October 2024 - Linux-kselftest-mirror

[PATCH v8 8/8] selftests/pcie_bwctrl: Create selftests

by Ilpo Järvinen

Create selftests for PCIe BW control through the PCIe cooling device sysfs interface. First, the BW control selftest finds the PCIe Port to test with. By default, the PCIe Port with the highest Link Speed is selected but another PCIe Port can be provided with -d parameter. The actual test steps the cur_state of the cooling device one-by-one from max_state to what the cur_state was initially. The speed change is confirmed by observing the current_link_speed for the corresponding PCIe Port. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen(a)linux.intel.com> --- MAINTAINERS | 1 + tools/testing/selftests/Makefile | 1 + tools/testing/selftests/pcie_bwctrl/Makefile | 2 + .../pcie_bwctrl/set_pcie_cooling_state.sh | 122 ++++++++++++++++++ .../selftests/pcie_bwctrl/set_pcie_speed.sh | 67 ++++++++++ 5 files changed, 193 insertions(+) create mode 100644 tools/testing/selftests/pcie_bwctrl/Makefile create mode 100755 tools/testing/selftests/pcie_bwctrl/set_pcie_cooling_state.sh create mode 100755 tools/testing/selftests/pcie_bwctrl/set_pcie_speed.sh diff --git a/MAINTAINERS b/MAINTAINERS index 393ed7ce5ea1..d7ffef4382df 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17940,6 +17940,7 @@ S: Supported F: drivers/pci/pcie/bwctrl.c F: drivers/thermal/pcie_cooling.c F: include/linux/pci-bwctrl.h +F: tools/testing/selftests/pcie_bwctrl/ PCIE DRIVER FOR AMAZON ANNAPURNA LABS M: Jonathan Chocron <jonnyc(a)amazon.com> diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index b38199965f99..7181756f47ff 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -72,6 +72,7 @@ TARGETS += net/packetdrill TARGETS += net/rds TARGETS += net/tcp_ao TARGETS += nsfs +TARGETS += pcie_bwctrl TARGETS += perf_events TARGETS += pidfd TARGETS += pid_namespace diff --git a/tools/testing/selftests/pcie_bwctrl/Makefile b/tools/testing/selftests/pcie_bwctrl/Makefile new file mode 100644 index 000000000000..3e84e26341d1 --- /dev/null +++ b/tools/testing/selftests/pcie_bwctrl/Makefile @@ -0,0 +1,2 @@ +TEST_PROGS = set_pcie_cooling_state.sh +include ../lib.mk diff --git a/tools/testing/selftests/pcie_bwctrl/set_pcie_cooling_state.sh b/tools/testing/selftests/pcie_bwctrl/set_pcie_cooling_state.sh new file mode 100755 index 000000000000..9df606552af3 --- /dev/null +++ b/tools/testing/selftests/pcie_bwctrl/set_pcie_cooling_state.sh @@ -0,0 +1,122 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0-or-later + +SYSFS= +# Kselftest framework requirement - SKIP code is 4. +ksft_skip=4 +retval=0 +skipmsg="skip all tests:" + +PCIEPORTTYPE="PCIe_Port_Link_Speed" + +prerequisite() +{ + local ports + + if [ $UID != 0 ]; then + echo $skipmsg must be run as root >&2 + exit $ksft_skip + fi + + SYSFS=`mount -t sysfs | head -1 | awk '{ print $3 }'` + + if [ ! -d "$SYSFS" ]; then + echo $skipmsg sysfs is not mounted >&2 + exit $ksft_skip + fi + + if ! ls $SYSFS/class/thermal/cooling_device* > /dev/null 2>&1; then + echo $skipmsg thermal cooling devices missing >&2 + exit $ksft_skip + fi + + ports=`grep -e "^$PCIEPORTTYPE" $SYSFS/class/thermal/cooling_device*/type | wc -l` + if [ $ports -eq 0 ]; then + echo $skipmsg pcie cooling devices missing >&2 + exit $ksft_skip + fi +} + +testport= +find_pcie_port() +{ + local patt="$1" + local pcieports + local max + local cur + local delta + local bestdelta=-1 + + pcieports=`grep -l -F -e "$patt" /sys/class/thermal/cooling_device*/type` + if [ -z "$pcieports" ]; then + return + fi + pcieports=${pcieports//\/type/} + # Find the port with the highest PCIe Link Speed + for port in $pcieports; do + max=`cat $port/max_state` + cur=`cat $port/cur_state` + delta=$((max-cur)) + if [ $delta -gt $bestdelta ]; then + testport="$port" + bestdelta=$delta + fi + done +} + +sysfspcidev= +find_sysfs_pci_dev() +{ + local typefile="$1/type" + local pcidir + + pcidir="$SYSFS/bus/pci/devices/`sed -e "s|^${PCIEPORTTYPE}_||g" $typefile`" + + if [ -r "$pcidir/current_link_speed" ]; then + sysfspcidev="$pcidir/current_link_speed" + fi +} + +usage() +{ + echo "Usage $0 [ -d dev ]" + echo -e "\t-d: PCIe port BDF string (e.g., 0000:00:04.0)" +} + +pattern="$PCIEPORTTYPE" +parse_arguments() +{ + while getopts d:h opt; do + case $opt in + h) + usage "$0" + exit 0 + ;; + d) + pattern="$PCIEPORTTYPE_$OPTARG" + ;; + *) + usage "$0" + exit 0 + ;; + esac + done +} + +parse_arguments "$@" +prerequisite +find_pcie_port "$pattern" +if [ -z "$testport" ]; then + echo $skipmsg "pcie cooling device not found from sysfs" >&2 + exit $ksft_skip +fi +find_sysfs_pci_dev "$testport" +if [ -z "$sysfspcidev" ]; then + echo $skipmsg "PCIe port device not found from sysfs" >&2 + exit $ksft_skip +fi + +./set_pcie_speed.sh "$testport" "$sysfspcidev" +retval=$? + +exit $retval diff --git a/tools/testing/selftests/pcie_bwctrl/set_pcie_speed.sh b/tools/testing/selftests/pcie_bwctrl/set_pcie_speed.sh new file mode 100755 index 000000000000..584596949312 --- /dev/null +++ b/tools/testing/selftests/pcie_bwctrl/set_pcie_speed.sh @@ -0,0 +1,67 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0-or-later + +set -e + +TESTNAME=set_pcie_speed + +declare -a PCIELINKSPEED=( + "2.5 GT/s PCIe" + "5.0 GT/s PCIe" + "8.0 GT/s PCIe" + "16.0 GT/s PCIe" + "32.0 GT/s PCIe" + "64.0 GT/s PCIe" +) + +# Kselftest framework requirement - SKIP code is 4. +ksft_skip=4 +retval=0 + +coolingdev="$1" +statefile="$coolingdev/cur_state" +maxfile="$coolingdev/max_state" +linkspeedfile="$2" + +oldstate=`cat $statefile` +maxstate=`cat $maxfile` + +set_state() +{ + local state=$1 + local linkspeed + local expected_linkspeed + + echo $state > $statefile + + sleep 1 + + linkspeed="`cat $linkspeedfile`" + expected_linkspeed=$((maxstate-state)) + expected_str="${PCIELINKSPEED[$expected_linkspeed]}" + if [ ! "${expected_str}" = "${linkspeed}" ]; then + echo "$TESTNAME failed: expected: ${expected_str}; got ${linkspeed}" + retval=1 + fi +} + +cleanup_skip () +{ + set_state $oldstate + exit $ksft_skip +} + +trap cleanup_skip EXIT + +echo "$TESTNAME: testing states $maxstate .. $oldstate with $coolingdev" +for i in $(seq $maxstate -1 $oldstate); do + set_state "$i" +done + +trap EXIT +if [ $retval -eq 0 ]; then + echo "$TESTNAME [PASS]" +else + echo "$TESTNAME [FAIL]" +fi +exit $retval -- 2.39.5

