Subject: Re: [PATCH v3 02/11] kselftest: arm64: adds first test and common utils

From: Cristian Marussi <[email-masked]>
Date: Tue, 27 Aug 2019 15:24:21 +0100

Hi

On 14/08/2019 11:22, Amit Kachhap wrote:
> Hi Cristian,
> 
> I have few more comments,
> 
> On 8/13/19 6:52 PM, Cristian Marussi wrote:
>> Hi Amit
>>
>> thanks for the review.
>>
>> On 12/08/2019 13:43, Amit Kachhap wrote:
>>> Hi Cristian,
>>>
>>> On 8/2/19 10:32 PM, Cristian Marussi wrote:
>>>> Added some arm64/signal specific boilerplate and utility code to help
>>>> further testcase development.
>>>>
>>>> A simple testcase and related helpers are also introduced in this commit:
>>>> mangle_pstate_invalid_compat_toggle is a simple mangle testcase which
>>>> messes with the ucontext_t from within the sig_handler, trying to toggle
>>>> PSTATE state bits to switch the system between 32bit/64bit execution state.
>>>> Expects SIGSEGV on test PASS.
>>>>
>>>> Signed-off-by: Cristian Marussi <[email-masked]>
>>>> ---
>>>> A few fixes:
>>>> - test_arm64_signals.sh runner script generation has been reviewed in order to
>>>>     be safe against the .gitignore
>>>> - using kselftest.h officially provided defines for tests' return values
>>>> - removed SAFE_WRITE()/dump_uc()
>>>> - looking for si_code==SEGV_ACCERR on SEGV test cases to better understand if
>>>>     the sigfault had been directly triggered by Kernel
>>>> ---
>>>>    tools/testing/selftests/arm64/Makefile        |   2 +-
>>>>    .../testing/selftests/arm64/signal/.gitignore |   6 +
>>>>    tools/testing/selftests/arm64/signal/Makefile |  88 ++++++
>>>>    tools/testing/selftests/arm64/signal/README   |  59 ++++
>>>>    .../arm64/signal/test_arm64_signals.src_shell |  55 ++++
>>>>    .../selftests/arm64/signal/test_signals.c     |  26 ++
>>>>    .../selftests/arm64/signal/test_signals.h     | 137 +++++++++
>>>>    .../arm64/signal/test_signals_utils.c         | 261 ++++++++++++++++++
>>>>    .../arm64/signal/test_signals_utils.h         |  13 +
>>>>    .../arm64/signal/testcases/.gitignore         |   1 +
>>>>    .../mangle_pstate_invalid_compat_toggle.c     |  25 ++
>>>>    .../arm64/signal/testcases/testcases.c        | 150 ++++++++++
>>>>    .../arm64/signal/testcases/testcases.h        |  83 ++++++
>>>>    13 files changed, 905 insertions(+), 1 deletion(-)
>>>>    create mode 100644 tools/testing/selftests/arm64/signal/.gitignore
>>>>    create mode 100644 tools/testing/selftests/arm64/signal/Makefile
>>>>    create mode 100644 tools/testing/selftests/arm64/signal/README
>>>>    create mode 100755 tools/testing/selftests/arm64/signal/test_arm64_signals.src_shell
>>>>    create mode 100644 tools/testing/selftests/arm64/signal/test_signals.c
>>>>    create mode 100644 tools/testing/selftests/arm64/signal/test_signals.h
>>>>    create mode 100644 tools/testing/selftests/arm64/signal/test_signals_utils.c
>>>>    create mode 100644 tools/testing/selftests/arm64/signal/test_signals_utils.h
>>>>    create mode 100644 tools/testing/selftests/arm64/signal/testcases/.gitignore
>>>>    create mode 100644 tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_compat_toggle.c
>>>>    create mode 100644 tools/testing/selftests/arm64/signal/testcases/testcases.c
>>>>    create mode 100644 tools/testing/selftests/arm64/signal/testcases/testcases.h
>>>>
>>>> diff --git a/tools/testing/selftests/arm64/Makefile b/tools/testing/selftests/arm64/Makefile
>>>> index 03a0d4f71218..af59dc74e0dc 100644
>>>> --- a/tools/testing/selftests/arm64/Makefile
>>>> +++ b/tools/testing/selftests/arm64/Makefile
>>>> @@ -6,7 +6,7 @@ ARCH ?= $(shell uname -m)
>>>>    ARCH := $(shell echo $(ARCH) | sed -e s/aarch64/arm64/)
>>>>    
>>>>    ifeq ("x$(ARCH)", "xarm64")
>>>> -SUBDIRS :=
>>>> +SUBDIRS := signal
>>>>    else
>>>>    SUBDIRS :=
>>>>    endif
>>>> diff --git a/tools/testing/selftests/arm64/signal/.gitignore b/tools/testing/selftests/arm64/signal/.gitignore
>>>> new file mode 100644
>>>> index 000000000000..434f65c15f03
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/arm64/signal/.gitignore
>>>> @@ -0,0 +1,6 @@
>>>> +# Helper script's internal testcases list (TPROGS) is regenerated
>>>> +# each time by Makefile on standalone (non KSFT driven) runs.
>>>> +# Committing such list creates a dependency between testcases
>>>> +# patches such that they are no more easily revertable. Just ignore.
>>>> +test_arm64_signals.src_shell
>>>> +test_arm64_signals.sh
>>>> diff --git a/tools/testing/selftests/arm64/signal/Makefile b/tools/testing/selftests/arm64/signal/Makefile
>>>> new file mode 100644
>>>> index 000000000000..8c8d08be4b0d
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/arm64/signal/Makefile
>>>> @@ -0,0 +1,88 @@
>>>> +# SPDX-License-Identifier: GPL-2.0
>>>> +# Copyright (C) 2019 ARM Limited
>>>> +
>>>> +# Supports also standalone invokation out of KSFT-tree
>>>> +# Compile standalone and run on your device with:
>>>> +#
>>>> +#  $ make -C tools/testing/selftests/arm64/signal INSTALL_PATH=<your-dir> install
>>>> +#
>>>> +# Run standalone on device with:
>>>> +#
>>>> +#  $ <your-device-instdir>/test_arm64_signals.sh [-k|-v]
>>>> +#
>>>> +# If INSTALL_PATH= is NOT provided it will default to ./install
>>>> +
>>>> +# A proper top_srcdir is needed both by KSFT(lib.mk)
>>>> +# and standalone builds
>>>> +top_srcdir = ../../../../..
