@@ -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[]
@@ -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_ */
@@ -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
@@ -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)
@@ -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;
}
new file mode 100644
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+all:
+
+TEST_PROGS := hyp-trace-test
+
+include ../lib.mk
new file mode 100644
@@ -0,0 +1,4 @@
+CONFIG_FTRACE=y
+CONFIG_ARM64=y
+CONFIG_KVM=y
+CONFIG_PROTECTED_NVHE_TESTING=y
new file mode 100644
@@ -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 <vdonnefort@google.com>
+#
+
+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
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 <vdonnefort@google.com>