10 months, 2 weeks

2
1
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[PATCH v2] selftests: clone3: Use the capget and capset syscall directly

by zhouyuhang

From: zhouyuhang <zhouyuhang(a)kylinos.cn> The libcap commit aca076443591 ("Make cap_t operations thread safe.") added a __u8 mutex at the beginning of the struct _cap_struct, it changes the offset of the members in the structure that breaks the assumption made in the "struct libcap" definition in clone3_cap_checkpoint_restore.c. This will make the test fail. So use the capget and capset syscall directly and remove the libcap library dependency like the commit 663af70aabb7 ("bpf: selftests: Add helpers to directly use the capget and capset syscall") does. Signed-off-by: zhouyuhang <zhouyuhang(a)kylinos.cn> --- tools/testing/selftests/clone3/Makefile | 1 - .../clone3/clone3_cap_checkpoint_restore.c | 53 ++++++++----------- .../selftests/clone3/clone3_cap_helpers.h | 23 ++++++++ 3 files changed, 44 insertions(+), 33 deletions(-) create mode 100644 tools/testing/selftests/clone3/clone3_cap_helpers.h diff --git a/tools/testing/selftests/clone3/Makefile b/tools/testing/selftests/clone3/Makefile index 84832c369a2e..59d26e8da8d2 100644 --- a/tools/testing/selftests/clone3/Makefile +++ b/tools/testing/selftests/clone3/Makefile @@ -1,6 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 CFLAGS += -g -std=gnu99 $(KHDR_INCLUDES) -LDLIBS += -lcap TEST_GEN_PROGS := clone3 clone3_clear_sighand clone3_set_tid \ clone3_cap_checkpoint_restore diff --git a/tools/testing/selftests/clone3/clone3_cap_checkpoint_restore.c b/tools/testing/selftests/clone3/clone3_cap_checkpoint_restore.c index 3c196fa86c99..242088eeec88 100644 --- a/tools/testing/selftests/clone3/clone3_cap_checkpoint_restore.c +++ b/tools/testing/selftests/clone3/clone3_cap_checkpoint_restore.c @@ -15,7 +15,6 @@ #include <stdio.h> #include <stdlib.h> #include <stdbool.h> -#include <sys/capability.h> #include <sys/prctl.h> #include <sys/syscall.h> #include <sys/types.h> @@ -26,6 +25,7 @@ #include "../kselftest_harness.h" #include "clone3_selftests.h" +#include "clone3_cap_helpers.h" static void child_exit(int ret) { @@ -87,47 +87,36 @@ static int test_clone3_set_tid(struct __test_metadata *_metadata, return ret; } -struct libcap { - struct __user_cap_header_struct hdr; - struct __user_cap_data_struct data[2]; -}; - static int set_capability(void) { - cap_value_t cap_values[] = { CAP_SETUID, CAP_SETGID }; - struct libcap *cap; - int ret = -1; - cap_t caps; - - caps = cap_get_proc(); - if (!caps) { - perror("cap_get_proc"); + struct __user_cap_data_struct data[2]; + struct __user_cap_header_struct hdr = { + .version = _LINUX_CAPABILITY_VERSION_3, + }; + __u32 cap0 = 1 << CAP_SETUID | 1 << CAP_SETGID; + __u32 cap1 = 1 << (CAP_CHECKPOINT_RESTORE - 32); + int ret; + + ret = capget(&hdr, data); + if (ret) { + perror("capget"); return -1; } /* Drop all capabilities */ - if (cap_clear(caps)) { - perror("cap_clear"); - goto out; - } + memset(&data, 0, sizeof(data)); - cap_set_flag(caps, CAP_EFFECTIVE, 2, cap_values, CAP_SET); - cap_set_flag(caps, CAP_PERMITTED, 2, cap_values, CAP_SET); + data[0].effective |= cap0; + data[0].permitted |= cap0; - cap = (struct libcap *) caps; + data[1].effective |= cap1; + data[1].permitted |= cap1; - /* 40 -> CAP_CHECKPOINT_RESTORE */ - cap->data[1].effective |= 1 << (40 - 32); - cap->data[1].permitted |= 1 << (40 - 32); - - if (cap_set_proc(caps)) { - perror("cap_set_proc"); - goto out; + ret = capset(&hdr, data); + if (ret) { + perror("capset"); + return -1; } - ret = 0; -out: - if (cap_free(caps)) - perror("cap_free"); return ret; } diff --git a/tools/testing/selftests/clone3/clone3_cap_helpers.h b/tools/testing/selftests/clone3/clone3_cap_helpers.h new file mode 100644 index 000000000000..3fa59ef68fb8 --- /dev/null +++ b/tools/testing/selftests/clone3/clone3_cap_helpers.h @@ -0,0 +1,23 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __CLONE3_CAP_HELPERS_H +#define __CLONE3_CAP_HELPERS_H + +#include <linux/capability.h> + +/* + * Compatible with older version + * header file without defined + * CAP_CHECKPOINT_RESTORE. + */ +#ifndef CAP_CHECKPOINT_RESTORE +#define CAP_CHECKPOINT_RESTORE 40 +#endif + +/* + * Removed the libcap library dependency. + * So declare them here directly. + */ +int capget(cap_user_header_t header, cap_user_data_t data); +int capset(cap_user_header_t header, const cap_user_data_t data); + +#endif -- 2.27.0