>>>> +
>>>> +CFLAGS += -std=gnu99 -I. -I$(top_srcdir)/tools/testing/selftests/
>>>> +SRCS := $(filter-out testcases/testcases.c,$(wildcard testcases/*.c))
>>>> +PROGS := $(patsubst %.c,%,$(SRCS))
>>>> +
>>>> +# Guessing as best as we can where the Kernel headers
>>>> +# could have been installed depending on ENV config and
>>>> +# type of invocation.
>>>> +ifeq ($(KBUILD_OUTPUT),)
>>>> +khdr_dir = $(top_srcdir)/usr/include
>>>> +else
>>>> +ifeq (0,$(MAKELEVEL))
>>>> +khdr_dir = $(KBUILD_OUTPUT)/usr/include
>>>> +else
>>>> +# the KSFT preferred location when KBUILD_OUTPUT is set
>>>> +khdr_dir = $(KBUILD_OUTPUT)/kselftest/usr/include
>>>> +endif
>>>> +endif
>>>> +
>>>> +CFLAGS += -I$(khdr_dir)
>>>> +
>>>> +# Standalone run
>>>> +ifeq (0,$(MAKELEVEL))
>>>> +CC := $(CROSS_COMPILE)gcc
>>>> +RUNNER_SRC = test_arm64_signals.src_shell
>>>> +RUNNER = test_arm64_signals.sh
> Is this extra level of copying test_arm64_signals.src_shell to 
> test_arm64_signals.sh required? I cannot see them in other selftests.
> Also if done then clean may be required. May be EXTRA_CLEAN parameter
> can be used as done for other selftests.
This was the runner script for standalone mode (build/run): it was generated on
the fly sedding the PROGS list inside the .src_shell template script: I had to be
done this way in order to properly have it .gitignored
Anyway I'm throwing away standalone mode in V4

>>>> +INSTALL_PATH ?= install/
> Here default INSTALL_PATH should be just "install" as it may insert "/" 
> twice for below install case.

Ok
>>>> +
>>>> +all: $(RUNNER)
>>>> +
>>>> +$(RUNNER): $(PROGS)
>>>> +	cp $(RUNNER_SRC) $(RUNNER)
>>>> +	sed -i -e 's#PROGS=.*#PROGS="$(PROGS)"#' $@
>>>> +
>>>> +install: all
>>>> +	mkdir -p $(INSTALL_PATH)/testcases
>>>> +	cp $(PROGS) $(INSTALL_PATH)/testcases
>>>> +	cp $(RUNNER) $(INSTALL_PATH)/
>>>> +
>>>> +.PHONY clean:
>>>> +	rm -f $(PROGS)
>>>> +# KSFT run
>>>> +else
>>>> +# Generated binaries to be installed by top KSFT script
>>>> +TEST_GEN_PROGS := $(notdir $(PROGS))
>>>> +
>>>> +# Get Kernel headers installed and use them.
>>>> +KSFT_KHDR_INSTALL := 1
>>>> +
>>>> +# This include mk will also mangle the TEST_GEN_PROGS list
>>>> +# to account for any OUTPUT target-dirs optionally provided
>>>> +# by the toplevel makefile
>>>> +include ../../lib.mk
>>>> +
>>>> +$(TEST_GEN_PROGS): $(PROGS)
>>>> +	cp $(PROGS) $(OUTPUT)/
> I guess this copy requires cleaning too.
I'll double check but I think OUTPUT is already cleaned by lib.mk default $(CLEAN) target
called below....here I'm copying the just built PROGS in their final destination OUTPUT
since they were built in the subdir arm64/signal and it could not be found by KSFT otherwise,
which expects they in OUTPUT.

>>>> +
>>>> +clean:
>>>> +	$(CLEAN)
>>>> +	rm -f $(PROGS)
> Is clean requires to clean installed programs also?

I avoided cleaning explicitly installed programs. I think by convention Make target
clean is not expected to remove installed files.
ftp://ftp.gnu.org/old-gnu/Manuals/make-3.79.1/html_chapter/make_14.html

uninstall seems a possible target for that operation, but KSFT does not define it.

Anyway given that these tests could be installed on NFS share mounted on remote testing unit
I don't think it is useful here to be able to unistall

Thanks

Cristian

>>>> +endif
>>>> +
>>>> +# Common test-unit targets to build common-layout test-cases executables
>>>> +# Needs secondary expansion to properly include the testcase c-file in pre-reqs
>>>> +.SECONDEXPANSION:
>>>> +$(PROGS): test_signals.c test_signals_utils.c testcases/testcases.c $$@.c test_signals.h test_signals_utils.h testcases/testcases.h
>>>
>>> I suppose *.h can be removed from the targets here.
>>
>> *.h are in the pre-reqs, $(PROGS) represent the targets and it's comprised by the *.c file contained in testcases/ (excluding testcases.c)
>>
>> If I remove the *.h from this rule, targets won't be rebuilt when headers are changed (like after having added an hypotethical inline)...
>>
>> or am I missing something else ?
> Yes You are right.
> 
> Thanks,
> Amit Daniel
>>
>>
>>>
>>>
>>>> +	@if [ ! -d $(khdr_dir) ]; then \
>>>> +		echo -n "\n!!! WARNING: $(khdr_dir) NOT FOUND."; \
>>>> +		echo "===>  Are you sure Kernel Headers have been installed properly ?\n"; \
>>>> +	fi
>>>> +	$(CC) $(CFLAGS) $^ -o $@
>>>> diff --git a/tools/testing/selftests/arm64/signal/README b/tools/testing/selftests/arm64/signal/README
>>>> new file mode 100644
>>>> index 000000000000..53f005f7910a
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/arm64/signal/README
>>>> @@ -0,0 +1,59 @@
>>>> +KSelfTest arm64/signal/
>>>> +=======================
>>>> +
>>>> +Signals Tests
>>>> ++++++++++++++
>>>> +
>>>> +- Tests are built around a common main compilation unit: such shared main
>>>> +  enforces a standard sequence of operations needed to perform a single
>>>> +  signal-test (setup/trigger/run/result/cleanup)
>>>> +
>>>> +- The above mentioned ops are configurable on a test-by-test basis: each test
>>>> +  is described (and configured) using the descriptor signals.h::struct tdescr
>>>> +
>>>> +- Each signal testcase is compiled into its own executable: a separate
>>>> +  executable is used for each test since many tests complete successfully
>>>> +  by receiving some kind of fatal signal from the Kernel, so it's safer
>>>> +  to run each test unit in its own standalone process, so as to start each
>>>> +  test from a clean slate.
