Hi Andrey On 24/06/2019 15:33, Andrey Konovalov wrote: > This patch is a part of a series that extends kernel ABI to allow to pass > tagged user pointers (with the top byte set to something else other than > 0x00) as syscall arguments. > > This patch adds a simple test, that calls the uname syscall with a > tagged user pointer as an argument. Without the kernel accepting tagged > user pointers the test fails with EFAULT. > > Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> > --- > tools/testing/selftests/arm64/.gitignore | 1 + > tools/testing/selftests/arm64/Makefile | 11 +++++++ > .../testing/selftests/arm64/run_tags_test.sh | 12 ++++++++ > tools/testing/selftests/arm64/tags_test.c | 29 +++++++++++++++++++ > 4 files changed, 53 insertions(+) > create mode 100644 tools/testing/selftests/arm64/.gitignore > create mode 100644 tools/testing/selftests/arm64/Makefile > create mode 100755 tools/testing/selftests/arm64/run_tags_test.sh > create mode 100644 tools/testing/selftests/arm64/tags_test.c After building a fresh Kernel from arm64/for-next-core from scratch at: commit 239ab658bea3b387424501e7c416640d6752dc0c Merge: 6bfa3134bd3a 42d038c4fb00 1243cb6a676f d55c5f28afaf d06fa5a118f1 34b5560db40d Author: Will Deacon <will@xxxxxxxxxx> Date: Thu Aug 22 18:23:53 2019 +0100 Merge branches 'for-next/error-injection', 'for-next/tbi', 'for-next/psci-cpuidle', 'for-next/cpu-topology' and 'for-next/52-bit-kva' into for-next/core KSFT arm64 tests build is broken for me, both setting or not KBUILD_OUTPUT= 13:30 $ make TARGETS=arm64 kselftest-clean make[1]: Entering directory '/home/crimar01/ARM/dev/src/pdsw/out_linux' rm -f -r /home/crimar01/ARM/dev/src/pdsw/out_linux//kselftest/arm64/tags_test make[1]: Leaving directory '/home/crimar01/ARM/dev/src/pdsw/out_linux' ✔ ~/ARM/dev/src/pdsw/linux [arm64_for_next_core|…8⚑ 23] 13:30 $ make TARGETS=arm64 kselftest make[1]: Entering directory '/home/crimar01/ARM/dev/src/pdsw/out_linux' arch/arm64/Makefile:56: CROSS_COMPILE_COMPAT not defined or empty, the compat vDSO will not be built make --no-builtin-rules INSTALL_HDR_PATH=$BUILD/usr \ ARCH=arm64 -C ../../.. headers_install HOSTCC scripts/basic/fixdep HOSTCC scripts/unifdef ... ... HDRINST usr/include/asm/msgbuf.h HDRINST usr/include/asm/shmbuf.h INSTALL /home/crimar01/ARM/dev/src/pdsw/out_linux//kselftest/usr/include /opt/toolchains/gcc-arm-8.3-2019.03-x86_64-aarch64-linux-gnu/bin/aarch64-linux-gnu-gcc tags_test.c -o /home/crimar01/ARM/dev/src/pdsw/out_linux//kselftest/arm64/tags_test tags_test.c: In function ‘main’: tags_test.c:21:12: error: ‘PR_SET_TAGGED_ADDR_CTRL’ undeclared (first use in this function); did you mean ‘PR_GET_TID_ADDRESS’? if (prctl(PR_SET_TAGGED_ADDR_CTRL, PR_TAGGED_ADDR_ENABLE, 0, 0, 0) == 0) ^~~~~~~~~~~~~~~~~~~~~~~ PR_GET_TID_ADDRESS tags_test.c:21:12: note: each undeclared identifier is reported only once for each function it appears in tags_test.c:21:37: error: ‘PR_TAGGED_ADDR_ENABLE’ undeclared (first use in this function); did you mean ‘PR_GET_DUMPABLE’? if (prctl(PR_SET_TAGGED_ADDR_CTRL, PR_TAGGED_ADDR_ENABLE, 0, 0, 0) == 0) ^~~~~~~~~~~~~~~~~~~~~ PR_GET_DUMPABLE ../lib.mk:138: recipe for target '/home/crimar01/ARM/dev/src/pdsw/out_linux//kselftest/arm64/tags_test' failed make[3]: *** [/home/crimar01/ARM/dev/src/pdsw/out_linux//kselftest/arm64/tags_test] Error 1 Makefile:136: recipe for