10 months, 2 weeks

2
4
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[PATCH] selftests: mm: fix the incorrect usage() info of khugepaged

by Nanyong Sun

The mount option of tmpfs should be huge=advise, not madvise which is not supported and may mislead the users. Fixes: 1b03d0d558a2 ("selftests/vm: add thp collapse file and tmpfs testing") Signed-off-by: Nanyong Sun <sunnanyong(a)huawei.com> --- tools/testing/selftests/mm/khugepaged.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/selftests/mm/khugepaged.c index 56d4480e8d3c..8a4d34cce36b 100644 --- a/tools/testing/selftests/mm/khugepaged.c +++ b/tools/testing/selftests/mm/khugepaged.c @@ -1091,7 +1091,7 @@ static void usage(void) fprintf(stderr, "\n\t\"file,all\" mem_type requires kernel built with\n"); fprintf(stderr, "\tCONFIG_READ_ONLY_THP_FOR_FS=y\n"); fprintf(stderr, "\n\tif [dir] is a (sub)directory of a tmpfs mount, tmpfs must be\n"); - fprintf(stderr, "\tmounted with huge=madvise option for khugepaged tests to work\n"); + fprintf(stderr, "\tmounted with huge=advise option for khugepaged tests to work\n"); fprintf(stderr, "\n\tSupported Options:\n"); fprintf(stderr, "\t\t-h: This help message.\n"); fprintf(stderr, "\t\t-s: mTHP size, expressed as page order.\n"); -- 2.33.0

10 months, 2 weeks

4
4
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kselftest/fixes build: 4 builds: 1 failed, 3 passed, 1 warning (linux_kselftest-fixes-6.12-rc3-1-gfe05c40ca9c1)

by kernelci.org bot

kselftest/fixes build: 4 builds: 1 failed, 3 passed, 1 warning (linux_kselftest-fixes-6.12-rc3-1-gfe05c40ca9c1) Full Build Summary: https://kernelci.org/build/kselftest/branch/fixes/kernel/linux_kselftest-fi… Tree: kselftest Branch: fixes Git Describe: linux_kselftest-fixes-6.12-rc3-1-gfe05c40ca9c1 Git Commit: fe05c40ca9c18cfdb003f639a30fc78a7ab49519 Git URL: https://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest.git Built: 4 unique architectures Build Failure Detected: arm64: defconfig+kselftest+arm64-chromebook: (clang-16) FAIL Warnings Detected: arm64: arm: i386: x86_64: x86_64_defconfig+kselftest (clang-16): 1 warning Warnings summary: 1 vmlinux.o: warning: objtool: set_ftrace_ops_ro+0x23: relocation to !ENDBR: .text+0x14fd19 ================================================================================ Detailed per-defconfig build reports: -------------------------------------------------------------------------------- defconfig+kselftest+arm64-chromebook (arm64, clang-16) — FAIL, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- i386_defconfig+kselftest (i386, gcc-12) — PASS, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- multi_v7_defconfig+kselftest (arm, gcc-12) — PASS, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- x86_64_defconfig+kselftest (x86_64, clang-16) — PASS, 0 errors, 1 warning, 0 section mismatches Warnings: vmlinux.o: warning: objtool: set_ftrace_ops_ro+0x23: relocation to !ENDBR: .text+0x14fd19 --- For more info write to <info(a)kernelci.org>

10 months, 2 weeks

1
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[PATCH v2] selftest: hid: add the missing tests directory

by Yun Lu

Commit 160c826b4dd0 ("selftest: hid: add missing run-hid-tools-tests.sh") has added the run-hid-tools-tests.sh script for it to be installed, but I forgot to add the tests directory together. If running the test case without the tests directory, will results in the following error message: make -C tools/testing/selftests/ TARGETS=hid install \ INSTALL_PATH=$KSFT_INSTALL_PATH cd $KSFT_INSTALL_PATH ./run_kselftest.sh -t hid:hid-core.sh /usr/lib/python3.11/site-packages/_pytest/config/__init__.py:331: PluggyTeardownRaisedWarning: A plugin raised an exception during an old-style hookwrapper teardown. Plugin: helpconfig, Hook: pytest_cmdline_parse UsageError: usage: __main__.py [options] [file_or_dir] [file_or_dir] [...] __main__.py: error: unrecognized arguments: --udevd inifile: None rootdir: /root/linux/kselftest_install/hid In fact, the run-hid-tools-tests.sh script uses the scripts in the tests directory to run tests. The tests directory also needs to be added to be installed. v2: add the error message Fixes: ffb85d5c9e80 ("selftests: hid: import hid-tools hid-core tests") Cc: stable(a)vger.kernel.org Signed-off-by: Yun Lu <luyun(a)kylinos.cn> --- tools/testing/selftests/hid/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/testing/selftests/hid/Makefile b/tools/testing/selftests/hid/Makefile index 38ae31bb07b5..662209f5fabc 100644 --- a/tools/testing/selftests/hid/Makefile +++ b/tools/testing/selftests/hid/Makefile @@ -18,6 +18,7 @@ TEST_PROGS += hid-usb_crash.sh TEST_PROGS += hid-wacom.sh TEST_FILES := run-hid-tools-tests.sh +TEST_FILES += tests CXX ?= $(CROSS_COMPILE)g++ -- 2.27.0

