proc: Remove kernel stack swapping support, part 6

- Remove most checks of the P_INMEM flag.
- Some uses remain since a few userspace tools, e.g., ps(1) and top(1)
expect the flag to be set. Thes

proc: Remove kernel stack swapping support, part 6

- Remove most checks of the P_INMEM flag.
- Some uses remain since a few userspace tools, e.g., ps(1) and top(1)
expect the flag to be set. These can be cleaned up but the code has
most likely been copy-pasted elsewhere and while linger for a long
time.

Tested by: pho
Reviewed by: alc, imp, kib
Differential Revision: https://reviews.freebsd.org/D46117

show more ...

ddb: make db_error reliably no-return

Most code assumes db_error does not return, but according to
kdb_reenter_silent, there may be cases where it could. Instead, panic
if kdb_reenter_silent return

ddb: make db_error reliably no-return

Most code assumes db_error does not return, but according to
kdb_reenter_silent, there may be cases where it could. Instead, panic
if kdb_reenter_silent returns and mark the routine as __dead2. This
addresses gcc warnings.

Reported by: GCC -Wmaybe-uninitialized
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D45918

show more ...

sys/ddb: Add hardware breakpoint support to ddb

As with hardware watchpoints add support for hardware breakpoints. The
command is only enabled on architectures that report support for them.
Currentl

sys/ddb: Add hardware breakpoint support to ddb

As with hardware watchpoints add support for hardware breakpoints. The
command is only enabled on architectures that report support for them.
Currently no architectures do, however arm64 will add support in a
future change.

Reviewed by: jhb (earlier version)
Sponsored by: Arm Ltd
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D22191

show more ...

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)

show more ...

sys: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remov

sys: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

show more ...

sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\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

show more ...

ddb: Don't flag breakpoint/watchpoint commands as MEMSAFE

They could potentially be abused to overwrite kernel memory, so
shouldn't be accessible when mac_ddb is loaded.

Reviewed by: mhorne
Fixes:

ddb: Don't flag breakpoint/watchpoint commands as MEMSAFE

They could potentially be abused to overwrite kernel memory, so
shouldn't be accessible when mac_ddb is loaded.

Reviewed by: mhorne
Fixes: bc4ea61d55cb ("ddb: tag core commands with DB_CMD_MEMSAFE")
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D37105

show more ...

mac: kdb/ddb framework hooks

Add three simple hooks to the debugger allowing for a loaded MAC policy
to intervene if desired:
1. Before invoking the kdb backend
2. Before ddb command registration

mac: kdb/ddb framework hooks

Add three simple hooks to the debugger allowing for a loaded MAC policy
to intervene if desired:
1. Before invoking the kdb backend
2. Before ddb command registration
3. Before ddb command execution

We extend struct db_command with a private pointer and two flag bits
reserved for policy use.

Reviewed by: markj
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D35370

show more ...

ddb: tag core commands with DB_CMD_MEMSAFE

Those which are statically defined in db_command.c.

Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.

ddb: tag core commands with DB_CMD_MEMSAFE

Those which are statically defined in db_command.c.

Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D35584

show more ...

ddb: annotate some commands with DB_CMD_MEMSAFE

This is not completely exhaustive, but covers a large majority of
commands in the tree.

Reviewed by: markj
Sponsored by: Juniper Networks, Inc.
Spons

ddb: annotate some commands with DB_CMD_MEMSAFE

This is not completely exhaustive, but covers a large majority of
commands in the tree.

Reviewed by: markj
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D35583

show more ...

db_command.c: use designated initializers

Provide separate helper macros for regular commands and next-level table
commands as they are mutually exclusive. This ensures proper
initialization of each

db_command.c: use designated initializers

Provide separate helper macros for regular commands and next-level table
commands as they are mutually exclusive. This ensures proper
initialization of each element and allows us to exclude some redundant
fields, such as specifying .more = NULL for every regular command.

Reviewed by: markj, jhb
MFC after: 3 days
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D35580

show more ...

db_command.c: style

Reviewed by: jhb
MFC after: 3 days
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D35368

ddb: namespacing of struct command

'command' is too generic for something specific to the kernel debugger;
change this so it is less likely to collide with local variable names.
Also rename struct c

ddb: namespacing of struct command

'command' is too generic for something specific to the kernel debugger;
change this so it is less likely to collide with local variable names.
Also rename struct command_table to struct db_command_table.

Reviewed by: markj
MFC after: 1 week
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D35367

show more ...

ddb: reliably fail with ambiguous commands

db_cmd_match had an even/odd bug, where if a third command was partially
matched (or any odd number greater than one) the search result would be
set back f

ddb: reliably fail with ambiguous commands

db_cmd_match had an even/odd bug, where if a third command was partially
matched (or any odd number greater than one) the search result would be
set back from CMD_AMBIGUOUS to CMD_FOUND, causing the last command in
the list to be executed instead of failing the match.