>>>> +
>>>> +- New tests can be simply defined in testcases/ dir providing a proper struct
>>>> +  tdescr overriding all the defaults we wish to change (as of now providing a
>>>> +  custom run method is mandatory though)
>>>> +
>>>> +- Signals' test-cases hereafter defined belong currently to two
>>>> +  principal families:
>>>> +
>>>> +  - 'mangle_' tests: a real signal (SIGUSR1) is raised and used as a trigger
>>>> +    and then the test case code messes-up with the sigframe ucontext_t from
>>>> +    inside the sighandler itself.
>>>> +
>>>> +  - 'fake_sigreturn_' tests: a brand new custom artificial sigframe structure
>>>> +    is placed on the stack and a sigreturn syscall is called to simulate a
>>>> +    real signal return. This kind of tests does not use a trigger usually and
>>>> +    they are just fired using some simple included assembly trampoline code.
>>>> +
>>>> + - Most of these tests are successfully passing if the process gets killed by
>>>> +   some fatal signal: usually SIGSEGV or SIGBUS. Since while writing this
>>>> +   kind of tests it is extremely easy in fact to end-up injecting other
>>>> +   unrelated SEGV bugs in the testcases, it becomes extremely tricky to
>>>> +   be really sure that the tests are really addressing what they are meant
>>>> +   to address and they are not instead falling apart due to unplanned bugs
>>>> +   in the test code.
>>>> +   In order to alleviate the misery of the life of such test-developer, a few
>>>> +   helpers are provided:
>>>> +
>>>> +   - a couple of ASSERT_BAD/GOOD_CONTEXT() macros to easily parse a ucontext_t
>>>> +     and verify if it is indeed GOOD or BAD (depending on what we were
>>>> +     expecting), using the same logic/perspective as in the arm64 Kernel signals
>>>> +     routines.
>>>> +
>>>> +   - a sanity mechanism to be used in 'fake_sigreturn_'-alike tests: enabled by
>>>> +     default it takes care to verify that the test-execution had at least
>>>> +     successfully progressed up to the stage of triggering the fake sigreturn
>>>> +     call.
>>>> +
>>>> +  In both cases test results are expected in terms of:
>>>> +   - some fatal signal sent by the Kernel to the test process
>>>> +  or
>>>> +  - analyzing some final regs state
>>>> diff --git a/tools/testing/selftests/arm64/signal/test_arm64_signals.src_shell b/tools/testing/selftests/arm64/signal/test_arm64_signals.src_shell
>>>> new file mode 100755
>>>> index 000000000000..163e941e2997
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/arm64/signal/test_arm64_signals.src_shell
>>>> @@ -0,0 +1,55 @@
>>>> +#!/bin/sh
>>>> +# SPDX-License-Identifier: GPL-2.0
>>>> +# Copyright (C) 2019 ARM Limited
>>>> +
>>>> +ret=0
>>>> +keep_on_fail=0
>>>> +err_out="2> /dev/null"
>>>> +
>>>> +usage() {
>>>> +	echo "Usage: `basename $0` [-v] [-k]"
>>>> +	exit 1
>>>> +}
>>>> +
>>>> +# avoiding getopt to avoid compatibility issues on targets
>>>> +# with limited resources
>>>> +while [ $# -gt 0 ]
>>>> +do
>>>> +	case $1 in
>>>> +		"-k")
>>>> +			keep_on_fail=1
>>>> +			;;
>>>> +		"-v")
>>>> +			err_out=
>>>> +			;;
>>>> +		*)
>>>> +			usage
>>>> +			;;
>>>> +	esac
>>>> +	shift
>>>> +done
>>>> +
>>>> +TPROGS=
>>>> +
>>>> +tot=$(echo $TPROGS | wc -w)
>>>> +
>>>> +# Tests are expected in testcases/ subdir inside the installation path
>>>> +workdir="`dirname $0 2>/dev/null`"
>>>> +[ -n $workdir ] && cd $workdir
>>>> +
>>>> +passed=0
>>>> +run=0
>>>> +for test in $TPROGS
>>>> +do
>>>> +	run=$((run + 1))
>>>> +	eval ./$test $err_out
>>>> +	if [ $? != 0 ]; then
>>>> +		[ $keep_on_fail = 0 ] && echo "===>>> FAILED:: $test <<<===" && ret=1 && break
>>>> +	else
>>>> +		passed=$((passed + 1))
>>>> +	fi
>>>> +done
>>>> +
>>>> +echo "==>> PASSED: $passed/$run on $tot available tests."
>>>> +
>>>> +exit $ret
>>>> diff --git a/tools/testing/selftests/arm64/signal/test_signals.c b/tools/testing/selftests/arm64/signal/test_signals.c
>>>> new file mode 100644
>>>> index 000000000000..3447d7011aec
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/arm64/signal/test_signals.c
>>>> @@ -0,0 +1,26 @@
>>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>>> +/* Copyright (C) 2019 ARM Limited */
>>>> +
>>>> +#include <kselftest.h>
>>>> +
>>>> +#include "test_signals.h"
>>>> +#include "test_signals_utils.h"
>>>> +
>>>> +struct tdescr *current;
>>>> +extern struct tdescr tde;
>>>> +
>>>> +int main(int argc, char *argv[])
>>>> +{
>>>> +	current = &tde;
>>>> +
>>>> +	ksft_print_msg("%s :: %s - SIG_TRIG:%d  SIG_OK:%d -- current:%p\n",
>>>> +		       current->name, current->descr, current->sig_trig,
>>>> +		       current->sig_ok, current);
>>>> +	if (test_setup(current)) {
>>>> +		if (test_run(current))
>>>> +			test_result(current);
>>>> +		test_cleanup(current);
>>>> +	}
>>>> +
>>>> +	return current->pass ? KSFT_PASS : KSFT_FAIL;
>>>> +}
>>>> diff --git a/tools/testing/selftests/arm64/signal/test_signals.h b/tools/testing/selftests/arm64/signal/test_signals.h
>>>> new file mode 100644
>>>> index 000000000000..85db3ac44b32
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/arm64/signal/test_signals.h
>>>> @@ -0,0 +1,137 @@
>>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>>> +/* Copyright (C) 2019 ARM Limited */
>>>> +
>>>> +#ifndef __TEST_SIGNALS_H__
>>>> +#define __TEST_SIGNALS_H__
>>>> +
>>>> +#include <assert.h>
>>>> +#include <stdbool.h>
>>>> +#include <signal.h>
>>>> +#include <ucontext.h>
>>>> +#include <stdint.h>
>>> Headers can be added in alphabetically order.