10 months, 2 weeks

3
3
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[PATCH v2 0/3] introduce PIDFD_SELF* sentinels

by Lorenzo Stoakes

If you wish to utilise a pidfd interface to refer to the current process or thread it is rather cumbersome, requiring something like: int pidfd = pidfd_open(getpid(), 0 or PIDFD_THREAD); ... close(pidfd); Or the equivalent call opening /proc/self. It is more convenient to use a sentinel value to indicate to an interface that accepts a pidfd that we simply wish to refer to the current process thread. This series introduces sentinels for this purposes which can be passed as the pidfd in this instance rather than having to establish a dummy fd for this purpose. It is useful to refer to both the current thread from the userland's perspective for which we use PIDFD_SELF, and the current process from the userland's perspective, for which we use PIDFD_SELF_PROCESS. There is unfortunately some confusion between the kernel and userland as to what constitutes a process - a thread from the userland perspective is a process in userland, and a userland process is a thread group (more specifically the thread group leader from the kernel perspective). We therefore alias things thusly: * PIDFD_SELF_THREAD aliased by PIDFD_SELF - use PIDTYPE_PID. * PIDFD_SELF_THREAD_GROUP alised by PIDFD_SELF_PROCESS - use PIDTYPE_TGID. In all of the kernel code we refer to PIDFD_SELF_THREAD and PIDFD_SELF_THREAD_GROUP. However we expect users to use PIDFD_SELF and PIDFD_SELF_PROCESS. This matters for cases where, for instance, a user unshare()'s FDs or does thread-specific signal handling and where the user would be hugely confused if the FDs referenced or signal processed referred to the thread group leader rather than the individual thread. We ensure that pidfd_send_signal() and pidfd_getfd() work correctly, and assert as much in selftests. All other interfaces except setns() will work implicitly with this new interface, however it doesn't make sense to test waitid(P_PIDFD, ...) as waiting on ourselves is a blocking operation. In the case of setns() we explicitly disallow use of PIDFD_SELF* as it doesn't make sense to obtain the namespaces of our own process, and it would require work to implement this functionality there that would be of no use. We also do not provide the ability to utilise PIDFD_SELF* in ordinary fd operations such as open() or poll(), as this would require extensive work and be of no real use. v2: * Fix tests as reported by Shuah. * Correct RFC version lore link. Non-RFC v1: * Removed RFC tag - there seems to be general consensus that this change is a good idea, but perhaps some debate to be had on implementation. It seems sensible then to move forward with the RFC flag removed. * Introduced PIDFD_SELF_THREAD, PIDFD_SELF_THREAD_GROUP and their aliases PIDFD_SELF and PIDFD_SELF_PROCESS respectively. * Updated testing accordingly. https://lore.kernel.org/linux-mm/cover.1728578231.git.lorenzo.stoakes@oracl… RFC version: https://lore.kernel.org/linux-mm/cover.1727644404.git.lorenzo.stoakes@oracl… Lorenzo Stoakes (3): pidfd: extend pidfd_get_pid() and de-duplicate pid lookup pidfd: add PIDFD_SELF_* sentinels to refer to own thread/process selftests: pidfd: add tests for PIDFD_SELF_* include/linux/pid.h | 43 +++++- include/uapi/linux/pidfd.h | 15 ++ kernel/exit.c | 3 +- kernel/nsproxy.c | 1 + kernel/pid.c | 73 ++++++--- kernel/signal.c | 22 +-- tools/testing/selftests/pidfd/pidfd.h | 8 + .../selftests/pidfd/pidfd_getfd_test.c | 141 ++++++++++++++++++ .../selftests/pidfd/pidfd_setns_test.c | 11 ++ tools/testing/selftests/pidfd/pidfd_test.c | 76 ++++++++-- 10 files changed, 341 insertions(+), 52 deletions(-) -- 2.46.2

10 months, 2 weeks

4
12
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[PATCH 0/3] introduce PIDFD_SELF* sentinels

by Lorenzo Stoakes

If you wish to utilise a pidfd interface to refer to the current process or thread it is rather cumbersome, requiring something like: int pidfd = pidfd_open(getpid(), 0 or PIDFD_THREAD); ... close(pidfd); Or the equivalent call opening /proc/self. It is more convenient to use a sentinel value to indicate to an interface that accepts a pidfd that we simply wish to refer to the current process thread. This series introduces sentinels for this purposes which can be passed as the pidfd in this instance rather than having to establish a dummy fd for this purpose. It is useful to refer to both the current thread from the userland's perspective for which we use PIDFD_SELF, and the current process from the userland's perspective, for which we use PIDFD_SELF_PROCESS. There is unfortunately some confusion between the kernel and userland as to what constitutes a process - a thread from the userland perspective is a process in userland, and a userland process is a thread group (more specifically the thread group leader from the kernel perspective). We therefore alias things thusly: * PIDFD_SELF_THREAD aliased by PIDFD_SELF - use PIDTYPE_PID. * PIDFD_SELF_THREAD_GROUP alised by PIDFD_SELF_PROCESS - use PIDTYPE_TGID. In all of the kernel code we refer to PIDFD_SELF_THREAD and PIDFD_SELF_THREAD_GROUP. However we expect users to use PIDFD_SELF and PIDFD_SELF_PROCESS. This matters for cases where, for instance, a user unshare()'s FDs or does thread-specific signal handling and where the user would be hugely confused if the FDs referenced or signal processed referred to the thread group leader rather than the individual thread. We ensure that pidfd_send_signal() and pidfd_getfd() work correctly, and assert as much in selftests. All other interfaces except setns() will work implicitly with this new interface, however it doesn't make sense to test waitid(P_PIDFD, ...) as waiting on ourselves is a blocking operation. In the case of setns() we explicitly disallow use of PIDFD_SELF* as it doesn't make sense to obtain the namespaces of our own process, and it would require work to implement this functionality there that would be of no use. We also do not provide the ability to utilise PIDFD_SELF* in ordinary fd operations such as open() or poll(), as this would require extensive work and be of no real use. Non-RFC v1: * Removed RFC tag - there seems to be general consensus that this change is a good idea, but perhaps some debate to be had on implementation. It seems sensible then to move forward with the RFC flag removed. * Introduced PIDFD_SELF_THREAD, PIDFD_SELF_THREAD_GROUP and their aliases PIDFD_SELF and PIDFD_SELF_PROCESS respectively. * Updated testing accordingly. RFC version: https://lore.kernel.org/linux-mm/1d19f18c-5a60-44b5-a96f-9d0e74f2b02c@lucif… Lorenzo Stoakes (3): pidfd: extend pidfd_get_pid() and de-duplicate pid lookup pidfd: add PIDFD_SELF_* sentinels to refer to own thread/process selftests: pidfd: add tests for PIDFD_SELF_* include/linux/pid.h | 43 +++++- include/uapi/linux/pidfd.h | 15 ++ kernel/exit.c | 3 +- kernel/nsproxy.c | 1 + kernel/pid.c | 73 +++++++--- kernel/signal.c | 22 +-- tools/testing/selftests/pidfd/pidfd.h | 8 ++ .../selftests/pidfd/pidfd_getfd_test.c | 136 ++++++++++++++++++ .../selftests/pidfd/pidfd_setns_test.c | 11 ++ tools/testing/selftests/pidfd/pidfd_test.c | 67 +++++++-- 10 files changed, 330 insertions(+), 49 deletions(-) -- 2.46.2

