linux-toradex.git/include/linux/kgdb.h, branch v4.17-rc1

kgdb: Remove "weak" from kgdb_arch_pc() declaration

2014-10-22T22:14:04+00:00

kernel/debug/debug_core.c provides a default kgdb_arch_pc() definition
explicitly marked "weak".  Several architectures provide their own
definitions intended to override the default, but the "weak" attribute on
the declaration applied to the arch definitions as well, so the linker
chose one based on link order (see 10629d711ed7 ("PCI: Remove __weak
annotation from pcibios_get_phb_of_node decl")).

Remove the "weak" attribute from the declaration so we always prefer a
non-weak definition over the weak one, independent of link order.

Fixes: 688b744d8bc8 ("kgdb: fix signedness mixmatches, add statics, add declaration to header")
Tested-by: Vineet Gupta 	# for ARC build
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Harvey Harrison

kgdb/kdb: Fix no KDB config problem

2014-01-25T07:55:09+00:00

Some code added to the debug_core module had KDB dependencies
that it shouldn't have.  Move the KDB dependent REASON back to
the caller to remove the dependency in the debug core code.

Update the call from the UV NMI handler to conform to the new
interface.

Signed-off-by: Mike Travis 
Reviewed-by: Hedi Berriche 
Cc: Russ Anderson 
Cc: Jason Wessel 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
Cc: Arnaldo Carvalho de Melo 
Link: http://lkml.kernel.org/r/20140114162551.318251993@asylum.americas.sgi.com
Signed-off-by: Ingo Molnar

kdb: Add support for external NMI handler to call KGDB/KDB

2013-10-03T16:47:54+00:00

This patch adds a kgdb_nmicallin() interface that can be used by
external NMI handlers to call the KGDB/KDB handler.  The primary
need for this is for those types of NMI interrupts where all the
CPUs have already received the NMI signal.  Therefore no
send_IPI(NMI) is required, and in fact it will cause a 2nd
unhandled NMI to occur. This generates the "Dazed and Confuzed"
messages.

Since all the CPUs are getting the NMI at roughly the same time,
it's not guaranteed that the first CPU that hits the NMI handler
will manage to enter KGDB and set the dbg_master_lock before the
slaves start entering. The new argument "send_ready" was added
for KGDB to signal the NMI handler to release the slave CPUs for
entry into KGDB.

Signed-off-by: Mike Travis 
Acked-by: Jason Wessel 
Reviewed-by: Dimitri Sivanich 
Reviewed-by: Hedi Berriche 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
Cc: Arnaldo Carvalho de Melo 
Link: http://lkml.kernel.org/r/20131002151417.928886849@asylum.americas.sgi.com
Signed-off-by: Ingo Molnar

kgdb: remove #include from kgdb.h

2013-02-04T23:35:26+00:00

There's no reason kgdb.h itself needs to include the 8250 serial port
header file.  So push it down to the _very_ limited number of individual
drivers that need the values in that file, and fix up the places where
people really wanted serial_core.h and platform_device.h.

Signed-off-by: Greg Kroah-Hartman

tty/serial: Add kgdb_nmi driver

2012-09-26T20:52:36+00:00

This special driver makes it possible to temporary use NMI debugger port
as a normal console by issuing 'nmi_console' command (assuming that the
port is attached to KGDB).

Unlike KDB's disable_nmi command, with this driver you are always able
to go back to the debugger using KGDB escape sequence ($3#33).  This is
because this console driver processes the input in NMI context, and thus
is able to intercept the magic sequence.

Note that since the console interprets input and uses polling
communication methods, for things like PPP it is still better to fully
detach debugger port from the KGDB NMI (i.e. disable_nmi), and use raw
console.

Usually, to enter the debugger one have to type the magic sequence, so
initially the kernel will print the following prompt on the NMI debugger
console:

	Type $3#33 to enter the debugger>

For convenience, there is a kgdb_fiq.knock kernel command line option,
when set to 0, this turns the special command to just a return key
press, so the kernel will be printing this:

	Hit  to enter the debugger>

This is more convenient for long debugging sessions, although it makes
nmi_console feature somewhat useless.

And for the cases when NMI connected to a dedicated button, the knocking
can be disabled altogether by setting kgdb_fiq.knock to -1.

Suggested-by: Colin Cross 
Signed-off-by: Anton Vorontsov 
Acked-by: Alan Cox 
Acked-by: Jason Wessel 
Signed-off-by: Greg Kroah-Hartman

kernel/debug: Mask KGDB NMI upon entry

2012-09-26T20:42:25+00:00

The new arch callback should manage NMIs that usually cause KGDB to
enter. That is, not all NMIs should be enabled/disabled, but only
those that issue kgdb_handle_exception().

We must mask it as serial-line interrupt can be used as an NMI, so
if the original KGDB-entry cause was say a breakpoint, then every
input to KDB console will cause KGDB to reenter, which we don't want.

Signed-off-by: Anton Vorontsov 
Acked-by: Jason Wessel 
Signed-off-by: Greg Kroah-Hartman

x86,kgdb: Fix DEBUG_RODATA limitation using text_poke()

2012-03-29T22:41:25+00:00

There has long been a limitation using software breakpoints with a
kernel compiled with CONFIG_DEBUG_RODATA going back to 2.6.26. For
this particular patch, it will apply cleanly and has been tested all
the way back to 2.6.36.

The kprobes code uses the text_poke() function which accommodates
writing a breakpoint into a read-only page.  The x86 kgdb code can
solve the problem similarly by overriding the default breakpoint
set/remove routines and using text_poke() directly.

The x86 kgdb code will first attempt to use the traditional
probe_kernel_write(), and next try using a the text_poke() function.
The break point install method is tracked such that the correct break
point removal routine will get called later on.

Cc: x86@kernel.org
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: H. Peter Anvin 
Cc: stable@vger.kernel.org # >= 2.6.36
Inspried-by: Masami Hiramatsu 
Signed-off-by: Jason Wessel

kgdb,debug_core: pass the breakpoint struct instead of address and memory

2012-03-29T22:41:25+00:00

There is extra state information that needs to be exposed in the
kgdb_bpt structure for tracking how a breakpoint was installed.  The
debug_core only uses the the probe_kernel_write() to install
breakpoints, but this is not enough for all the archs.  Some arch such
as x86 need to use text_poke() in order to install a breakpoint into a
read only page.

Passing the kgdb_bpt structure to kgdb_arch_set_breakpoint() and
kgdb_arch_remove_breakpoint() allows other archs to set the type
variable which indicates how the breakpoint was installed.

Cc: stable@vger.kernel.org # >= 2.6.36
Signed-off-by: Jason Wessel

atomic: use

2011-07-26T23:49:47+00:00

This allows us to move duplicated code in 
(atomic_inc_not_zero() for now) to 

Signed-off-by: Arun Sharma 
Reviewed-by: Eric Dumazet 
Cc: Ingo Molnar 
Cc: David Miller 
Cc: Eric Dumazet 
Acked-by: Mike Frysinger 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

KGDB: Notify GDB of machine halt, reboot or power off

2011-03-18T16:54:31+00:00

Notify GDB of the machine halting, rebooting or powering off by sending it an
exited command (remote protocol command 'W').  This is done by calling:

	void gdbstub_exit(int status)

from the arch's machine_{halt,restart,power_off}() functions with an
appropriate exit status to be reported to GDB.

Signed-off-by: David Howells