>>>
>> Ok I'll do.
>>
>> Cheers
>>
>> Cristian
>>
>>> Thanks,
>>> Amit D
>>>> +
>>>> +/*
>>>> + * Using ARCH specific and sanitized Kernel headers installed by KSFT
>>>> + * framework since we asked for it by setting flag KSFT_KHDR_INSTALL
>>>> + * in our Makefile.
>>>> + */
>>>> +#include <asm/ptrace.h>
>>>> +#include <asm/hwcap.h>
>>>> +
>>>> +/* pasted from include/linux/stringify.h */
>>>> +#define __stringify_1(x...)	#x
>>>> +#define __stringify(x...)	__stringify_1(x)
>>>> +
>>>> +/*
>>>> + * Reads a sysreg using the, possibly provided, S3_ encoding in order to
>>>> + * avoid inject any dependency on the used toolchain regarding possibly
>>>> + * still unsupported ARMv8 extensions.
>>>> + *
>>>> + * Using a standard mnemonic here to indicate the specific sysreg (like SSBS)
>>>> + * would introduce a compile-time dependency on possibly unsupported ARMv8
>>>> + * Extensions: you could end-up failing to build the test depending on the
>>>> + * available toolchain.
>>>> + * This is undesirable since some tests, even if specifically targeted at some
>>>> + * ARMv8 Extensions, can be plausibly run even on hardware lacking the above
>>>> + * optional ARM features. (SSBS bit preservation is an example: Kernel handles
>>>> + * it transparently not caring at all about the effective set of supported
>>>> + * features).
>>>> + * On the other side we will expect to observe different behaviours if the
>>>> + * feature is supported or not: usually getting a SIGILL when trying to use
>>>> + * unsupported features. For this reason we have anyway in place some
>>>> + * preliminary run-time checks about the cpu effectively supported features.
>>>> + *
>>>> + * This helper macro is meant to be used for regs readable at EL0, BUT some
>>>> + * EL1 sysregs are indeed readable too through MRS emulation Kernel-mechanism
>>>> + * if the required reg is included in the supported encoding space:
>>>> + *
>>>> + *  Documentation/arm64/cpu-feature-regsiters.txt
>>>> + *
>>>> + *  "The infrastructure emulates only the following system register space:
>>>> + *   	Op0=3, Op1=0, CRn=0, CRm=0,4,5,6,7
>>>> + */
>>>> +#define get_regval(regname, out) \
>>>> +	asm volatile("mrs %0, " __stringify(regname) : "=r" (out) :: "memory")
>>>> +
>>>> +/* Regs encoding and masks naming copied in from sysreg.h */
>>>> +#define SYS_ID_AA64MMFR1_EL1	S3_0_C0_C7_1	/* MRS Emulated */
>>>> +#define SYS_ID_AA64MMFR2_EL1	S3_0_C0_C7_2	/* MRS Emulated */
>>>> +#define ID_AA64MMFR1_PAN_SHIFT	20
>>>> +#define ID_AA64MMFR2_UAO_SHIFT	4
>>>> +
>>>> +/* Local Helpers */
>>>> +#define IS_PAN_SUPPORTED(val) \
>>>> +	(!!((val) & (0xfUL << ID_AA64MMFR1_PAN_SHIFT)))
>>>> +#define IS_UAO_SUPPORTED(val) \
>>>> +	(!!((val) & (0xfUL << ID_AA64MMFR2_UAO_SHIFT)))
>>>> +
>>>> +#define S3_MRS_SSBS_SYSREG		S3_3_C4_C2_6	/* EL0 supported */
>>>> +
>>>> +/*
>>>> + * Feature flags used in tdescr.feats_required to specify
>>>> + * any feature by the test
>>>> + */
>>>> +enum {
>>>> +	FSSBS_BIT,
>>>> +	FPAN_BIT,
>>>> +	FUAO_BIT,
>>>> +	FMAX_END
>>>> +};
>>>> +
>>>> +#define FEAT_SSBS		(1UL << FSSBS_BIT)
>>>> +#define FEAT_PAN		(1UL << FPAN_BIT)
>>>> +#define FEAT_UAO		(1UL << FUAO_BIT)
>>>> +
>>>> +/*
>>>> + * A descriptor used to describe and configure a test case.
>>>> + * Fields with a non-trivial meaning are described inline in the following.
>>>> + */
>>>> +struct tdescr {
>>>> +	/* KEEP THIS FIELD FIRST for easier lookup from assembly */
>>>> +	void		*token;
>>>> +	/* when disabled token based sanity checking is skipped in handler */
>>>> +	bool		sanity_disabled;
>>>> +	/* just a name for the test-case; manadatory field */
>>>> +	char		*name;
>>>> +	char		*descr;
>>>> +	unsigned long	feats_required;
>>>> +	/* bitmask of effectively supported feats: populated at run-time */
>>>> +	unsigned long	feats_supported;
>>>> +	bool		feats_ok;
>>>> +	bool		initialized;
>>>> +	unsigned int	minsigstksz;
>>>> +	/* signum used as a test trigger. Zero if no trigger-signal is used */
>>>> +	int		sig_trig;
>>>> +	/*
>>>> +	 * signum considered as a successful test completion.