10 months, 2 weeks

2
6
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[PATCH net-next v2 0/3] Threads support in proc connector

by Anjali Kulkarni

Recently we committed a fix to allow processes to receive notifications for non-zero exits via the process connector module. Commit is a4c9a56e6a2c. However, for threads, when it does a pthread_exit(&exit_status) call, the kernel is not aware of the exit status with which pthread_exit is called. It is sent by child thread to the parent process, if it is waiting in pthread_join(). Hence, for a thread exiting abnormally, kernel cannot send notifications to any listening processes. The exception to this is if the thread is sent a signal which it has not handled, and dies along with it's process as a result; for eg. SIGSEGV or SIGKILL. In this case, kernel is aware of the non-zero exit and sends a notification for it. For our use case, we cannot have parent wait in pthread_join, one of the main reasons for this being that we do not want to track normal pthread_exit(), which could be a very large number. We only want to be notified of any abnormal exits. Hence, threads are created with pthread_attr_t set to PTHREAD_CREATE_DETACHED. To fix this problem, we add a new type PROC_CN_MCAST_NOTIFY to proc connector API, which allows a thread to send it's exit status to kernel either when it needs to call pthread_exit() with non-zero value to indicate some error or from signal handler before pthread_exit(). v1->v2 changes: - Handled comment by Peter Zijlstra to remove locking for PF_EXIT_NOTIFY task->flags. - Added error handling in thread.c v->v1 changes: - Handled comment by Simon Horman to remove unused err in cn_proc.c - Handled comment by Simon Horman to make adata and key_display static in cn_hash_test.c Anjali Kulkarni (3): connector/cn_proc: Add hash table for threads connector/cn_proc: Kunit tests for threads hash table connector/cn_proc: Selftest for threads drivers/connector/Makefile | 2 +- drivers/connector/cn_hash.c | 240 ++++++++++++++++++ drivers/connector/cn_proc.c | 55 +++- drivers/connector/connector.c | 96 ++++++- include/linux/connector.h | 47 ++++ include/linux/sched.h | 2 +- include/uapi/linux/cn_proc.h | 4 +- lib/Kconfig.debug | 17 ++ lib/Makefile | 1 + lib/cn_hash_test.c | 167 ++++++++++++ lib/cn_hash_test.h | 12 + tools/testing/selftests/connector/Makefile | 23 +- .../testing/selftests/connector/proc_filter.c | 5 + tools/testing/selftests/connector/thread.c | 116 +++++++++ .../selftests/connector/thread_filter.c | 96 +++++++ 15 files changed, 873 insertions(+), 10 deletions(-) create mode 100644 drivers/connector/cn_hash.c create mode 100644 lib/cn_hash_test.c create mode 100644 lib/cn_hash_test.h create mode 100644 tools/testing/selftests/connector/thread.c create mode 100644 tools/testing/selftests/connector/thread_filter.c -- 2.46.0