target 'all' failed make[2]: *** [all] Error 2 /home/crimar01/ARM/dev/src/pdsw/linux/Makefile:1237: recipe for target 'kselftest' failed make[1]: *** [kselftest] Error 2 make[1]: Leaving directory '/home/crimar01/ARM/dev/src/pdsw/out_linux' Makefile:179: recipe for target 'sub-make' failed make: *** [sub-make] Error 2 Despite seeing KSFT installing Kernel Headers, they cannot be found. Fixing this patch like this make it work for me: diff --git a/tools/testing/selftests/arm64/Makefile b/tools/testing/selftests/arm64/Makefile index a61b2e743e99..f9f79fb272f0 100644 --- a/tools/testing/selftests/arm64/Makefile +++ b/tools/testing/selftests/arm64/Makefile @@ -4,6 +4,7 @@ ARCH ?= $(shell uname -m 2>/dev/null || echo not) ifneq (,$(filter $(ARCH),aarch64 arm64)) +CFLAGS += -I../../../../usr/include/ TEST_GEN_PROGS := tags_test TEST_PROGS := run_tags_test.sh endif but is not really a proper fix since it does NOT account for case in which you have installed the Kernel Headers in a non standard location like when you use KBUILD_OUTPUT. Am I missing something ? Thanks Cristian > > diff --git a/tools/testing/selftests/arm64/.gitignore b/tools/testing/selftests/arm64/.gitignore > new file mode 100644 > index 000000000000..e8fae8d61ed6 > --- /dev/null > +++ b/tools/testing/selftests/arm64/.gitignore > @@ -0,0 +1 @@ > +tags_test > diff --git a/tools/testing/selftests/arm64/Makefile b/tools/testing/selftests/arm64/Makefile > new file mode 100644 > index 000000000000..a61b2e743e99 > --- /dev/null > +++ b/tools/testing/selftests/arm64/Makefile > @@ -0,0 +1,11 @@ > +# SPDX-License-Identifier: GPL-2.0 > + > +# ARCH can be overridden by the user for cross compiling > +ARCH ?= $(shell uname -m 2>/dev/null || echo not) > + > +ifneq (,$(filter $(ARCH),aarch64 arm64)) > +TEST_GEN_PROGS := tags_test > +TEST_PROGS := run_tags_test.sh > +endif > + > +include ../lib.mk > diff --git a/tools/testing/selftests/arm64/run_tags_test.sh b/tools/testing/selftests/arm64/run_tags_test.sh > new file mode 100755 > index 000000000000..745f11379930 > --- /dev/null > +++ b/tools/testing/selftests/arm64/run_tags_test.sh > @@ -0,0 +1,12 @@ > +#!/bin/sh > +# SPDX-License-Identifier: GPL-2.0 > + > +echo "--------------------" > +echo "running tags test" > +echo "--------------------" > +./tags_test > +if [ $? -ne 0 ]; then > + echo "[FAIL]" > +else > + echo "[PASS]" > +fi > diff --git a/tools/testing/selftests/arm64/tags_test.c b/tools/testing/selftests/arm64/tags_test.c > new file mode 100644 > index 000000000000..22a1b266e373 > --- /dev/null > +++ b/tools/testing/selftests/arm64/tags_test.c > @@ -0,0 +1,29 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +#include <stdio.h> > +#include <stdlib.h> > +#include <unistd.h> > +#include <stdint.h> > +#include <sys/prctl.h> > +#include <sys/utsname.h> > + > +#define SHIFT_TAG(tag) ((uint64_t)(tag) << 56) > +#define SET_TAG(ptr, tag) (((uint64_t)(ptr) & ~SHIFT_TAG(0xff)) | \ > + SHIFT_TAG(tag)) > + > +int main(void) > +{ > + static int tbi_enabled = 0; > + struct utsname *ptr, *tagged_ptr; > + int err; > + > + if (prctl(PR_SET_TAGGED_ADDR_CTRL, PR_TAGGED_ADDR_ENABLE, 0, 0, 0) == 0) > + tbi_enabled = 1; > + ptr = (struct utsname *)malloc(sizeof(*ptr)); > + if (tbi_enabled) > + tagged_ptr = (struct utsname *)SET_TAG(ptr, 0x42); > + err = uname(tagged_ptr); > + free(ptr); > + > + return err; > +} >