>>>> +	 * Zero when no signal is expected on success
>>>> +	 */
>>>> +	int		sig_ok;
>>>> +	/* signum expected on unsupported CPU features. */
>>>> +	int		sig_unsupp;
>>>> +	/* a timeout in second for test completion */
>>>> +	unsigned int	timeout;
>>>> +	bool		triggered;
>>>> +	bool		pass;
>>>> +	/* optional sa_flags for the installed handler */
>>>> +	int		sa_flags;
>>>> +	ucontext_t	saved_uc;
>>>> +
>>>> +	/* a setup function to be called before test starts */
>>>> +	int (*setup)(struct tdescr *td);
>>>> +	void (*cleanup)(struct tdescr *td);
>>>> +
>>>> +	/* an optional function to be used as a trigger for test starting */
>>>> +	int (*trigger)(struct tdescr *td);
>>>> +	/*
>>>> +	 * the actual test-core: invoked differently depending on the
>>>> +	 * presence of the trigger function above; this is mandatory
>>>> +	 */
>>>> +	int (*run)(struct tdescr *td, siginfo_t *si, ucontext_t *uc);
>>>> +
>>>> +	/* an optional function for custom results' processing */
>>>> +	void (*check_result)(struct tdescr *td);
>>>> +
>>>> +	void *priv;
>>>> +};
>>>> +#endif
>>>> diff --git a/tools/testing/selftests/arm64/signal/test_signals_utils.c b/tools/testing/selftests/arm64/signal/test_signals_utils.c
>>>> new file mode 100644
>>>> index 000000000000..ac0055f6340b
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/arm64/signal/test_signals_utils.c
>>>> @@ -0,0 +1,261 @@
>>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>>> +/* Copyright (C) 2019 ARM Limited */
>>>> +
>>>> +#include <stdio.h>
>>>> +#include <stdlib.h>
>>>> +#include <signal.h>
>>>> +#include <string.h>
>>>> +#include <unistd.h>
>>>> +#include <assert.h>
>>>> +#include <sys/auxv.h>
>>>> +#include <linux/auxvec.h>
>>>> +#include <ucontext.h>
>>>> +
>>>> +#include "test_signals.h"
>>>> +#include "test_signals_utils.h"
>>>> +#include "testcases/testcases.h"
>>>> +
>>>> +extern struct tdescr *current;
>>>> +
>>>> +static char *feats_store[FMAX_END] = {
>>>> +	"SSBS",
>>>> +	"PAN",
>>>> +	"UAO"
>>>> +};
>>>> +
>>>> +#define MAX_FEATS_SZ	128
>>>> +static inline char *feats_to_string(unsigned long feats)
>>>> +{
>>>> +	static char feats_string[MAX_FEATS_SZ];
>>>> +
>>>> +	for (int i = 0; i < FMAX_END && feats_store[i][0]; i++) {
>>>> +		if (feats & 1UL << i)
>>>> +			snprintf(feats_string, MAX_FEATS_SZ - 1, "%s %s ",
>>>> +				 feats_string, feats_store[i]);
>>>> +	}
>>>> +
>>>> +	return feats_string;
>>>> +}
>>>> +
>>>> +static void unblock_signal(int signum)
>>>> +{
>>>> +	sigset_t sset;
>>>> +
>>>> +	sigemptyset(&sset);
>>>> +	sigaddset(&sset, signum);
>>>> +	sigprocmask(SIG_UNBLOCK, &sset, NULL);
>>>> +}
>>>> +
>>>> +static void default_result(struct tdescr *td, bool force_exit)
>>>> +{
>>>> +	if (td->pass)
>>>> +		fprintf(stderr, "==>> completed. PASS(1)\n");
>>>> +	else
>>>> +		fprintf(stdout, "==>> completed. FAIL(0)\n");
>>>> +	if (force_exit)
>>>> +		exit(td->pass ? EXIT_SUCCESS : EXIT_FAILURE);
>>>> +}
>>>> +
>>>> +static inline bool are_feats_ok(struct tdescr *td)
>>>> +{
>>>> +	return td ? td->feats_required == td->feats_supported : 0;
>>>> +}
>>>> +
>>>> +static void default_handler(int signum, siginfo_t *si, void *uc)
>>>> +{
>>>> +	if (current->sig_trig && signum == current->sig_trig) {
>>>> +		fprintf(stderr, "Handling SIG_TRIG\n");
>>>> +		current->triggered = 1;
>>>> +		/* ->run was asserted NON-NULL in test_setup() already */
>>>> +		current->run(current, si, uc);
>>>> +	} else if (signum == SIGILL && !current->initialized) {
>>>> +		/*
>>>> +		 * A SIGILL here while still not initialized means we failed
>>>> +		 * even to asses the existence of features during init
>>>> +		 */
>>>> +		fprintf(stdout,
>>>> +			"Got SIGILL test_init. Marking ALL features UNSUPPORTED.\n");
>>>> +		current->feats_supported = 0;
>>>> +	} else if (current->sig_ok && signum == current->sig_ok) {
>>>> +		/* it's a bug in the test code when this assert fail */
>>>> +		assert(!current->sig_trig || current->triggered);
>>>> +		fprintf(stderr,
>>>> +			"SIG_OK -- SP:%p  si_addr@:0x%p  si_code:%d  token@:0x%p  offset:%ld\n",
>>>> +			((ucontext_t *)uc)->uc_mcontext.sp,
>>>> +			si->si_addr, si->si_code, current->token,
>>>> +			current->token - si->si_addr);
>>>> +		/*
>>>> +		 * fake_sigreturn tests, which have sanity_enabled=1, set, at
>>>> +		 * the very last time, the token field to the SP address used
>>>> +		 * to place the fake sigframe: so token==0 means we never made
>>>> +		 * it to the end, segfaulting well-before, and the test is
>>>> +		 * possibly broken.
>>>> +		 */
>>>> +		if (!current->sanity_disabled && !current->token) {
>>>> +			fprintf(stdout,
>>>> +				"current->token ZEROED...test is probably broken!\n");
>>>> +			assert(0);
>>>> +		}
>>>> +		/*
>>>> +		 * Trying to narrow down the SEGV to the ones generated by
>>>> +		 * Kernel itself via arm64_notify_segfault()
>>>> +		 */
>>>> +		if (current->sig_ok == SIGSEGV && si->si_code != SEGV_ACCERR) {
>>>> +			fprintf(stdout,
>>>> +				"si_code != SEGV_ACCERR...test is probably broken!\n");
>>>> +			assert(0);
>>>> +		}
>>>> +		fprintf(stderr, "Handling SIG_OK\n");
>>>> +		current->pass = 1;
>>>> +		/*
>>>> +		 * Some tests can lead to SEGV loops: in such a case we want
>>>> +		 * to terminate immediately exiting straight away
>>>> +		 */
>>>> +		default_result(current, 1);
>>>> +	} else {
>>>> +		if (signum == current->sig_unsupp && !are_feats_ok(current)) {
>>>> +			fprintf(stderr, "-- RX SIG_UNSUPP on unsupported feature...OK\n");
>>>> +			current->pass = 1;
>>>> +		} else if (signum == SIGALRM && current->timeout) {
>>>> +			fprintf(stderr, "-- Timeout !\n");
>>>> +		} else {
>>>> +			fprintf(stderr,
>>>> +				"-- RX UNEXPECTED SIGNAL: %d\n", signum);
>>>> +		}
>>>> +		default_result(current, 1);
>>>> +	}
>>>> +}
>>>> +
>>>> +static int default_setup(struct tdescr *td)
>>>> +{
>>>> +	struct sigaction sa;
>>>> +
>>>> +	sa.sa_sigaction = default_handler;
>>>> +	sa.sa_flags = SA_SIGINFO;
>>>> +	if (td->sa_flags)
>>>> +		sa.sa_flags |= td->sa_flags;
>>>> +	sigemptyset(&sa.sa_mask);
>>>> +	/* uncatchable signals naturally skipped ... */
>>>> +	for (int sig = 1; sig < 32; sig++)
>>>> +		sigaction(sig, &sa, NULL);
>>>> +	/*
>>>> +	 * RT Signals default disposition is Term but they cannot be
>>>> +	 * generated by the Kernel in response to our tests; so just catch
>>>> +	 * them all and report them as UNEXPECTED signals.
