Commit Graph

53 Commits

Author SHA1 Message Date
Roger Pau Monné
c98a2727cc ddb: allow specifying the exact address of the symtab and strtab
When the FreeBSD kernel is loaded from Xen the symtab and strtab are
not loaded the same way as the native boot loader. This patch adds
three new global variables to ddb that can be used to specify the
exact position and size of those tables, so they can be directly used
as parameters to db_add_symbol_table. A new helper is introduced, so callers
that used to set ksym_start and ksym_end can use this helper to set the new
variables.

It also adds support for loading them from the Xen PVH port, that was
previously missing those tables.

Sponsored by: Citrix Systems R&D
Reviewed by:	kib

ddb/db_main.c:
 - Add three new global variables: ksymtab, kstrtab, ksymtab_size that
   can be used to specify the position and size of the symtab and
   strtab.
 - Use those new variables in db_init in order to call db_add_symbol_table.
 - Move the logic in db_init to db_fetch_symtab in order to set ksymtab,
   kstrtab, ksymtab_size from ksym_start and ksym_end.

ddb/ddb.h:
 - Add prototype for db_fetch_ksymtab.
 - Declate the extern variables ksymtab, kstrtab and ksymtab_size.

x86/xen/pv.c:
 - Add support for finding the symtab and strtab when booted as a Xen
   PVH guest. Since Xen loads the symtab and strtab as NetBSD expects
   to find them we have to adapt and use the same method.

amd64/amd64/machdep.c:
arm/arm/machdep.c:
i386/i386/machdep.c:
mips/mips/machdep.c:
pc98/pc98/machdep.c:
powerpc/aim/machdep.c:
powerpc/booke/machdep.c:
sparc64/sparc64/machdep.c:
 - Use the newly introduced db_fetch_ksymtab in order to set ksymtab,
   kstrtab and ksymtab_size.
2014-09-25 08:28:10 +00:00
Pedro F. Giffuni
1285b2d147 ddb: Minor style cleanups.
#define should be followed by tab.

MFC after:	1 week
2014-03-31 16:37:41 +00:00
Konstantin Belousov
9ab83ecbcb Add 'findstack' ddb command to search either the thread kernel stack
or cached stack containing the specified kernel virtual address.

Discussed with:	pho
MFC after:	1 week
2011-12-16 11:44:20 +00:00
Attilio Rao
3caaaae046 There is not a good reason to have a different prototype for db_printf()
when compared to printf().
Unify it by returning the number of characters displayed for db_printf()
as well.

MFC after:	7 days
2010-05-11 17:01:14 +00:00
Robert Watson
eddfbb763d Build on Jeff Roberson's linker-set based dynamic per-CPU allocator
(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator.  Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...).  This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.

Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack.  Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory.  Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.

Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy.  Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address.  When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.

This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.

Bump __FreeBSD_version and update UPDATING.

Portions submitted by:  bz
Reviewed by:            bz, zec
Discussed with:         gnn, jamie, jeff, jhb, julian, sam
Suggested by:           peter
Approved by:            re (kensmith)
2009-07-14 22:48:30 +00:00
Sam Leffler
39297ba455 Make ddb command registration dynamic so modules can extend
the command set (only so long as the module is present):
o add db_command_register and db_command_unregister to add and remove
  commands, respectively
o replace linker sets with SYSINIT's (and SYSUINIT's) that register
  commands
o expose 3 list heads: db_cmd_table, db_show_table, and db_show_all_table
  for registering top-level commands, show operands, and show all operands,
  respectively

While here also:
o sort command lists
o add DB_ALIAS, DB_SHOW_ALIAS, and DB_SHOW_ALL_ALIAS to add aliases
  for existing commands
o add "show all trace" as an alias for "show alltrace"
o add "show all locks" as an alias for "show alllocks"

Submitted by:	Guillaume Ballet <gballet@gmail.com> (original version)
Reviewed by:	jhb
MFC after:	1 month
2008-09-15 22:45:14 +00:00
Sam Leffler
9e340a6190 enable dynamic addition of "show all" commands
MFC after:	3 weeks
2008-03-25 20:36:32 +00:00
Robert Watson
618c7db30a Add textdump(4) facility, which provides an alternative form of kernel
dump using mechanically generated/extracted debugging output rather than
a simple memory dump.  Current sources of debugging output are:

- DDB output capture buffer, if there is captured output to save
- Kernel message buffer
- Kernel configuration, if included in kernel
- Kernel version string
- Panic message

Textdumps are stored in swap/dump partitions as with regular dumps, but
are laid out as ustar files in order to allow multiple parts to be stored
as a stream of sequentially written blocks.  Blocks are written out in
reverse order, as the size of a textdump isn't known a priori.  As with
regular dumps, they will be extracted using savecore(8).

