manuals: Fix "skipping end of block" .Ed errors

These were reported by `mandoc -T lint ...` as errors; this commit only
handles unnecessary .Ed commands.

The rendered output (in ascii and html) is

manuals: Fix "skipping end of block" .Ed errors

These were reported by `mandoc -T lint ...` as errors; this commit only
handles unnecessary .Ed commands.

The rendered output (in ascii and html) is not affected by this commit.

Signed-off-by: Graham Percival <gperciva@tarsnap.com>
Reviewed by: mhorne
MFC after: 3 days
Sponsored by: Tarsnap Backup Inc.
Pull Request: https://github.com/freebsd/freebsd-src/pull/1435

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ddb: Add CTF-based pretty printing

Add basic CTF support and a CTF-powered pretty-printer to ddb.

The db_ctf.* files expose a basic interface for fetching type
data for ELF symbols, interacting wit

ddb: Add CTF-based pretty printing

Add basic CTF support and a CTF-powered pretty-printer to ddb.

The db_ctf.* files expose a basic interface for fetching type
data for ELF symbols, interacting with the CTF string table,
and translating type identifiers to type data.

The db_pprint.c file uses those interfaces to implement
a pretty-printer for all kernel ELF symbols.
The pretty-printer works with symbol names and arbitrary addresses:
pprint struct thread 0xffffffff8194ad90

Pretty-printing currently only works after the root filesystem
gets mounted because the CTF info is not available during
early boot.

Differential Revision: https://reviews.freebsd.org/D37899
Approved by: markj (mentor)

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Remove $FreeBSD$: two-line nroff pattern

Remove /^\.\\"\n\.\\"\s*\$FreeBSD\$$\n/

ddb: have 'reset' command use normal reboot path

This conditionally gives all registered shutdown handlers a chance to
perform the reboot, with cpu_reset() being the fallback. The '\s'
modifier can

ddb: have 'reset' command use normal reboot path

This conditionally gives all registered shutdown handlers a chance to
perform the reboot, with cpu_reset() being the fallback. The '\s'
modifier can be used with the command to get the previous behaviour.

The motivation is that some platforms may not be able do anything
meaningful via cpu_reset(), due to a lack of standardized reset
mechanism and/or firmware shortcomings. However, they may have a
separate device driver attached that normally performs the reboot. Such
is the case for some versions of the Raspberry Pi, where reset via PSCI
fails, but the BCM2835 watchdog driver has a shutdown hook.

Reported by: bz
Reviewed by: markj (slightly earlier version)
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D37981

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ddb(4): document some missing commands

This is not exhaustive, just what I collected while working on
mac_ddb(4).

Reviewed by: pauamma, markj, jhb
MFC after: 1 week
Sponsored by: The FreeBSD Founda

ddb(4): document some missing commands

This is not exhaustive, just what I collected while working on
mac_ddb(4).

Reviewed by: pauamma, markj, jhb
MFC after: 1 week
Sponsored by: The FreeBSD Foundation (in part)
Differential Revision: https://reviews.freebsd.org/D37333

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ddb(4): misc updates

- Describe optional 'addr' argument to many show commands
- Remove obsolete commands (show cbstat)
- 'show jails' was renamed to 'show prison'
- Remove superfluous commentar

ddb(4): misc updates

- Describe optional 'addr' argument to many show commands
- Remove obsolete commands (show cbstat)
- 'show jails' was renamed to 'show prison'
- Remove superfluous commentary about sleepqueues
- Fix an xref to gdb(4)
- Fix issues reported by mandoc -Tlint
- Plus a couple other inaccuracies/inconsistencies

Reviewed by: pauamma, markj, jhb
MFC after: 1 week
Sponsored by: The FreeBSD Foundation (in part)
Differential Revision: https://reviews.freebsd.org/D37332

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Indicate which port gdb.1 and kgdb.1 come from.

Indicate that kgdb.1 is from ports/devel/gdb.

mac: add new mac_ddb(4) policy

Generally, access to the kernel debugger is considered to be unsafe from
a security perspective since it presents an unrestricted interface to
inspect or modify the sy

mac: add new mac_ddb(4) policy

Generally, access to the kernel debugger is considered to be unsafe from
a security perspective since it presents an unrestricted interface to
inspect or modify the system state, including sensitive data such as
signing keys.