10 months, 2 weeks

2
13
0 0

[v6 PATCH 1/2] hugetlb: arm64: add mte support

by Yang Shi

Enable MTE support for hugetlb. The MTE page flags will be set on the folio only. When copying hugetlb folio (for example, CoW), the tags for all subpages will be copied when copying the first subpage. When freeing hugetlb folio, the MTE flags will be cleared. Reviewed-by: Catalin Marinas <catalin.marinas(a)arm.com> Reviewed-by: David Hildenbrand <david(a)redhat.com> Signed-off-by: Yang Shi <yang(a)os.amperecomputing.com> --- arch/arm64/include/asm/hugetlb.h | 8 ++++ arch/arm64/include/asm/mman.h | 3 +- arch/arm64/include/asm/mte.h | 67 ++++++++++++++++++++++++++++++++ arch/arm64/kernel/hibernate.c | 6 +++ arch/arm64/kernel/mte.c | 27 ++++++++++++- arch/arm64/kvm/guest.c | 16 ++++++-- arch/arm64/kvm/mmu.c | 11 ++++++ arch/arm64/mm/copypage.c | 27 ++++++++++++- fs/hugetlbfs/inode.c | 2 +- 9 files changed, 159 insertions(+), 8 deletions(-) v6: * Rebased onto v6.12-rc1. * Fixed the trivial comments from David. * Collected the review tags from Catalin and David. v5: * Indentation fix and renaming per Catalin. v4: * Fixed the comment from David. v3: * Fixed the build error when !CONFIG_ARM64_MTE. * Incorporated the comment from David to have hugetlb folio specific APIs for manipulating the page flags. * Don't assume the first page is the head page since huge page copy can start from any subpage. v2: * Reimplemented the patch to fix the comments from Catalin. * Added test cases (patch #2) per Catalin. diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h index 293f880865e8..c6dff3e69539 100644 --- a/arch/arm64/include/asm/hugetlb.h +++ b/arch/arm64/include/asm/hugetlb.h @@ -11,6 +11,7 @@ #define __ASM_HUGETLB_H #include <asm/cacheflush.h> +#include <asm/mte.h> #include <asm/page.h> #ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION @@ -21,6 +22,13 @@ extern bool arch_hugetlb_migration_supported(struct hstate *h); static inline void arch_clear_hugetlb_flags(struct folio *folio) { clear_bit(PG_dcache_clean, &folio->flags); + +#ifdef CONFIG_ARM64_MTE + if (system_supports_mte()) { + clear_bit(PG_mte_tagged, &folio->flags); + clear_bit(PG_mte_lock, &folio->flags); + } +#endif } #define arch_clear_hugetlb_flags arch_clear_hugetlb_flags diff --git a/arch/arm64/include/asm/mman.h b/arch/arm64/include/asm/mman.h index 9e39217b4afb..65bc2b07f666 100644 --- a/arch/arm64/include/asm/mman.h +++ b/arch/arm64/include/asm/mman.h @@ -38,7 +38,8 @@ static inline unsigned long arch_calc_vm_flag_bits(unsigned long flags) * backed by tags-capable memory. The vm_flags may be overridden by a * filesystem supporting MTE (RAM-based). */ - if (system_supports_mte() && (flags & MAP_ANONYMOUS)) + if (system_supports_mte() && + (flags & (MAP_ANONYMOUS | MAP_HUGETLB))) return VM_MTE_ALLOWED; return 0; diff --git a/arch/arm64/include/asm/mte.h b/arch/arm64/include/asm/mte.h index 0f84518632b4..6567df8ec8ca 100644 --- a/arch/arm64/include/asm/mte.h +++ b/arch/arm64/include/asm/mte.h @@ -41,6 +41,8 @@ void mte_free_tag_storage(char *storage); static inline void set_page_mte_tagged(struct page *page) { + VM_WARN_ON_ONCE(folio_test_hugetlb(page_folio(page))); + /* * Ensure that the tags written prior to this function are visible * before the page flags update. @@ -53,6 +55,8 @@ static inline bool page_mte_tagged(struct page *page) { bool ret = test_bit(PG_mte_tagged, &page->flags); + VM_WARN_ON_ONCE(folio_test_hugetlb(page_folio(page))); + /* * If the page is tagged, ensure ordering with a likely subsequent * read of the tags. @@ -76,6 +80,8 @@ static inline bool page_mte_tagged(struct page *page) */ static inline bool try_page_mte_tagging(struct page *page) { + VM_WARN_ON_ONCE(folio_test_hugetlb(page_folio(page))); + if (!test_and_set_bit(PG_mte_lock, &page->flags)) return true; @@ -157,6 +163,67 @@ static inline int mte_ptrace_copy_tags(struct task_struct *child, #endif /* CONFIG_ARM64_MTE */ +#if defined(CONFIG_HUGETLB_PAGE) && defined(CONFIG_ARM64_MTE) +static inline void folio_set_hugetlb_mte_tagged(struct folio *folio) +{ + VM_WARN_ON_ONCE(!folio_test_hugetlb(folio)); + + /* + * Ensure that the tags written prior to this function are visible + * before the folio flags update. + */ + smp_wmb(); + set_bit(PG_mte_tagged, &folio->flags); + +} + +static inline bool folio_test_hugetlb_mte_tagged(struct folio *folio) +{ + bool ret = test_bit(PG_mte_tagged, &folio->flags); + + VM_WARN_ON_ONCE(!folio_test_hugetlb(folio)); + + /* + * If the folio is tagged, ensure ordering with a likely subsequent + * read of the tags. + */ + if (ret) + smp_rmb(); + return ret; +} + +static inline bool folio_try_hugetlb_mte_tagging(struct folio *folio) +{ + VM_WARN_ON_ONCE(!folio_test_hugetlb(folio)); + + if (!test_and_set_bit(PG_mte_lock, &folio->flags)) + return true; + + /* + * The tags are either being initialised or may have been initialised + * already. Check if the PG_mte_tagged flag has been set or wait + * otherwise. + */ + smp_cond_load_acquire(&folio->flags, VAL & (1UL << PG_mte_tagged)); + + return false; +} +#else +static inline void folio_set_hugetlb_mte_tagged(struct folio *folio) +{ +} + +static inline bool folio_test_hugetlb_mte_tagged(struct folio *folio) +{ + return false; +} + +static inline bool folio_try_hugetlb_mte_tagging(struct folio *folio) +{ + return false; +} +#endif + static inline void mte_disable_tco_entry(struct task_struct *task) { if (!system_supports_mte()) diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c index 7b11d84f533c..18749e9a6c2d 100644 --- a/arch/arm64/kernel/hibernate.c +++ b/arch/arm64/kernel/hibernate.c @@ -266,9 +266,15 @@ static int swsusp_mte_save_tags(void) max_zone_pfn = zone_end_pfn(zone); for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) { struct