One new DDB(4) command is added, "textdump", which accepts "set",
"unset", and "status" arguments.  By default, normal kernel dumps are
generated unless "textdump set" is run in order to schedule a textdump.
It can be canceled using "textdump unset" to restore generation of a
normal kernel dump.

Several sysctls exist to configure aspects of textdumps;
debug.ddb.textdump.pending can be set to check whether a textdump is
pending, or set/unset in order to control whether the next kernel dump
will be a textdump from userspace.

While textdumps don't have to be generated as a result of a DDB script
run automatically as part of a kernel panic, this is a particular useful
way to use them, as instead of generating a complete memory dump, a
simple transcript of an automated DDB session can be captured using the
DDB output capture and textdump facilities.  This can be used to
generate quite brief kernel bug reports rich in debugging information
but not dependent on kernel symbol tables or precisely synchronized
source code.  Most textdumps I generate are less than 100k including
the full message buffer.  Using textdumps with an interactive debugging
session is also useful, with capture being enabled/disabled in order to
record some but not all of the DDB session.

MFC after:	3 months
2007-12-26 11:32:33 +00:00
Robert Watson
c9b0cc3b96 Add a simple scripting facility to DDB(4), allowing the user to
define a set of named scripts.  Each script consists of a list of DDB
commands separated by ";"s that will be executed verbatim.  No higher
level language constructs, such as branching, are provided for:
scripts are executed by sequentially injecting commands into the DDB
input buffer.

Four new commands are present in DDB: "run" to run a specific script,
"script" to define or print a script, "scripts" to list currently
defined scripts, and "unscript" to delete a script, modeled on shell
alias commands.  Scripts may also be manipulated using sysctls in the
debug.ddb.scripting MIB space, although users will prefer to use the
soon-to-be-added ddb(8) tool for usability reasons.

Scripts with certain names are automatically executed on various DDB
events, such as entering the debugger via a panic, a witness error,
watchdog, breakpoint, sysctl, serial break, etc, allowing customized
handling.

MFC after:	3 months
2007-12-26 09:33:19 +00:00
Robert Watson
086fec574e Add a new DDB(4) facility, output capture. Input and output from DDB may be
captured to a memory buffer for later inspection using sysctl(8), or in the
future, to a textdump.

A new DDB command, "capture", is added, which accepts arguments "on", "off",
"reset", and "status".

A new DDB sysctl tree, debug.ddb.capture, is added, which can be used to
resize the capture buffer and extract buffer contents.

MFC after:	3 months
2007-12-25 23:06:51 +00:00
John Baldwin
19e9205a23 Simplify the pager support in DDB. Allowing different db commands to
install custom pager functions didn't actually happen in practice (they
all just used the simple pager and passed in a local quit pointer).  So,
just hardcode the simple pager as the only pager and make it set a global
db_pager_quit flag that db commands can check when the user hits 'q' (or a
suitable variant) at the pager prompt.  Also, now that it's easy to do so,
enable paging by default for all ddb commands.  Any command that wishes to
honor the quit flag can do so by checking db_pager_quit.  Note that the
pager can also be effectively disabled by setting $lines to 0.

Other fixes:
- 'show idt' on i386 and pc98 now actually checks the quit flag and
  terminates early.
- 'show intr' now actually checks the quit flag and terminates early.
2006-07-12 21:22:44 +00:00
John Baldwin
d605beaaa8 Add two helper functions: db_lookup_thread() and db_lookup_proc(). They
take the addr value passed to a ddb command and attempt to use it to
lookup a struct thread * or struct proc *, respectively.  Each function
first reparses the passed in value as if it was an ID entered in base 10.
For threads the ID is treated as a thread ID, for proceses the ID is
treated as a PID.  If a thread or proc matching the ID is found, it is
returned.  For db_lookup_thread(), if the check_pid argument is true and
it didn't find a thread with a matching thread ID, it will treat the ID as
a PID and look for a matching process.  If it finds one it returns the
first thread in the process.  If none of the ID lookups succeeded, then
the functions assume that the passed in address is a thread or proc
pointer, respectively.  This allows one to use tids, pids, or structure
pointers interchangeably in ddb functions that want to lookup threads or
processes if desired.
2006-04-25 20:22:48 +00:00
John Baldwin
e1e31c0e43 Clean up the way we handle auxiliary commands for a given ddb command
table.  Previously, the ddb code knew of each linker set of auxiliary
commands and which explicit command list they were tied to.  These changes
add a simple command_table struct that contains both the static list of
commands and the pointers for any auxiliary linker set of additional
commands.  This also makes it possible for other arbitrary command tables
to be defined in other parts of the kernel w/o having to edit ddb itself.

