Add a test to validate the newly introduced tracefs interface for the pKVM hypervisor. This test covers the usage of extended timestamp and coherence of the tracing clock.
Signed-off-by: Vincent Donnefort <[email protected]> diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index 1a576ef28b7f..4ed5fac75981 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -84,6 +84,7 @@ enum __kvm_host_smccc_func { __KVM_HOST_SMCCC_FUNC___pkvm_enable_tracing, __KVM_HOST_SMCCC_FUNC___pkvm_swap_reader_tracing, __KVM_HOST_SMCCC_FUNC___pkvm_enable_event, + __KVM_HOST_SMCCC_FUNC___pkvm_selftest_event, }; #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] diff --git a/arch/arm64/include/asm/kvm_hypevents.h b/arch/arm64/include/asm/kvm_hypevents.h index 0b98a87a1250..1c797b748ff2 100644 --- a/arch/arm64/include/asm/kvm_hypevents.h +++ b/arch/arm64/include/asm/kvm_hypevents.h @@ -28,4 +28,14 @@ HYP_EVENT(hyp_exit, ), HE_PRINTK(" ") ); + +#ifdef CONFIG_PROTECTED_NVHE_TESTING +HYP_EVENT(selftest, + HE_PROTO(void), + HE_STRUCT(), + HE_ASSIGN(), + HE_PRINTK(" ") +); #endif + +#endif /* __ARM64_KVM_HYPEVENTS_H_ */ diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index 58f09370d17e..f3906cb733fe 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -65,4 +65,13 @@ config PROTECTED_NVHE_STACKTRACE If unsure, or not using protected nVHE (pKVM), say N. +config PROTECTED_NVHE_TESTING + bool "Protected KVM hypervisor testing infrastructure" + depends on KVM + default n + help + Say Y here to enable pKVM hypervisor testing infrastructure. + + If unsure, say N. + endif # VIRTUALIZATION diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c index f6119dbdcce1..f9991ba9744a 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -412,6 +412,19 @@ static void handle___pkvm_enable_event(struct kvm_cpu_context *host_ctxt) cpu_reg(host_ctxt, 1) = __pkvm_enable_event(id, enable); } +static void handle___pkvm_selftest_event(struct kvm_cpu_context *host_ctxt) +{ + int smc_ret = SMCCC_RET_NOT_SUPPORTED, ret = -EOPNOTSUPP; + +#ifdef CONFIG_PROTECTED_NVHE_TESTING + trace_selftest(); + smc_ret = SMCCC_RET_SUCCESS; + ret = 0; +#endif + cpu_reg(host_ctxt, 0) = smc_ret; + cpu_reg(host_ctxt, 1) = ret; +} + typedef void (*hcall_t)(struct kvm_cpu_context *); #define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x @@ -449,6 +462,7 @@ static const hcall_t host_hcall[] = { HANDLE_FUNC(__pkvm_enable_tracing), HANDLE_FUNC(__pkvm_swap_reader_tracing), HANDLE_FUNC(__pkvm_enable_event), + HANDLE_FUNC(__pkvm_selftest_event), }; static void handle_host_hcall(struct kvm_cpu_context *host_ctxt) diff --git a/arch/arm64/kvm/hyp_trace.c b/arch/arm64/kvm/hyp_trace.c index d3a14ac8b3dd..143c7edf7d17 100644 --- a/arch/arm64/kvm/hyp_trace.c +++ b/arch/arm64/kvm/hyp_trace.c @@ -765,6 +765,36 @@ static const struct file_operations hyp_trace_fops = { .release = NULL, }; +#ifdef CONFIG_PROTECTED_NVHE_TESTING +static int selftest_event_open(struct inode *inode, struct file *file) +{ + if (file->f_mode & FMODE_WRITE) + return kvm_call_hyp_nvhe(__pkvm_selftest_event); + + return 0; +} + +static ssize_t selftest_event_write(struct file *f, const char __user *buf, + size_t cnt, loff_t *pos) +{ + return cnt; +} + +static const struct file_operations selftest_event_fops = { + .open = selftest_event_open, + .write = selftest_event_write, + .llseek = no_llseek, +}; + +static void hyp_trace_init_testing_tracefs(struct dentry *root) +{ + tracefs_create_file("selftest_event", TRACEFS_MODE_WRITE, root, NULL, + &selftest_event_fops); +} +#else +static void hyp_trace_init_testing_tracefs(struct dentry *root) { } +#endif + int