However, having some access to debugger functionality on production
systems may be useful in determining the cause of a panic or hang.
Therefore, it is desirable to have an optional policy which allows
limited use of ddb(4) while disabling the functionality which could
reveal system secrets.

This loadable MAC module allows for the use of some ddb(4) commands
while preventing the execution of others. The commands have been broadly
grouped into three categories:
- Those which are 'safe' and will not emit sensitive data (e.g. trace).
Generally, these commands are deterministic and don't accept
arguments.
- Those which are definitively unsafe (e.g. examine <addr>, search
<addr> <value>)
- Commands which may be safe to execute depending on the arguments
provided (e.g. show thread <addr>).

Safe commands have been flagged as such with the DB_CMD_MEMSAFE flag.

Commands requiring extra validation can provide a function to do so.
For example, 'show thread <addr>' can be used as long as addr can be
checked against the system's list of process structures.

The policy also prevents debugger backends other than ddb(4) from
executing, for example gdb(4).

Reviewed by: markj, pauamma_gundo.com (manpages)
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D35371

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Fix mdoc macro usage and style in section 4 manpages.

ddb(4): improve wording

Incorporate feedback overlooked in revew by wblock@

Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D4860

ddb: enable the use of ^C and ^S/^Q

This lets one interrupt DDB's output, which is useful if paging is
disabled and the output device is slow.

This follows a previous implementation in svn r311952

ddb: enable the use of ^C and ^S/^Q

This lets one interrupt DDB's output, which is useful if paging is
disabled and the output device is slow.

This follows a previous implementation in svn r311952 / git
5fddef79998678d256ba30316353393b4d8ebb32 which was reverted because it
broke DDB type-ahead.

Now, try this again, but with a 512-byte type-ahead buffer. While there
is buffer space, control input is handled and non-control input is
buffered. When the buffer is exhausted, the default is to print a
warning and drop further non-control input in order to continue handling
control input. sysctl debug.ddb.prioritize_control_input can be set to
0 to instead preserve all input but lose immediate handling of control
input. This could for example effect pasting of a large script into the
ddb console.

Suggested by: Anton Rang <rang@acm.org>
Reviewed by: markj
Discussed with: imp
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D28676

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man: remove stale references to ndis(4)

The latter has been removed in bfc99943b04b46a6c1c885ce7bcc6f235b7422aa.

ddb: add ability to print user registers

The debugger is always entered after some kind of kernel trap, often a
breakpoint in kdb_enter(). This means that the most recent trapframe
will include kern

ddb: add ability to print user registers

The debugger is always entered after some kind of kernel trap, often a
breakpoint in kdb_enter(). This means that the most recent trapframe
will include kernel state at the time of the trap, when often it is
desirable to the developer to view the contents of the previous
trapframe. This trapframe often corresponds to the entry from userspace.

The ddb(4) man page claims the ability to display user register state
via the 'u' modifier to `show registers`, but this appears untrue. It is
not obvious from a quick search of the history when this feature was
added, or when it was removed. (Re)implement this feature in
db_show_regs, noting that it is not necessarily populated with userspace
state.

Reviewed by: jhb (earlier version), markj, bcr (manpages)
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D27705

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Add an option for entering KDB on recursive panics

There are many cases where one would choose avoid entering the debugger
on a normal panic, opting instead to reboot and possibly save a kernel
dump

Add an option for entering KDB on recursive panics

There are many cases where one would choose avoid entering the debugger
on a normal panic, opting instead to reboot and possibly save a kernel
dump. However, recursive kernel panics are an unusual case that might
warrant attention from a human, so provide a secondary tunable,
debug.debugger_on_recursive_panic, to allow entering the debugger only
when this occurs.

For for simplicity in maintaining existing behaviour, the tunable
defaults to zero.

Reviewed by: cem, markj
Sponsored by: NetApp, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D27271

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Fix a bunch of mdoc issues found by mandoc -Tlint.