The DB_SET macro has also been trimmed down to just creating an entry in
a linker set.  A new DB_FUNC macro does what the old DB_SET did which is
to not only add an entry to the linker set but also to include a function
prototype for the function being added.  With these changes, it's now also
possible to create aliases for ddb functions using DB_SET() directly if
desired.
2006-03-07 22:17:06 +00:00
Marcel Moolenaar
216e80c2ba Move the prototypes of db_md_set_watchpoint(), db_md_clr_watchpoint()
and db_md_list_watchpoints() to ddb/ddb.h.
2005-09-10 03:01:25 +00:00
Marcel Moolenaar
a2aeb24eff Implement functions calls from within DDB on ia64. On ia64 a function
pointer doesn't point to the first instruction of that function, but
rather to a descriptor. The descriptor has the address of the first
instruction, as well as the value of the global pointer. The symbol
table doesn't know anything about descriptors, so if you lookup the
name of a function you get the address of the first instruction. The
cast from the address, which is the result of the symbol lookup, to a
function pointer as is done in db_fncall is therefore invalid.
Abstract this detail behind the DB_CALL macro. By default DB_CALL is
defined as db_fncall_generic, which yields the old behaviour. On ia64
the macro is defined as db_fncall_ia64, in which a descriptor is
constructed to yield a valid function pointer.

While here, introduce DB_MAXARGS. DB_MAXARGS replaces the existing
(local) MAXARGS. The DB_MAXARGS macro can be defined by platforms to
create a convenient maximum. By default this will be the legacy 10.
On ia64 we define this macro to be 8, for 8 is the maximum number of
arguments that can be passed in registers. This avoids having to
implement spilling of arguments on the memory stack.

Approved by: re (dwhite)
2005-07-02 23:52:37 +00:00
Paul Saab
8cb038b4b2 Don't enter the debugger if KDB_UNATTENDED is set or if
debug.debugger_on_panic=0.

MFC after:	2 weeks
2005-04-20 20:52:46 +00:00
John Baldwin
d39d4a6e64 - Change the ddb paging "support" to use a variable (db_lines_per_page) to
control the number of lines per page rather than a constant.  The variable
  can be examined and changed in ddb as '$lines'.  Setting the variable to
  0 will effectively turn off paging.
- Change db_putchar() to force out pending whitespace before outputting
  newlines and carriage returns so that one can rub out content on the
  current line via '\r     \r' type strings.
- Change the simple pager to rub out the --More-- prompt explicitly when
  the routine exits.
- Add some aliases to the simple pager to make it more compatible with
  more(1): 'e' and 'j' do a single line.  'd' does half a page, and
  'f' does a full page.

MFC after:	1 month
Inspired by:	kris
2004-11-01 22:15:15 +00:00
Marcel Moolenaar
fd32d93b97 Unify db_stack_trace_cmd(). All it did was look up the thread given
the thread ID and call db_trace_thread().
Since arm has all the logic in db_stack_trace_cmd(), rename the
new DB_COMMAND function to db_stack_trace to avoid conflicts on
arm.
While here, have db_stack_trace parse its own arguments so that
we can use a more natural radix for IDs. If the ID is not a thread
ID, or more precisely when no thread exists with the ID, try if
there's a process with that ID and return the first thread in it.
This makes it easier to print stack traces from the ps output.

requested by: rwatson@
tested on: amd64, i386, ia64
2004-07-21 05:07:09 +00:00
Marcel Moolenaar
37224cd3fc Mega update for the KDB framework: turn DDB into a KDB backend.
Most of the changes are a direct result of adding thread awareness.
Typically, DDB_REGS is gone. All registers are taken from the
trapframe and backtraces use the PCB based contexts. DDB_REGS was
defined to be a trapframe on all platforms anyway.
Thread awareness introduces the following new commands:
	thread X	switch to thread X (where X is the TID),
	show threads	list all threads.

The backtrace code has been made more flexible so that one can
create backtraces for any thread by giving the thread ID as an
argument to trace.

With this change, ia64 has support for breakpoints.
2004-07-10 23:47:20 +00:00
John Baldwin
1e16f6098b Add a one-shot callout facility to db_printf() that executes the registered
callout when a specified number of lines have been output.  This can be
used to implement pagers for ddb commands that output a lot of text.  A
simple paging function is included that automatically rearms itself when
fired.

