib Sources
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.Sh COMPATIBILITY
Mechanically kill hard sentence breaks.
2004-07-02 23:52:20 +00:00
The kvm interface was first introduced in SunOS.
A considerable
BSD 4.4 Lite Lib Sources
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number of programs have been developed that use this interface,
making backward compatibility highly desirable.
In most respects, the Sun kvm interface is consistent and clean.
Accordingly, the generic portion of the interface (i.e.,
.Fn kvm_open ,
.Fn kvm_close ,
.Fn kvm_read ,
.Fn kvm_write ,
and
.Fn kvm_nlist )
mdoc(7) police: s/BSD/.Bx/ where appropriate.
2001-08-14 10:01:54 +00:00
has been incorporated into the
.Bx
Mechanically kill hard sentence breaks.
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interface.
Indeed, many kvm
BSD 4.4 Lite Lib Sources
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applications (i.e., debuggers and statistical monitors) use only
this subset of the interface.
.Pp
Mechanically kill hard sentence breaks.
2004-07-02 23:52:20 +00:00
The process interface was not kept.
This is not a portability
BSD 4.4 Lite Lib Sources
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issue since any code that manipulates processes is inherently
machine dependent.
.Pp
Finally, the Sun kvm error reporting semantics are poorly defined.
Consistently mark std(in|out|err) with .Dv, because that's how they are marked up in stdio(3), and because they are defined expressions of type "FILE *". Approved by: re
2002-12-04 18:57:46 +00:00
The library can be configured either to print errors to
.Dv stderr
automatically,
BSD 4.4 Lite Lib Sources
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or to print no error messages at all.
In the latter case, the nature of the error cannot be determined.
mdoc(7) police: s/BSD/.Bx/ where appropriate.
2001-08-14 10:01:54 +00:00
To overcome this, the
.Bx
interface includes a
BSD 4.4 Lite Lib Sources
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routine,
.Xr kvm_geterr 3 ,
to return (not print out) the error message
corresponding to the most recent error condition on the
given descriptor.
Add support to libkvm for reading vmcores from other architectures. - Add a kvaddr_type to represent kernel virtual addresses instead of unsigned long. - Add a struct kvm_nlist which is a stripped down version of struct nlist that uses kvaddr_t for n_value. - Add a kvm_native() routine that returns true if an open kvm descriptor is for a native kernel and memory image. - Add a kvm_open2() function similar to kvm_openfiles(). It drops the unused 'swapfile' argument and adds a new function pointer argument for a symbol resolving function. Native kernels still use _fdnlist() from libc to resolve symbols if a resolver function is not supplied, but cross kernels require a resolver. - Add a kvm_nlist2() function similar to kvm_nlist() except that it uses struct kvm_nlist instead of struct nlist. - Add a kvm_read2() function similar to kvm_read() except that it uses kvaddr_t instead of unsigned long for the kernel virtual address. - Add a new kvm_arch switch of routines needed by a vmcore backend. Each backend is responsible for implementing kvm_read2() for a given vmcore format. - Use libelf to read headers from ELF kernels and cores (except for powerpc cores). - Add internal helper routines for the common page offset hash table used by the minidump backends. - Port all of the existing kvm backends to implement a kvm_arch switch and to be cross-friendly by using private constants instead of ones that vary by platform (e.g. PAGE_SIZE). Static assertions are present when a given backend is compiled natively to ensure the private constants match the real ones. - Enable all of the existing vmcore backends on all platforms. This means that libkvm on any platform should be able to perform KVA translation and read data from a vmcore of any platform. Tested on: amd64, i386, sparc64 (marius) Differential Revision: https://reviews.freebsd.org/D3341
2015-11-27 18:58:26 +00:00
.Sh CROSS DEBUGGING
The
.Nm
library supports inspection of crash dumps from non-native kernels.
Only a limited subset of the kvm interface is supported for these dumps.
To inspect a crash dump of a non-native kernel,
the caller must provide a
.Fa resolver
function when opening a descriptor via
.Fn kvm_open2 .
In addition,
the kvm interface defines an integer type
.Pq Vt kvaddr_t
that is large enough to hold all valid addresses of all supported
architectures.
The interface also defines a new namelist structure type
.Pq Vt "struct kvm_nlist"
for use with
.Fn kvm_nlist2 .