Reported by: mlaier
Reviewed by: markj, mlaier, vangyzen
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D28659

show more ...

Use atomic loads/stores when updating td->td_state

KCSAN complains about racy accesses in the locking code. Those races are
fine since they are inside a TD_SET_RUNNING() loop that expects the value

Use atomic loads/stores when updating td->td_state

KCSAN complains about racy accesses in the locking code. Those races are
fine since they are inside a TD_SET_RUNNING() loop that expects the value
to be changed by another CPU.

Use relaxed atomic stores/loads to indicate that this variable can be
written/read by multiple CPUs at the same time. This will also prevent
the compiler from doing unexpected re-ordering.

Reported by: GENERIC-KCSAN
Test Plan: KCSAN no longer complains, kernel still runs fine.
Reviewed By: markj, mjg (earlier version)
Differential Revision: https://reviews.freebsd.org/D28569

show more ...

Use kdb_thr_* to iterate over threads consistently in DDB.

The "findstack", "show all trace", and "show active trace" commands
were iterating over allproc to enumerate threads. This missed threads

Use kdb_thr_* to iterate over threads consistently in DDB.

The "findstack", "show all trace", and "show active trace" commands
were iterating over allproc to enumerate threads. This missed threads
executing in exit1() after being removed from allproc.

Reviewed by: kib
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D27829

show more ...

Don't check P_INMEM in kdb_thr_*().

Not all debugger operations that enumerate threads require thread
stacks to be resident in memory to be useful. Instead, push P_INMEM
checks (if needed) into cal

Don't check P_INMEM in kdb_thr_*().

Not all debugger operations that enumerate threads require thread
stacks to be resident in memory to be useful. Instead, push P_INMEM
checks (if needed) into callers.

Reviewed by: kib
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D27827

show more ...

MFHead @348740

Sponsored by: The FreeBSD Foundation

Extract eventfilter declarations to sys/_eventfilter.h

This allows replacing "sys/eventfilter.h" includes with "sys/_eventfilter.h"
in other header files (e.g., sys/{bus,conf,cpu}.h) and reduces hea

Extract eventfilter declarations to sys/_eventfilter.h

This allows replacing "sys/eventfilter.h" includes with "sys/_eventfilter.h"
in other header files (e.g., sys/{bus,conf,cpu}.h) and reduces header
pollution substantially.

EVENTHANDLER_DECLARE and EVENTHANDLER_LIST_DECLAREs were moved out of .c
files into appropriate headers (e.g., sys/proc.h, powernv/opal.h).

As a side effect of reduced header pollution, many .c files and headers no
longer contain needed definitions. The remainder of the patch addresses
adding appropriate includes to fix those files.

LOCK_DEBUG and LOCK_FILE_LINE_ARG are moved to sys/_lock.h, as required by
sys/mutex.h since r326106 (but silently protected by header pollution prior
to this change).

No functional change (intended). Of course, any out of tree modules that
relied on header pollution for sys/eventhandler.h, sys/lock.h, or
sys/mutex.h inclusion need to be fixed. __FreeBSD_version has been bumped.

show more ...

Merge ^/head r339015 through r339669.

ddb: Enable 'thread <address>'

Currently, the 'thread' command (to switch the debugger to another thread)
only accepts decimal-encoded tids. Use the same parsing logic as 'show
thread <arg>' to acc

ddb: Enable 'thread <address>'

Currently, the 'thread' command (to switch the debugger to another thread)
only accepts decimal-encoded tids. Use the same parsing logic as 'show
thread <arg>' to accept hex-encoded thread pointers in addition to
decimal-encoded tids.

Document the 'thread' command in ddb.4 and expand the 'show thread'
documentation to cover the tid usage.

Reported by: bwidawsk
Reviewed by: bwidawsk (earlier version), kib (earlier version), markj
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D16962

show more ...

Restore db_radix on parse error, otherwise we'll silently change it to
10 on a botched trace command.

SPDX: Consider code from Carnegie-Mellon University.

Interesting cases, most likely from CMU Mach sources.

Make kdb_reenter() silent when explicitly called from db_error().
This removes the useless backtrace on various ddb(4) user errors.

Reviewed by: jhb@
Obtained from: CheriBSD
MFC after: 2 weeks
Spons

Make kdb_reenter() silent when explicitly called from db_error().
This removes the useless backtrace on various ddb(4) user errors.

Reviewed by: jhb@
Obtained from: CheriBSD
MFC after: 2 weeks
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D13212

show more ...