>>>> +	 */
>>>> +	for (int sig = SIGRTMIN; sig <= SIGRTMAX; sig++)
>>>> +		sigaction(sig, &sa, NULL);
>>>> +
>>>> +	/* just in case...unblock explicitly all we need */
>>>> +	if (td->sig_trig)
>>>> +		unblock_signal(td->sig_trig);
>>>> +	if (td->sig_ok)
>>>> +		unblock_signal(td->sig_ok);
>>>> +	if (td->sig_unsupp)
>>>> +		unblock_signal(td->sig_unsupp);
>>>> +
>>>> +	if (td->timeout) {
>>>> +		unblock_signal(SIGALRM);
>>>> +		alarm(td->timeout);
>>>> +	}
>>>> +	fprintf(stderr, "Registered handlers for all signals.\n");
>>>> +
>>>> +	return 1;
>>>> +}
>>>> +
>>>> +static inline int default_trigger(struct tdescr *td)
>>>> +{
>>>> +	return !raise(td->sig_trig);
>>>> +}
>>>> +
>>>> +static int test_init(struct tdescr *td)
>>>> +{
>>>> +	td->minsigstksz = getauxval(AT_MINSIGSTKSZ);
>>>> +	if (!td->minsigstksz)
>>>> +		td->minsigstksz = MINSIGSTKSZ;
>>>> +	fprintf(stderr, "Detected MINSTKSIGSZ:%d\n", td->minsigstksz);
>>>> +
>>>> +	if (td->feats_required) {
>>>> +		bool feats_ok = false;
>>>> +		td->feats_supported = 0;
>>>> +		/*
>>>> +		 * Checking for CPU required features using both the
>>>> +		 * auxval and the arm64 MRS Emulation to read sysregs.
>>>> +		 */
>>>> +		if (getauxval(AT_HWCAP) & HWCAP_CPUID) {
>>>> +			uint64_t val = 0;
>>>> +
>>>> +			if (td->feats_required & FEAT_SSBS) {
>>>> +				/* Uses HWCAP to check capability */
>>>> +				if (getauxval(AT_HWCAP) & HWCAP_SSBS)
>>>> +					td->feats_supported |= FEAT_SSBS;
>>>> +			}
>>>> +			if (td->feats_required & FEAT_PAN) {
>>>> +				/* Uses MRS emulation to check capability */
>>>> +				get_regval(SYS_ID_AA64MMFR1_EL1, val);
>>>> +				if (IS_PAN_SUPPORTED(val))
>>>> +					td->feats_supported |= FEAT_PAN;
>>>> +			}
>>>> +			if (td->feats_required & FEAT_UAO) {
>>>> +				/* Uses MRS emulation to check capability */
>>>> +				get_regval(SYS_ID_AA64MMFR2_EL1 , val);
>>>> +				if (IS_UAO_SUPPORTED(val))
>>>> +					td->feats_supported |= FEAT_UAO;
>>>> +			}
>>>> +		} else {
>>>> +			fprintf(stderr,
>>>> +				"HWCAP_CPUID NOT available. Mark ALL feats UNSUPPORTED.\n");
>>>> +		}
>>>> +		feats_ok = are_feats_ok(td);
>>>> +		fprintf(stderr,
>>>> +			"Required Features: [%s] %ssupported\n",
>>>> +			feats_ok ? feats_to_string(td->feats_supported) :
>>>> +		        feats_to_string(td->feats_required ^ td->feats_supported),
>>>> +			!feats_ok ? "NOT " : "");
>>>> +	}
>>>> +
>>>> +	td->initialized = 1;
>>>> +	return 1;
>>>> +}
>>>> +
>>>> +int test_setup(struct tdescr *td)
>>>> +{
>>>> +	/* assert core invariants symptom of a rotten testcase */
>>>> +	assert(current);
>>>> +	assert(td);
>>>> +	assert(td->name);
>>>> +	assert(td->run);
>>>> +
>>>> +	if (!test_init(td))
>>>> +		return 0;
>>>> +
>>>> +	if (td->setup)
>>>> +		return td->setup(td);
>>>> +	else
>>>> +		return default_setup(td);
>>>> +}
>>>> +
>>>> +int test_run(struct tdescr *td)
>>>> +{
>>>> +	if (td->sig_trig) {
>>>> +		if (td->trigger)
>>>> +			return td->trigger(td);
>>>> +		else
>>>> +			return default_trigger(td);
>>>> +	} else {
>>>> +		return td->run(td, NULL, NULL);
>>>> +	}
>>>> +}
>>>> +
>>>> +void test_result(struct tdescr *td)
>>>> +{
>>>> +	if (td->check_result)
>>>> +		td->check_result(td);
>>>> +	default_result(td, 0);
>>>> +}
>>>> +
>>>> +void test_cleanup(struct tdescr *td)
>>>> +{
>>>> +	if (td->cleanup)
>>>> +		td->cleanup(td);
>>>> +}
>>>> diff --git a/tools/testing/selftests/arm64/signal/test_signals_utils.h b/tools/testing/selftests/arm64/signal/test_signals_utils.h
>>>> new file mode 100644
>>>> index 000000000000..8658d1a7d4b9
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/arm64/signal/test_signals_utils.h
>>>> @@ -0,0 +1,13 @@
>>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>>> +/* Copyright (C) 2019 ARM Limited */
>>>> +
>>>> +#ifndef __TEST_SIGNALS_UTILS_H__
>>>> +#define __TEST_SIGNALS_UTILS_H__
>>>> +
>>>> +#include "test_signals.h"
>>>> +
>>>> +int test_setup(struct tdescr *td);
>>>> +void test_cleanup(struct tdescr *td);
>>>> +int test_run(struct tdescr *td);
>>>> +void test_result(struct tdescr *td);
>>>> +#endif
>>>> diff --git a/tools/testing/selftests/arm64/signal/testcases/.gitignore b/tools/testing/selftests/arm64/signal/testcases/.gitignore
>>>> new file mode 100644
>>>> index 000000000000..8651272e3cfc
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/arm64/signal/testcases/.gitignore
>>>> @@ -0,0 +1 @@
>>>> +mangle_pstate_invalid_compat_toggle
>>>> diff --git a/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_compat_toggle.c b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_compat_toggle.c
>>>> new file mode 100644