Reviewed by:	bde, julian
2003-07-31 17:27:52 +00:00
Poul-Henning Kamp
029f0b69a4 Change "dev_t gdbdev" to "void *gdb_arg", some possible paths for GDB
will not have a dev_t.
2003-02-16 19:22:21 +00:00
Jake Burkholder
d43f696c1c Revert previous and move the prototype for db_alt_break to ddb.h.
Requested by:	bde (I think)
2002-12-31 18:30:53 +00:00
Julian Elischer
93a7aa79d6 Add code to ddb to allow backtracing an arbitrary thread.
(show thread {address})

Remove the IDLE kse state and replace it with a change in
the way threads sahre KSEs. Every KSE now has a thread, which is
considered its "owner" however a KSE may also be lent to other
threads in the same group to allow completion of in-kernel work.
n this case the owner remains the same and the KSE will revert to the
owner when the other work has been completed.

All creations of upcalls etc. is now done from
kse_reassign() which in turn is called from mi_switch or
thread_exit(). This means that special code can be removed from
msleep() and cv_wait().

kse_release() does not leave a KSE with no thread any more but
converts the existing thread into teh KSE's owner, and sets it up
for doing an upcall. It is just inhibitted from being scheduled until
there is some reason to do an upcall.

Remove all trace of the kse_idle queue since it is no-longer needed.
"Idle" KSEs are now on the loanable queue.
2002-12-28 01:23:07 +00:00
Mark Murray
bda9921d3f Constify to kill some warnings. 2002-09-21 17:29:36 +00:00
John Baldwin
c79408a059 Implement db_print_backtrace() if DDB is compiled into the kernel. This
MD function is just a wrapper around db_stack_trace_cmd() that prints out
a backtrace of curthread.  Currently, this function is only implemented
on i386 and alpha (and the alpha version isn't quite tested yet, will do
that in a bit).  Other changes:

- For i386, fix a bug in the raw frame address case.  The eip we extract
  from the passed in frame address does not match the frame we received.
  Thus, instead of printing a bogus frame with the wrong eip, go ahead
  and advance frame down to the same frame as the eip we are using.
- For alpha, attempt to add a way of doing a raw trace for alpha.  Instead
  of passing a frame address in 'addr', pass in a pointer to a structure
  containing PC and KSP and use those to start the backtrace.  The alpha
  db_print_backtrace() uses asm to read in the current PC and KSP values
  into such a request.

Tested on:	i386
Requested by:	many
2002-09-19 18:46:29 +00:00
Justin T. Gibbs
7102c89a86 Allow DB_SET() to set all fields in the ddb command structure. This
allows external ddb commands to do anyting an internal command can
do, including non-standard argument parsing if desired.
2002-06-05 19:00:02 +00:00
Bruce Evans
763df83622 Fixed some style bugs in the removal of __P(()). Continuation lines
were not outdented to preserve non-KNF lining up of code with parentheses.
Switch to KNF formatting.
2002-03-23 11:53:03 +00:00
Alfred Perlstein
14e10f9952 Remove __P. 2002-03-20 05:14:42 +00:00
Brian S. Dean
17bbfb5897 Add 'hwatch' and 'dhwatch' ddb commands analogous to 'watch' and
'dwatch'.  The new commands install hardware watchpoints if supported
by the architecture and if there are enough registers to cover the
desired memory area.

No objection by: audit@, hackers@

MFC after: 2 weeks
2001-07-11 03:15:25 +00:00
Kazutaka YOKOTA
35e61cbd71 Add a new mechanism, cndbctl(), to tell the console driver that
ddb is entered.  Don't refer to `in_Debugger' to see if we
are in the debugger.  (The variable used to be static in Debugger()
and wasn't updated if ddb is entered via traps and panic anyway.)

- Don't refer to `in_Debugger'.
- Add `db_active' to i386/i386/db_interface.d (as in
  alpha/alpha/db_interface.c).
- Remove cnpollc() stub from ddb/db_input.c.
- Add the dbctl function to syscons, pcvt, and sio. (The function for
  pcvt and sio is noop at the moment.)

Jointly developed by: bde and me

(The final version was tweaked by me and not reviewed by bde.  Thus,
if there is any error in this commit, that is entirely of mine, not
his.)

Some changes were obtained from: NetBSD
2000-01-11 14:54:01 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Poul-Henning Kamp
3000820ae0 add some amount of sanity to the way the gdb stuff finds its device.
I'm not too happy about the result either, but at least it has less
chance of backfiring.