Merge ^/head r357662 through r357854.

Remove sparc64 specific bits of the man pages.

Implement NetGDB(4)

NetGDB(4) is a component of a system using a panic-time network stack to
remotely debug crashed FreeBSD kernels over the network, instead of
traditional serial interfaces.

There

Implement NetGDB(4)

NetGDB(4) is a component of a system using a panic-time network stack to
remotely debug crashed FreeBSD kernels over the network, instead of
traditional serial interfaces.

There are three pieces in the complete NetGDB system.

First, a dedicated proxy server must be running to accept connections from
both NetGDB and gdb(1), and pass bidirectional traffic between the two
protocols.

Second, the NetGDB client is activated much like ordinary 'gdb' and
similarly to 'netdump' in ddb(4) after a panic. Like other debugnet(4)
clients (netdump(4)), the network interface on the route to the proxy server
must be online and support debugnet(4).

Finally, the remote (k)gdb(1) uses 'target remote <proxy>:<port>' (like any
other TCP remote) to connect to the proxy server.

The NetGDB v1 protocol speaks the literal GDB remote serial protocol, and
uses a 1:1 relationship between GDB packets and sequences of debugnet
packets (fragmented by MTU). There is no encryption utilized to keep
debugging sessions private, so this is only appropriate for local
segments or trusted networks.

Submitted by: John Reimer <john.reimer AT emc.com> (earlier version)
Discussed some with: emaste, markj
Relnotes: sure
Differential Revision: https://reviews.freebsd.org/D21568

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debugnet(4): Infer non-server connection parameters

Loosen requirements for connecting to debugnet-type servers. Only require a
destination address; the rest can theoretically be inferred from the

debugnet(4): Infer non-server connection parameters

Loosen requirements for connecting to debugnet-type servers. Only require a
destination address; the rest can theoretically be inferred from the routing
table.

Relax corresponding constraints in netdump(4) and move ifp validation to
debugnet connection time.

Submitted by: John Reimer <john.reimer AT emc.com> (earlier version)
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D21482

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Add ddb(4) 'netdump' command to netdump a core without preconfiguration

Add a 'X -s <server> -c <client> [-g <gateway>] -i <interface>' subroutine
to the generic debugnet code. The imagined use is

Add ddb(4) 'netdump' command to netdump a core without preconfiguration

Add a 'X -s <server> -c <client> [-g <gateway>] -i <interface>' subroutine
to the generic debugnet code. The imagined use is both netdump, shown here,
and NetGDB (vaporware). It uses the ddb(4) lexer, with some new extensions,
to parse out IPv4 addresses.

'Netdump' uses the generic debugnet routine to load a configuration and
start a dump, without any netdump configuration prior to panic.

Loosely derived from work by: John Reimer <john.reimer AT emc.com>
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D21460

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ddb: Add CSV option, sorting to 'show (malloc|uma)'

Add /i option for machine-parseable CSV output. This allows ready copy/
pasting into more sophisticated tooling outside of DDB.

Add total zone s

ddb: Add CSV option, sorting to 'show (malloc|uma)'

Add /i option for machine-parseable CSV output. This allows ready copy/
pasting into more sophisticated tooling outside of DDB.

Add total zone size ("Memory Use") as a new column for UMA.

For both, sort the displayed list on size (print the largest zones/types
first). This is handy for quickly diagnosing "where has my memory gone?" at
a high level.

Submitted by: Emily Pettigrew <Emily.Pettigrew AT isilon.com> (earlier version)
Sponsored by: Dell EMC Isilon

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Merge ^/head r352105 through r352307.

ddb(4): Add 'show route <dest>' and 'show routetable [<af>]'

These commands show the route resolved for a specified destination, or
print out the entire routing table for a given address family (or

ddb(4): Add 'show route <dest>' and 'show routetable [<af>]'

These commands show the route resolved for a specified destination, or
print out the entire routing table for a given address family (or all
families, if none is explicitly provided).

Discussed with: emaste
Differential Revision: https://reviews.freebsd.org/D21510

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Merge ^/head r340918 through r341763.