>>>> index 000000000000..971193e7501b
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_compat_toggle.c
>>>> @@ -0,0 +1,25 @@
>>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>>> +/* Copyright (C) 2019 ARM Limited */
>>>> +
>>>> +#include "test_signals_utils.h"
>>>> +#include "testcases.h"
>>>> +
>>>> +static int mangle_invalid_pstate_run(struct tdescr *td, siginfo_t *si,
>>>> +				     ucontext_t *uc)
>>>> +{
>>>> +	ASSERT_GOOD_CONTEXT(uc);
>>>> +
>>>> +	/* This config should trigger a SIGSEGV by Kernel */
>>>> +	uc->uc_mcontext.pstate ^= PSR_MODE32_BIT;
>>>> +
>>>> +	return 1;
>>>> +}
>>>> +
>>>> +struct tdescr tde = {
>>>> +		.sanity_disabled = true,
>>>> +		.name = "MANGLE_PSTATE_INVALID_STATE_TOGGLE",
>>>> +		.descr = "Mangling uc_mcontext with INVALID STATE_TOGGLE",
>>>> +		.sig_trig = SIGUSR1,
>>>> +		.sig_ok = SIGSEGV,
>>>> +		.run = mangle_invalid_pstate_run,
>>>> +};
>>>> diff --git a/tools/testing/selftests/arm64/signal/testcases/testcases.c b/tools/testing/selftests/arm64/signal/testcases/testcases.c
>>>> new file mode 100644
>>>> index 000000000000..a59785092e1f
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/arm64/signal/testcases/testcases.c
>>>> @@ -0,0 +1,150 @@
>>>> +#include "testcases.h"
>>>> +
>>>> +struct _aarch64_ctx *get_header(struct _aarch64_ctx *head, uint32_t magic,
>>>> +				size_t resv_sz, size_t *offset)
>>>> +{
>>>> +	size_t offs = 0;
>>>> +	struct _aarch64_ctx *found = NULL;
>>>> +
>>>> +	if (!head || resv_sz < HDR_SZ)
>>>> +		return found;
>>>> +
>>>> +	do {
>>>> +		if (head->magic == magic) {
>>>> +			found = head;
>>>> +			break;
>>>> +		}
>>>> +		offs += head->size;
>>>> +		head = GET_RESV_NEXT_HEAD(head);
>>>> +	} while (offs < resv_sz - HDR_SZ);
>>>> +
>>>> +	if (offset)
>>>> +		*offset = offs;
>>>> +
>>>> +	return found;
>>>> +}
>>>> +
>>>> +bool validate_extra_context(struct extra_context *extra, char **err)
>>>> +{
>>>> +	struct _aarch64_ctx *term;
>>>> +
>>>> +	if (!extra || !err)
>>>> +		return false;
>>>> +
>>>> +	fprintf(stderr, "Validating EXTRA...\n");
>>>> +	term = GET_RESV_NEXT_HEAD(extra);
>>>> +	if (!term || term->magic || term->size) {
>>>> +		*err = "UN-Terminated EXTRA context";
>>>> +		return false;
>>>> +	}
>>>> +	if (extra->datap & 0x0fUL)
>>>> +		*err = "Extra DATAP misaligned";
>>>> +	else if (extra->size & 0x0fUL)
>>>> +		*err = "Extra SIZE misaligned";
>>>> +	else if (extra->datap != (uint64_t)term + sizeof(*term))
>>>> +		*err = "Extra DATAP misplaced (not contiguos)";
>>>> +	if (*err)
>>>> +		return false;
>>>> +
>>>> +	return true;
>>>> +}
>>>> +
>>>> +bool validate_reserved(ucontext_t *uc, size_t resv_sz, char **err)
>>>> +{
>>>> +	bool terminated = false;
>>>> +	size_t offs = 0;
>>>> +	int flags = 0;
>>>> +	struct extra_context *extra = NULL;
>>>> +	struct _aarch64_ctx *head =
>>>> +		(struct _aarch64_ctx *)uc->uc_mcontext.__reserved;
>>>> +
>>>> +	if (!err)
>>>> +		return false;
>>>> +	/* Walk till the end terminator verifying __reserved contents */
>>>> +	while (head && !terminated && offs < resv_sz) {
>>>> +		if ((uint64_t)head & 0x0fUL) {
>>>> +			*err = "Misaligned HEAD";
>>>> +			return false;
>>>> +		}
>>>> +
>>>> +		switch (head->magic) {
>>>> +			case 0:
>>>> +				if (head->size)
>>>> +					*err = "Bad size for MAGIC0";
>>>> +				else
>>>> +					terminated = true;
>>>> +				break;
>>>> +			case FPSIMD_MAGIC:
>>>> +				if (flags & FPSIMD_CTX)
>>>> +					*err = "Multiple FPSIMD_MAGIC";
>>>> +				else if (head->size !=
>>>> +					 sizeof(struct fpsimd_context))
>>>> +					*err = "Bad size for fpsimd_context";
>>>> +				flags |= FPSIMD_CTX;
>>>> +				break;
>>>> +			case ESR_MAGIC:
>>>> +				if (head->size != sizeof(struct esr_context))
>>>> +					fprintf(stderr,
>>>> +						"Bad size for esr_context is not an error...just ignore.\n");
>>>> +				break;
>>>> +			case SVE_MAGIC:
>>>> +				if (flags & SVE_CTX)
>>>> +					*err = "Multiple SVE_MAGIC";
>>>> +				else if (head->size !=
>>>> +					 sizeof(struct sve_context))
>>>> +					*err = "Bad size for sve_context";
>>>> +				flags |= SVE_CTX;
>>>> +				break;
>>>> +			case EXTRA_MAGIC:
>>>> +				if (flags & EXTRA_CTX)
>>>> +					*err = "Multiple EXTRA_MAGIC";
>>>> +				else if (head->size !=
>>>> +					 sizeof(struct extra_context))
>>>> +					*err = "Bad size for extra_context";
>>>> +				flags |= EXTRA_CTX;
>>>> +				extra = (struct extra_context *)head;
>>>> +				break;
>>>> +			case KSFT_BAD_MAGIC:
>>>> +				/*
>>>> +				 * This is a BAD magic header defined
>>>> +				 * artificially by a testcase and surely
>>>> +				 * unknown to the Kernel parse_user_sigframe().