To avoid address truncation issues,
the caller should use
.Fn kvm_nlist2
and
.Fn kvm_read2
in place of
.Fn kvm_nlist
and
.Fn kvm_read ,
respectively.
Finally, only a limited subset of operations are supported for non-native
crash dumps:
.Fn kvm_close ,
.Fn kvm_geterr
.Fn kvm_open2 ,
.Fn kvm_native ,
.Fn kvm_nlist2 ,
and
.Fn kvm_read2 .
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
.Sh SEE ALSO
.Xr kvm_close 3 ,
.Xr kvm_getargv 3 ,
.Xr kvm_getenvv 3 ,
.Xr kvm_geterr 3 ,
.Xr kvm_getloadavg 3 ,
.Xr kvm_getprocs 3 ,
Fixed unsorting of cross references in previous commit.
1999-01-23 07:34:56 +00:00
.Xr kvm_getswapinfo 3 ,
Add support to libkvm for reading vmcores from other architectures. - Add a kvaddr_type to represent kernel virtual addresses instead of unsigned long. - Add a struct kvm_nlist which is a stripped down version of struct nlist that uses kvaddr_t for n_value. - Add a kvm_native() routine that returns true if an open kvm descriptor is for a native kernel and memory image. - Add a kvm_open2() function similar to kvm_openfiles(). It drops the unused 'swapfile' argument and adds a new function pointer argument for a symbol resolving function. Native kernels still use _fdnlist() from libc to resolve symbols if a resolver function is not supplied, but cross kernels require a resolver. - Add a kvm_nlist2() function similar to kvm_nlist() except that it uses struct kvm_nlist instead of struct nlist. - Add a kvm_read2() function similar to kvm_read() except that it uses kvaddr_t instead of unsigned long for the kernel virtual address. - Add a new kvm_arch switch of routines needed by a vmcore backend. Each backend is responsible for implementing kvm_read2() for a given vmcore format. - Use libelf to read headers from ELF kernels and cores (except for powerpc cores). - Add internal helper routines for the common page offset hash table used by the minidump backends. - Port all of the existing kvm backends to implement a kvm_arch switch and to be cross-friendly by using private constants instead of ones that vary by platform (e.g. PAGE_SIZE). Static assertions are present when a given backend is compiled natively to ensure the private constants match the real ones. - Enable all of the existing vmcore backends on all platforms. This means that libkvm on any platform should be able to perform KVA translation and read data from a vmcore of any platform. Tested on: amd64, i386, sparc64 (marius) Differential Revision: https://reviews.freebsd.org/D3341
2015-11-27 18:58:26 +00:00
.Xr kvm_native 3 ,
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
.Xr kvm_nlist 3 ,
Add support to libkvm for reading vmcores from other architectures. - Add a kvaddr_type to represent kernel virtual addresses instead of unsigned long. - Add a struct kvm_nlist which is a stripped down version of struct nlist that uses kvaddr_t for n_value. - Add a kvm_native() routine that returns true if an open kvm descriptor is for a native kernel and memory image. - Add a kvm_open2() function similar to kvm_openfiles(). It drops the unused 'swapfile' argument and adds a new function pointer argument for a symbol resolving function. Native kernels still use _fdnlist() from libc to resolve symbols if a resolver function is not supplied, but cross kernels require a resolver. - Add a kvm_nlist2() function similar to kvm_nlist() except that it uses struct kvm_nlist instead of struct nlist. - Add a kvm_read2() function similar to kvm_read() except that it uses kvaddr_t instead of unsigned long for the kernel virtual address. - Add a new kvm_arch switch of routines needed by a vmcore backend. Each backend is responsible for implementing kvm_read2() for a given vmcore format. - Use libelf to read headers from ELF kernels and cores (except for powerpc cores). - Add internal helper routines for the common page offset hash table used by the minidump backends. - Port all of the existing kvm backends to implement a kvm_arch switch and to be cross-friendly by using private constants instead of ones that vary by platform (e.g. PAGE_SIZE). Static assertions are present when a given backend is compiled natively to ensure the private constants match the real ones. - Enable all of the existing vmcore backends on all platforms. This means that libkvm on any platform should be able to perform KVA translation and read data from a vmcore of any platform. Tested on: amd64, i386, sparc64 (marius) Differential Revision: https://reviews.freebsd.org/D3341
2015-11-27 18:58:26 +00:00
.Xr kvm_nlist2 3 ,
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