page *page = pfn_to_online_page(pfn); + struct folio *folio; if (!page) continue; + folio = page_folio(page); + + if (folio_test_hugetlb(folio) && + !folio_test_hugetlb_mte_tagged(folio)) + continue; if (!page_mte_tagged(page)) continue; diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c index 6174671be7c1..2fbfd27ff5f2 100644 --- a/arch/arm64/kernel/mte.c +++ b/arch/arm64/kernel/mte.c @@ -38,7 +38,24 @@ EXPORT_SYMBOL_GPL(mte_async_or_asymm_mode); void mte_sync_tags(pte_t pte, unsigned int nr_pages) { struct page *page = pte_page(pte); - unsigned int i; + struct folio *folio = page_folio(page); + unsigned long i; + + if (folio_test_hugetlb(folio)) { + unsigned long nr = folio_nr_pages(folio); + + /* Hugetlb MTE flags are set for head page only */ + if (folio_try_hugetlb_mte_tagging(folio)) { + for (i = 0; i < nr; i++, page++) + mte_clear_page_tags(page_address(page)); + folio_set_hugetlb_mte_tagged(folio); + } + + /* ensure the tags are visible before the PTE is set */ + smp_wmb(); + + return; + } /* if PG_mte_tagged is set, tags have already been initialised */ for (i = 0; i < nr_pages; i++, page++) { @@ -410,6 +427,7 @@ static int __access_remote_tags(struct mm_struct *mm, unsigned long addr, void *maddr; struct page *page = get_user_page_vma_remote(mm, addr, gup_flags, &vma); + struct folio *folio; if (IS_ERR(page)) { err = PTR_ERR(page); @@ -428,7 +446,12 @@ static int __access_remote_tags(struct mm_struct *mm, unsigned long addr, put_page(page); break; } - WARN_ON_ONCE(!page_mte_tagged(page)); + + folio = page_folio(page); + if (folio_test_hugetlb(folio)) + WARN_ON_ONCE(!folio_test_hugetlb_mte_tagged(folio)); + else + WARN_ON_ONCE(!page_mte_tagged(page)); /* limit access to the end of the page */ offset = offset_in_page(addr); diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 962f985977c2..e738a353b20e 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -1055,6 +1055,7 @@ int kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, void *maddr; unsigned long num_tags; struct page *page; + struct folio *folio; if (is_error_noslot_pfn(pfn)) { ret = -EFAULT; @@ -1068,10 +1069,13 @@ int kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, ret = -EFAULT; goto out; } + folio = page_folio(page); maddr = page_address(page); if (!write) { - if (page_mte_tagged(page)) + if ((folio_test_hugetlb(folio) && + folio_test_hugetlb_mte_tagged(folio)) || + page_mte_tagged(page)) num_tags = mte_copy_tags_to_user(tags, maddr, MTE_GRANULES_PER_PAGE); else @@ -1085,14 +1089,20 @@ int kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, * __set_ptes() in the VMM but still overriding the * tags, hence ignoring the return value. */ - try_page_mte_tagging(page); + if (folio_test_hugetlb(folio)) + folio_try_hugetlb_mte_tagging(folio); + else + try_page_mte_tagging(page); num_tags = mte_copy_tags_from_user(maddr, tags, MTE_GRANULES_PER_PAGE); /* uaccess failed, don't leave stale tags */ if (num_tags != MTE_GRANULES_PER_PAGE) mte_clear_page_tags(maddr); - set_page_mte_tagged(page); + if (folio_test_hugetlb(folio)) + folio_set_hugetlb_mte_tagged(folio); + else + set_page_mte_tagged(page); kvm_release_pfn_dirty(pfn); } diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index a509b63bd4dd..962449f9ac2f 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1401,10 +1401,21 @@ static void sanitise_mte_tags(struct kvm *kvm, kvm_pfn_t pfn, { unsigned long i, nr_pages = size >> PAGE_SHIFT; struct page *page = pfn_to_page(pfn); + struct folio *folio = page_folio(page); if (!kvm_has_mte(kvm)) return; + if (folio_test_hugetlb(folio)) { + /* Hugetlb has MTE flags set on head page only */ + if (folio_try_hugetlb_mte_tagging(folio)) { + for (i = 0; i < nr_pages; i++, page++) + mte_clear_page_tags(page_address(page)); + folio_set_hugetlb_mte_tagged(folio); + } + return; + } + for (i = 0; i < nr_pages; i++, page++) { if (try_page_mte_tagging(page)) { mte_clear_page_tags(page_address(page)); diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c index a7bb20055ce0..87b3f1a25535 100644 --- a/arch/arm64/mm/copypage.c +++ b/arch/arm64/mm/copypage.c @@ -18,15 +18,40 @@ void copy_highpage(struct page *to, struct page *from) { void *kto = page_address(to); void *kfrom = page_address(from); + struct folio *src = page_folio(from); + struct folio *dst = page_folio(to); + unsigned int i, nr_pages; copy_page(kto, kfrom); if (kasan_hw_tags_enabled()) page_kasan_tag_reset(to); - if (system_supports_mte() && page_mte_tagged(from)) { + if (!system_supports_mte()) + return; + + if (folio_test_hugetlb(src) && + folio_test_hugetlb_mte_tagged(src)) { + if (!folio_try_hugetlb_mte_tagging(dst)) + return; + + /* + * Populate tags for all subpages. + * + * Don't assume the first page is head page since + * huge page copy may start from any subpage. + */ + nr_pages = folio_nr_pages(src); + for (i = 0; i < nr_pages; i++) { + kfrom = page_address(folio_page(src, i)); + kto = page_address(folio_page(dst, i)); + mte_copy_page_tags(kto, kfrom); + } + folio_set_hugetlb_mte_tagged(dst); + } else if (page_mte_tagged(from)) { /* It's a new page, shouldn't have been tagged yet */ WARN_ON_ONCE(!try_page_mte_tagging(to)); + mte_copy_page_tags(kto, kfrom); set_page_mte_tagged(to); } diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index 5cf327337e22..f26b3b53d7de 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -110,7 +110,7 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) * way when do_mmap unwinds (may be important on powerpc * and ia64). */ - vm_flags_set(vma, VM_HUGETLB | VM_DONTEXPAND); + vm_flags_set(vma, VM_HUGETLB | VM_DONTEXPAND | VM_MTE_ALLOWED); vma->vm_ops = &hugetlb_vm_ops; ret = seal_check_write(info->seals, vma); -- 2.41.0