This particular feature could be called "a mess" without offending
anybody.
1999-05-09 10:51:13 +00:00
Matthew Dillon
a1c1e16ada Changes to support -Wall, -Wcast-qual. Had to make physical code changes
in db_lookup() to avoid the *cp = 0 / *cp = ':' combo ( temporary
    nul-terminate-then-restore-original ) on a const char * string.
1999-01-27 19:00:49 +00:00
Bruce Evans
748993b899 Added macros __printflike() and __scanflike() to <sys/cdefs.h>.
Use them to `make gcc -Wformat' check formats for all printf-like
and scanf-like functions in /usr/src except for the err()/warn()
family.  err() isn't quite printf-like since its format arg can
legitimately be NULL.  syslog() isn't quite printf-like, but gcc
already accepts %m, even for plain printf() when it shouldn't.
1998-07-13 06:45:23 +00:00
Bruce Evans
3da6ef3c3a Fixed bogus type of valuep in struct db_variable. It was `int *' and
became `long *' for alpha, but should always have been `db_expr_t *'.
Fixed variable types to match.
1998-07-08 09:11:43 +00:00
Doug Rabson
ecbb00a262 This commit fixes various 64bit portability problems required for
FreeBSD/alpha.  The most significant item is to change the command
argument to ioctl functions from int to u_long.  This change brings us
inline with various other BSD versions.  Driver writers may like to
use (__FreeBSD_version == 300003) to detect this change.

The prototype FreeBSD/alpha machdep will follow in a couple of days
time.
1998-06-07 17:13:14 +00:00
Poul-Henning Kamp
aec5a849f9 Redo the previous commit in a more Bruce-friendly fashion.
Urged by:	bde
1998-05-19 18:42:09 +00:00
Poul-Henning Kamp
7ee17eea02 Add "show msgbuf" command 1998-05-19 11:02:24 +00:00
Bruce Evans
b7aa38c1e3 Ensure that the linker sets for commands exist by putting a standard
command in each of them.  This removes the need for hard-to-configure
dummy instantiations of the sets.
1998-02-13 02:19:29 +00:00
Peter Wemm
6875d25465 Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.
1997-02-22 09:48:43 +00:00
Jordan K. Hubbard
1130b656e5 Make the long-awaited change from $Id$ to $FreeBSD$
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore.  This update would have been
insane otherwise.
1997-01-14 07:20:47 +00:00
Bruce Evans
6337f4efa8 Support statically attaching of ddb commands in non-ddb modules.
The details are hidden in the DB_COMMAND(cmd_name, func_name) and
DB_SHOW_COMMAND(cmd_name, func_name) macros.  DB_COMMAND() adds to
the top-level ddb command table and DB_SHOW_COMMAND adds to the
`show' subtable.  Most external commands will probably be `show'
commands with no side effects.  They should check their pointer
args more carefully than `show map' :-), or ddb should trap internal
faults better (like it does for memory accesses).

The vm ddb commands are temporarily unattached.

ddb.h:
Also declare `db_indent' and db_iprintf() which will replace vm's
`indent' and iprintf().
1996-09-14 09:13:15 +00:00
Gary Palmer
6ddbf1e299 Clean up various compiler warnings. Most (if not all) were benign
Reviewed by:	bde
1996-05-08 04:29:08 +00:00
Poul-Henning Kamp
25eb640d90 Staticize and cleanup. 1995-12-10 13:32:43 +00:00
David Greenman
efeaf95a41 Untangled the vm.h include file spaghetti. 1995-12-07 12:48:31 +00:00
Poul-Henning Kamp
f73a856d23 Staticized and '#ifdef notused' stuff we don't use. 1995-11-29 10:25:50 +00:00
Bruce Evans
4753168fae Completed function declarations and/or added prototypes.
Removed `extern' from prototypes.
Sorted prototypes.
Uniformized idempotency ifdefs.
1995-11-24 13:53:05 +00:00
Rodney W. Grimes
9b2e535452 Remove trailing whitespace. 1995-05-30 08:16:23 +00:00
Bruce Evans
b5e8ce9f12 Add and move declarations to fix all of the warnings from `gcc -Wimplicit'
(except in netccitt, netiso and netns) and most of the warnings from
`gcc -Wnested-externs'.  Fix all the bugs found.  There were no serious
ones.
1995-03-16 18:17:34 +00:00
David Greenman
e00fb8aaea Woops, wrong solution to the problem. Backed out previous fix to ddb.h, and
nuked the db_printf() declaration from db_output.h.
Reviewed by:
Submitted by:
Obtained from:
1994-09-27 12:15:56 +00:00