.Xr kvm_open 3 ,
Add support to libkvm for reading vmcores from other architectures. - Add a kvaddr_type to represent kernel virtual addresses instead of unsigned long. - Add a struct kvm_nlist which is a stripped down version of struct nlist that uses kvaddr_t for n_value. - Add a kvm_native() routine that returns true if an open kvm descriptor is for a native kernel and memory image. - Add a kvm_open2() function similar to kvm_openfiles(). It drops the unused 'swapfile' argument and adds a new function pointer argument for a symbol resolving function. Native kernels still use _fdnlist() from libc to resolve symbols if a resolver function is not supplied, but cross kernels require a resolver. - Add a kvm_nlist2() function similar to kvm_nlist() except that it uses struct kvm_nlist instead of struct nlist. - Add a kvm_read2() function similar to kvm_read() except that it uses kvaddr_t instead of unsigned long for the kernel virtual address. - Add a new kvm_arch switch of routines needed by a vmcore backend. Each backend is responsible for implementing kvm_read2() for a given vmcore format. - Use libelf to read headers from ELF kernels and cores (except for powerpc cores). - Add internal helper routines for the common page offset hash table used by the minidump backends. - Port all of the existing kvm backends to implement a kvm_arch switch and to be cross-friendly by using private constants instead of ones that vary by platform (e.g. PAGE_SIZE). Static assertions are present when a given backend is compiled natively to ensure the private constants match the real ones. - Enable all of the existing vmcore backends on all platforms. This means that libkvm on any platform should be able to perform KVA translation and read data from a vmcore of any platform. Tested on: amd64, i386, sparc64 (marius) Differential Revision: https://reviews.freebsd.org/D3341
2015-11-27 18:58:26 +00:00
.Xr kvm_open2 3 ,
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
.Xr kvm_openfiles 3 ,
.Xr kvm_read 3 ,
Add support to libkvm for reading vmcores from other architectures. - Add a kvaddr_type to represent kernel virtual addresses instead of unsigned long. - Add a struct kvm_nlist which is a stripped down version of struct nlist that uses kvaddr_t for n_value. - Add a kvm_native() routine that returns true if an open kvm descriptor is for a native kernel and memory image. - Add a kvm_open2() function similar to kvm_openfiles(). It drops the unused 'swapfile' argument and adds a new function pointer argument for a symbol resolving function. Native kernels still use _fdnlist() from libc to resolve symbols if a resolver function is not supplied, but cross kernels require a resolver. - Add a kvm_nlist2() function similar to kvm_nlist() except that it uses struct kvm_nlist instead of struct nlist. - Add a kvm_read2() function similar to kvm_read() except that it uses kvaddr_t instead of unsigned long for the kernel virtual address. - Add a new kvm_arch switch of routines needed by a vmcore backend. Each backend is responsible for implementing kvm_read2() for a given vmcore format. - Use libelf to read headers from ELF kernels and cores (except for powerpc cores). - Add internal helper routines for the common page offset hash table used by the minidump backends. - Port all of the existing kvm backends to implement a kvm_arch switch and to be cross-friendly by using private constants instead of ones that vary by platform (e.g. PAGE_SIZE). Static assertions are present when a given backend is compiled natively to ensure the private constants match the real ones. - Enable all of the existing vmcore backends on all platforms. This means that libkvm on any platform should be able to perform KVA translation and read data from a vmcore of any platform. Tested on: amd64, i386, sparc64 (marius) Differential Revision: https://reviews.freebsd.org/D3341
2015-11-27 18:58:26 +00:00
.Xr kvm_read2 3 ,
Document that libkvm also uses /dev/kmem, to access KVM.
2004-03-26 08:03:53 +00:00
.Xr kvm_write 3 ,
kvm(3): Mention that some of the functions use sysctl(3) instead of kmem. Additionally, because of sysctl(3) use (which is generally good), behaviour for crash dumps differs slightly from behaviour for live kernels and this will probably never be fixed entirely, so weaken that claim. MFC after: 1 week
2010-04-25 12:50:30 +00:00
.Xr sysctl 3 ,
Document that libkvm also uses /dev/kmem, to access KVM.
2004-03-26 08:03:53 +00:00
.Xr kmem 4 ,
.Xr mem 4
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