>>>> +				 * It MUST cause a Kernel induced SEGV
>>>> +				 */
>>>> +				*err = "BAD MAGIC !";
>>>> +				break;
>>>> +			default:
>>>> +				/*
>>>> +				 * A still unknown Magic: potentially freshly added
>>>> +				 * to the Kernel code and still unknown to the
>>>> +				 * tests.
>>>> +				 */
>>>> +				fprintf(stdout,
>>>> +					"SKIP Unknown MAGIC: 0x%X - Is KSFT arm64/signal up to date ?\n",
>>>> +					head->magic);
>>>> +				break;
>>>> +		}
>>>> +
>>>> +		if (*err)
>>>> +			return false;
>>>> +
>>>> +		offs += head->size;
>>>> +		if (resv_sz - offs < sizeof(*head)) {
>>>> +			*err = "HEAD Overrun";
>>>> +			return false;
>>>> +		}
>>>> +
>>>> +		if (flags & EXTRA_CTX)
>>>> +			if (!validate_extra_context(extra, err))
>>>> +				return false;
>>>> +
>>>> +		head = GET_RESV_NEXT_HEAD(head);
>>>> +	}
>>>> +
>>>> +	if (terminated && !(flags & FPSIMD_CTX)) {
>>>> +		*err = "Missing FPSIMD";
>>>> +		return false;
>>>> +	}
>>>> +
>>>> +	return true;
>>>> +}
>>>> diff --git a/tools/testing/selftests/arm64/signal/testcases/testcases.h b/tools/testing/selftests/arm64/signal/testcases/testcases.h
>>>> new file mode 100644
>>>> index 000000000000..624717c71b1d
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/arm64/signal/testcases/testcases.h
>>>> @@ -0,0 +1,83 @@
>>>> +#ifndef __TESTCASES_H__
>>>> +#define __TESTCASES_H__
>>>> +
>>>> +#include <stdio.h>
>>>> +#include <stdbool.h>
>>>> +#include <stdint.h>
>>>> +#include <unistd.h>
>>>> +#include <ucontext.h>
>>>> +#include <assert.h>
>>>> +
>>>> +/* Architecture specific sigframe definitions */
>>>> +#include <asm/sigcontext.h>
>>>> +
>>>> +#define FPSIMD_CTX	(1 << 0)
>>>> +#define SVE_CTX		(1 << 1)
>>>> +#define EXTRA_CTX	(1 << 2)
>>>> +
>>>> +#define KSFT_BAD_MAGIC	0xdeadbeef
>>>> +
>>>> +#define HDR_SZ \
>>>> +	sizeof(struct _aarch64_ctx)
>>>> +
>>>> +#define GET_SF_RESV_HEAD(sf) \
>>>> +	(struct _aarch64_ctx *)(&(sf).uc.uc_mcontext.__reserved)
>>>> +
>>>> +#define GET_SF_RESV_SIZE(sf) \
>>>> +	sizeof((sf).uc.uc_mcontext.__reserved)
>>>> +
>>>> +#define GET_UCP_RESV_SIZE(ucp) \
>>>> +	sizeof((ucp)->uc_mcontext.__reserved)
>>>> +
>>>> +#define ASSERT_BAD_CONTEXT(uc) do {					\
>>>> +	char *err = NULL;						\
>>>> +	assert(!validate_reserved((uc), GET_UCP_RESV_SIZE((uc)), &err));\
>>>> +	if (err)							\
>>>> +		fprintf(stderr,						\
>>>> +			"Using badly built context - ERR: %s\n", err);	\
>>>> +} while(0)
>>>> +
>>>> +#define ASSERT_GOOD_CONTEXT(uc) do {					 \
>>>> +	char *err = NULL;						 \
>>>> +	if (!validate_reserved((uc), GET_UCP_RESV_SIZE((uc)), &err)) {	 \
>>>> +		if (err)						 \
>>>> +			fprintf(stderr,					 \
>>>> +				"Detected BAD context - ERR: %s\n", err);\
>>>> +		assert(0);						 \
>>>> +	} else {							 \
>>>> +		fprintf(stderr, "uc context validated.\n");		 \
>>>> +	}								 \
>>>> +} while(0)
>>>> +
>>>> +/* head->size accounts both for payload and header _aarch64_ctx size ! */
>>>> +#define GET_RESV_NEXT_HEAD(h) \
>>>> +	(struct _aarch64_ctx *)((char *)(h) + (h)->size)
>>>> +
>>>> +struct fake_sigframe {
>>>> +	siginfo_t	info;
>>>> +	ucontext_t	uc;
>>>> +};
>>>> +
>>>> +
>>>> +bool validate_reserved(ucontext_t *uc, size_t resv_sz, char **err);
>>>> +
>>>> +bool validate_extra_context(struct extra_context *extra, char **err);
>>>> +
>>>> +struct _aarch64_ctx *get_header(struct _aarch64_ctx *head, uint32_t magic,
>>>> +				size_t resv_sz, size_t *offset);
>>>> +
>>>> +static inline struct _aarch64_ctx *get_terminator(struct _aarch64_ctx *head,
>>>> +						  size_t resv_sz,
>>>> +						  size_t *offset)
>>>> +{
>>>> +	return get_header(head, 0, resv_sz, offset);
>>>> +}
>>>> +
>>>> +static inline void write_terminator_record(struct _aarch64_ctx *tail)
>>>> +{
>>>> +	if (tail) {
>>>> +		tail->magic = 0;
>>>> +		tail->size = 0;
>>>> +	}
>>>> +}
>>>> +#endif
>>>>
>>
>>

_______________________________________________
linux-arm-kernel mailing list
[email-masked]
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel