This is the equivalent of commit 001bf455d2 ("ARM: 8428/1: kgdb: Fix
registers on sleeping tasks") but for arm64. Nuff said.
...well, perhaps I could also add that task_pt_regs are userspace
registers and that's not what kgdb is supposed to be reporting. We're
supposed to be reporting kernel registers.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/task_stack.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
ARM64 step exception does not have any syndrome information. So, it is
responsibility of exception handler to take care that they handle it
only if exception was raised for them.
Since kgdb_step_brk_fn() always returns 0, therefore we might have problem
when we will have other step handler registered as well.
This patch fixes kgdb_step_brk_fn() to return error in case of step handler
was not meant for kgdb.
Signed-off-by: Pratyush Anand <panand@redhat.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Handle read-only cases when CONFIG_DEBUG_RODATA (4.0) or
CONFIG_DEBUG_SET_MODULE_RONX (3.18) are enabled by using
aarch64_insn_write() instead of probe_kernel_write() as introduced by
commit 2f896d5866 ("arm64: use fixmap for text patching") in 4.0.
Fixes: 11d91a770f ("arm64: Add CONFIG_DEBUG_SET_MODULE_RONX support")
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add all function symbols which are called from do_debug_exception under
NOKPROBE_SYMBOL, as they can not kprobed.
Signed-off-by: Pratyush Anand <panand@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Current versions of gdb do not interoperate cleanly with kgdb on arm64
systems because gdb and kgdb do not use the same register description.
This patch modifies kgdb to work with recent releases of gdb (>= 7.8.1).
Compatibility with gdb (after the patch is applied) is as follows:
gdb-7.6 and earlier Ok
gdb-7.7 series Works if user provides custom target description
gdb-7.8(.0) Works if user provides custom target description
gdb-7.8.1 and later Ok
When commit 44679a4f14 ("arm64: KGDB: Add step debugging support") was
introduced it was paired with a gdb patch that made an incompatible
change to the gdbserver protocol. This patch was eventually merged into
the gdb sources:
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commit;h=a4d9ba85ec5597a6a556afe26b712e878374b9dd
The change to the protocol was mostly made to simplify big-endian support
inside the kernel gdb stub. Unfortunately the gdb project released
gdb-7.7.x and gdb-7.8.0 before the protocol incompatibility was identified
and reversed:
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commit;h=bdc144174bcb11e808b4e73089b850cf9620a7ee
This leaves us in a position where kgdb still uses the no-longer-used
protocol; gdb-7.8.1, which restored the original behaviour, was
released on 2014-10-29.
I don't believe it is possible to detect/correct the protocol
incompatiblity which means the kernel must take a view about which
version of the gdb remote protocol is "correct". This patch takes the
view that the original/current version of the protocol is correct
and that version found in gdb-7.7.x and gdb-7.8.0 is anomalous.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The way the KGDB_DYN_BRK_INS_BYTEx macros are declared is more
complex than it needs to be. Also, the macros are only used in one
place, which is arch-specific anyway.
This patch refactors the macros to simplify them, and exposes an
argument so that we can have a single macro instead of 4.
As a side effect, this patch also fixes some anomalous spellings of
"KGDB".
These changes alter the compile types of some integer constants
that are harmless but trigger truncation warnings in gcc when
assigning to 32-bit variables. This patch adds an explicit cast
for the affected cases.
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The naming of DBG_ESR_VAL_BRK is inconsistent with the way other
similar macros are named.
This patch makes the naming more consistent, and appends "64"
as a reminder that this ESR pattern only matches from AArch64
state.
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Some of the KGDB macros used for generating the BRK instructions had the
wrong spelling for DBG and KGDB abbreviations.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add KGDB software step debugging support for EL1 debug
in AArch64 mode.
KGDB registers step debug handler with debug monitor.
On receiving 'step' command from GDB tool, target enables
software step debugging and step address is updated in ELR.
Software Step debugging is disabled when 'continue' command
is received
Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add KGDB debug support for kernel debugging.
With this patch, basic KGDB debugging is possible.GDB register
layout is updated and GDB tool can establish connection with
target and can set/clear breakpoints.
Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Douglas Anderson