10 months, 2 weeks

2
2
0 0

[PATCH] kselftest/arm64: Validate that GCS push and write permissions work

by Mark Brown

Add trivial assembly programs which give themselves the appropriate permissions and then execute GCSPUSHM and GCSSTR, they will report errors by generating signals on the non-permitted instructions. Not using libc minimises the interaction with any policy set for the system but we skip on failure to get the permissions in case the system is locked down to make them inaccessible. Signed-off-by: Mark Brown <broonie(a)kernel.org> --- tools/testing/selftests/arm64/gcs/.gitignore | 2 + tools/testing/selftests/arm64/gcs/Makefile | 8 ++- tools/testing/selftests/arm64/gcs/gcspushm.S | 96 +++++++++++++++++++++++++++ tools/testing/selftests/arm64/gcs/gcsstr.S | 99 ++++++++++++++++++++++++++++ 4 files changed, 204 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/arm64/gcs/.gitignore b/tools/testing/selftests/arm64/gcs/.gitignore index 1e8d1f6b27f2b4c6f8ea26fc55094469c39616d5..bbb8e40a7e524630fadc4cffe0defff128033829 100644 --- a/tools/testing/selftests/arm64/gcs/.gitignore +++ b/tools/testing/selftests/arm64/gcs/.gitignore @@ -3,3 +3,5 @@ libc-gcs gcs-locking gcs-stress gcs-stress-thread +gcspushm +gcsstr diff --git a/tools/testing/selftests/arm64/gcs/Makefile b/tools/testing/selftests/arm64/gcs/Makefile index d8b06ca51e22a99566f982f3aad3dceb30ffe05e..d2f3497a9103fc12ebc90c7f4e33ab9b846c6c8a 100644 --- a/tools/testing/selftests/arm64/gcs/Makefile +++ b/tools/testing/selftests/arm64/gcs/Makefile @@ -6,7 +6,7 @@ # nolibc. # -TEST_GEN_PROGS := basic-gcs libc-gcs gcs-locking gcs-stress +TEST_GEN_PROGS := basic-gcs libc-gcs gcs-locking gcs-stress gcspushm gcsstr TEST_GEN_PROGS_EXTENDED := gcs-stress-thread LDLIBS+=-lpthread @@ -22,3 +22,9 @@ $(OUTPUT)/basic-gcs: basic-gcs.c $(OUTPUT)/gcs-stress-thread: gcs-stress-thread.S $(CC) -nostdlib $^ -o $@ + +$(OUTPUT)/gcspushm: gcspushm.S + $(CC) -nostdlib $^ -o $@ + +$(OUTPUT)/gcsstr: gcsstr.S + $(CC) -nostdlib $^ -o $@ diff --git a/tools/testing/selftests/arm64/gcs/gcspushm.S b/tools/testing/selftests/arm64/gcs/gcspushm.S new file mode 100644 index 0000000000000000000000000000000000000000..bbe17c1325acc85d74dd3fe7cb586900226cde4c --- /dev/null +++ b/tools/testing/selftests/arm64/gcs/gcspushm.S @@ -0,0 +1,96 @@ +// SPDX-License-Identifier: GPL-2.0-only +// +// Copyright 2024 Arm Limited +// +// Give ourselves GCS push permissions then use them + +#include <asm/unistd.h> + +/* Shadow Stack/Guarded Control Stack interface */ +#define PR_GET_SHADOW_STACK_STATUS 74 +#define PR_SET_SHADOW_STACK_STATUS 75 +#define PR_LOCK_SHADOW_STACK_STATUS 76 + +# define PR_SHADOW_STACK_ENABLE (1UL << 0) +# define PR_SHADOW_STACK_WRITE (1UL << 1) +# define PR_SHADOW_STACK_PUSH (1UL << 2) + +#define KSFT_SKIP 4 + +.macro function name + .macro endfunction + .type \name, @function + .purgem endfunction + .endm +\name: +.endm + +// Print a single character x0 to stdout +// Clobbers x0-x2,x8 +function putc + str x0, [sp, #-16]! + + mov x0, #1 // STDOUT_FILENO + mov x1, sp + mov x2, #1 + mov x8, #__NR_write + svc #0 + + add sp, sp, #16 + ret +endfunction +.globl putc + +// Print a NUL-terminated string starting at address x0 to stdout +// Clobbers x0-x3,x8 +function puts + mov x1, x0 + + mov x2, #0 +0: ldrb w3, [x0], #1 + cbz w3, 1f + add x2, x2, #1 + b 0b + +1: mov w0, #1 // STDOUT_FILENO + mov x8, #__NR_write + svc #0 + + ret +endfunction +.globl puts + +// Utility macro to print a literal string +// Clobbers x0-x4,x8 +.macro puts string + .pushsection .rodata.str1.1, "aMS", @progbits, 1 +.L__puts_literal\@: .string "\string" + .popsection + + ldr x0, =.L__puts_literal\@ + bl puts +.endm + +.globl _start +function _start + // Run with GCS + mov x0, PR_SET_SHADOW_STACK_STATUS + mov x1, PR_SHADOW_STACK_ENABLE | PR_SHADOW_STACK_PUSH + mov x2, xzr + mov x3, xzr + mov x4, xzr + mov x5, xzr + mov x8, #__NR_prctl + svc #0 + cbz x0, 1f + puts "Failed to enable GCS with push permission\n" + mov x0, #KSFT_SKIP + b 2f +1: + sys #3, c7, c7, #0, x0 // GCSPUSHM + sysl x0, #3, c7, c7, #1 // GCSPOPM + + mov x0, #0 +2: + mov x8, #__NR_exit + svc #0 diff --git a/tools/testing/selftests/arm64/gcs/gcsstr.S b/tools/testing/selftests/arm64/gcs/gcsstr.S new file mode 100644 index 0000000000000000000000000000000000000000..a42bba6e30b18147887bb13046c96bd48850de2e --- /dev/null +++ b/tools/testing/selftests/arm64/gcs/gcsstr.S @@ -0,0 +1,99 @@ +// SPDX-License-Identifier: GPL-2.0-only +// +// Copyright 2024 Arm Limited +// +// Give ourselves GCS write permissions then use them + +#include <asm/unistd.h> + +/* Shadow Stack/Guarded Control Stack interface */ +#define PR_GET_SHADOW_STACK_STATUS 74 +#define PR_SET_SHADOW_STACK_STATUS 75 +#define PR_LOCK_SHADOW_STACK_STATUS 76 + +# define PR_SHADOW_STACK_ENABLE (1UL << 0) +# define PR_SHADOW_STACK_WRITE (1UL << 1) +# define PR_SHADOW_STACK_PUSH (1UL << 2) + +#define GCSPR_EL0 S3_3_C2_C5_1 + +#define KSFT_SKIP 4 + +.macro function name + .macro endfunction + .type \name, @function + .purgem endfunction + .endm +\name: +.endm + +// Print a single character x0 to stdout +// Clobbers x0-x2,x8 +function putc + str x0, [sp, #-16]! + + mov x0, #1 // STDOUT_FILENO + mov x1, sp + mov x2, #1 + mov x8, #__NR_write + svc #0 + + add sp, sp, #16 + ret +endfunction +.globl putc + +// Print a NUL-terminated string starting at address x0 to stdout +// Clobbers x0-x3,x8 +function puts + mov x1, x0 + + mov x2, #0 +0: ldrb w3, [x0], #1 + cbz w3, 1f + add x2, x2, #1 + b 0b + +1: mov w0, #1 // STDOUT_FILENO + mov x8, #__NR_write + svc #0 + + ret +endfunction +.globl puts + +// Utility macro to print a literal string +// Clobbers x0-x4,x8 +.macro puts string + .pushsection .rodata.str1.1, "aMS", @progbits, 1 +.L__puts_literal\@: .string "\string" + .popsection + + ldr x0, =.L__puts_literal\@ + bl puts +.endm + +.globl _start +function _start + // Run with GCS + mov x0, PR_SET_SHADOW_STACK_STATUS + mov x1, PR_SHADOW_STACK_ENABLE | PR_SHADOW_STACK_WRITE + mov x2, xzr + mov x3, xzr + mov x4, xzr + mov x5, xzr + mov x8, #__NR_prctl + svc #0 + cbz x0, 1f + puts "Failed to enable GCS with write permission\n" + mov x0, #KSFT_SKIP + b 2f +1: + mrs x0, GCSPR_EL0 + sub x0, x0, #8 + .inst 0xd91f1c01 // GCSSTR x1, x0 + + mov x0, #0 +2: + mov x8, #__NR_exit + svc #0 --- base-commit: bb9ae1a66c85eeb626864efd812c62026e126ec0 change-id: 20241004-arm64-gcs-test-flags-980a2ddfde6f Best regards, -- Mark Brown <broonie(a)kernel.org>

10 months, 2 weeks

2
1
0 0

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Linux-kselftest-mirror October 2024