hyp_trace_init_tracefs(void) { struct dentry *root, *per_cpu_root; @@ -818,6 +848,7 @@ int hyp_trace_init_tracefs(void) } hyp_trace_init_event_tracefs(root); + hyp_trace_init_testing_tracefs(root); return 0; } diff --git a/tools/testing/selftests/hyp-trace/Makefile b/tools/testing/selftests/hyp-trace/Makefile new file mode 100644 index 000000000000..2a5b2e29667e --- /dev/null +++ b/tools/testing/selftests/hyp-trace/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0 +all: + +TEST_PROGS := hyp-trace-test + +include ../lib.mk diff --git a/tools/testing/selftests/hyp-trace/config b/tools/testing/selftests/hyp-trace/config new file mode 100644 index 000000000000..39cee8ec30fa --- /dev/null +++ b/tools/testing/selftests/hyp-trace/config @@ -0,0 +1,4 @@ +CONFIG_FTRACE=y +CONFIG_ARM64=y +CONFIG_KVM=y +CONFIG_PROTECTED_NVHE_TESTING=y diff --git a/tools/testing/selftests/hyp-trace/hyp-trace-test b/tools/testing/selftests/hyp-trace/hyp-trace-test new file mode 100644 index 000000000000..7f010fba385a --- /dev/null +++ b/tools/testing/selftests/hyp-trace/hyp-trace-test @@ -0,0 +1,161 @@ +#!/bin/sh -e +# SPDX-License-Identifier: GPL-2.0-only + +# hyp-trace-test - Tracefs for pKVM hypervisor test +# +# Copyright (C) 2024 - Google LLC +# Author: Vincent Donnefort <[email protected]> +# + +log_and_die() +{ + echo "$1" + + exit 1 +} + +host_clock() +{ + # BOOTTIME clock + awk '{print $1}' /proc/uptime +} + +goto_hyp_trace() +{ + if [ -d "/sys/kernel/debug/tracing/hyp" ]; then + cd /sys/kernel/debug/tracing/hyp + return + fi + + if [ -d "/sys/kernel/tracing/hyp" ]; then + cd /sys/kernel/tracing/hyp + return + fi + + echo "ERROR: hyp tracing folder not found!" + + exit 1 +} + +reset_hyp_trace() +{ + echo 0 > tracing_on + echo 0 > trace + for event in events/hyp/*; do + echo 0 > $event/enable + done +} + +setup_hyp_trace() +{ + goto_hyp_trace + + reset_hyp_trace + + echo 16 > buffer_size_kb + echo 1 > events/hyp/selftest/enable + echo 1 > tracing_on +} + +stop_hyp_trace() +{ + echo 0 > tracing_on +} + +write_events() +{ + local num="$1" + local func="$2" + + for i in $(seq 1 $num); do + echo 1 > selftest_event + [ -z "$func" -o $i -eq $num ] || eval $func + done +} + +consuming_read() +{ + local output=$1 + + nohup cat trace_pipe > $output & + + echo $! +} + +run_test_consuming() +{ + local nr_events=$1 + local func=$2 + local tmp="$(mktemp)" + local start_ts=0 + local end_ts=0 + local pid=0 + + echo "Output trace file: $tmp" + + setup_hyp_trace + pid=$(consuming_read $tmp) + + start_ts=$(host_clock) + write_events $nr_events $func + stop_hyp_trace + end_ts=$(host_clock) + + kill $pid + validate_test $tmp $nr_events $start_ts $end_ts + + rm $tmp +} + +validate_test() +{ + local output=$1 + local expected_events=$2 + local start_ts=$3 + local end_ts=$4 + local prev_ts=$3 + local ts=0 + local num_events=0 + + IFS=$'\n' + for line in $(cat $output); do + echo "$line" | grep -q -E "^# " && continue + ts=$(echo "$line" | awk '{print $2}' | cut -d ':' -f1) + if [ $(echo "$ts<$prev_ts" | bc) -eq 1 ]; then + log_and_die "Error event @$ts < $prev_ts" + fi + prev_ts=$ts + num_events=$((num_events + 1)) + done + + if [ $(echo "$ts>$end_ts" | bc) -eq 1 ]; then + log_and_die "Error event @$ts > $end_ts" + fi + + if [ $num_events -ne $expected_events ]; then + log_and_die "Expected $expected_events events, got $num_events" + fi +} + +test_base() +{ + echo "Test consuming read..." + + run_test_consuming 1000 + + echo "done." +} + +test_extended_ts() +{ + echo "Test Extended timestamp..." + + run_test_consuming 1000 "sleep 0.1" + + echo "done." +} + +test_base +test_extended_ts + +exit 0 -- 2.46.0.rc2.264.g509ed76dc8-goog
