From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f202.google.com (mail-pg1-f202.google.com [209.85.215.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 064A920D4FC for ; Sat, 13 Jun 2026 00:20:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781310046; cv=none; b=RncLP63NopmbIPUnFiEaGPo3eWIBayIrcNIpKmTLTYUn9rWpOaLO0JU4A1RO8ciASMFbVqrGPDmR1uQA2pbZt8FbZCn+LkhbOLjn1YJ6ceJvF7q6UMf9GQhQJoxVCAllD289b9PZbBt5Z9PqRJi77dSqL08h9jD+qrOXg1e0G/g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781310046; c=relaxed/simple; bh=s0bpQt5NuHnGfmMetQxC9qly3FYJZ67mlGuCyv4j5uU=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=FDvoWHQsy2eKTwYm/DE5fzr1YaKXT+nLjdUgeOmpjxu/gzsUjknV1B3lwUzlqIyPzV03hDlNmHEQj3UJI6SHIIz3wSMdBUmPsRxtA+6WmdaHhJKdwy4oNoNl9Y2+5yX6GZuYQvf0+Fc5KOzH7KQun3s3i2cnVJRIrMFvqPoVvII= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=dNIXHJbz; arc=none smtp.client-ip=209.85.215.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="dNIXHJbz" Received: by mail-pg1-f202.google.com with SMTP id 41be03b00d2f7-c85dc345ac8so780033a12.1 for ; Fri, 12 Jun 2026 17:20:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1781310043; x=1781914843; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=AQKAT4ecSXXBBlOYiZyrbyjt8/WfFZTiCmselJ1RZro=; b=dNIXHJbzbbllCAlSc5zmKANA3l6J97rVUXhMcEcn4TX4SGdF6f4LtsOEDfP0vvJ0nB 7IC+vvkiup1YnbPPD4fjoVPRunZtbvMP0/gO+3tkLphGeYFw878v+fxVbL0qdvOqk2SI KPBTu6C7LZV+fNbbtckCwQy+Qi+Qty41rLyPsEJNWMWMDjy4bhbkpvSF8w/2kV8GuTOP Em8SdaUaOEsa5b9u5/FtKGRjZM7hH77t2/i4/jJbTKu/LH1pt4BSbeEavX1IaIEr71fV LVT3GlX+YvoojUY1+Nk4063SxFAxjIdxXQPpekEwX9Cjmgs+S4ys1Q7R5lM8XMNzsPBD d6rQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781310043; x=1781914843; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=AQKAT4ecSXXBBlOYiZyrbyjt8/WfFZTiCmselJ1RZro=; b=ZNUngj1L4VDNbDEnCTMaJMHRNtwV0X+KZj8Nb1FM8/Arzgjc2wBWk4PGOEiO+eLQsJ PDxXsbvJUyeL+weBYYMtSqsdVVJ++SHidP/YUmIvv+6cCWlR+vZMea96J4jAEJ/s33TM ui5sGttwWQKk6aJUqvmrEGDYPthjs5ekR790yIvyNm82jlcHWZ7KfSNjrMDd9RJaQoL4 jnR5iEv/qwi8bBzn+Zz9UPHiMhyvB5Pd1H2aqVpPISq3VC3PtMRKhia2I8+WekSBVmVb NIRSk2Z51AvgiDvwTujwepUwFF9PcINY7ggTJJ7WP2edKC4Ft7gK5L6OL9GDh3XOf8qv NQsg== X-Forwarded-Encrypted: i=1; AFNElJ83+T9pD3ZmuHnblkUqmlZl5aKgT4raKUNO0793WhL41HVAP+eSX2bYgAazaYPQTk+h6A7pDClVGpmDAmQ=@vger.kernel.org X-Gm-Message-State: AOJu0YzKP+BU/eusj9Dhn+vbGWLS7XMDA4WOMy792dddn+FOcHk3wzyb EqkCrcrU4OnRLJ7okCw4a4E3TP5SEIcdrUrtJIoysyK44fDpHhXQdTmZko+W+YiC4UYjJK3ltb7 tIKMIfw== X-Received: from pgo32.prod.google.com ([2002:a63:e60:0:b0:c86:2164:967d]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a20:2585:b0:3b2:924c:566e with SMTP id adf61e73a8af0-3b796421dc3mr1897654637.36.1781310043121; Fri, 12 Jun 2026 17:20:43 -0700 (PDT) Reply-To: Sean Christopherson Date: Fri, 12 Jun 2026 17:20:18 -0700 In-Reply-To: <20260613002031.745413-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260613002031.745413-1-seanjc@google.com> X-Mailer: git-send-email 2.54.0.1136.gdb2ca164c4-goog Message-ID: <20260613002031.745413-8-seanjc@google.com> Subject: [PATCH v7 07/20] KVM: selftests: Add an irqfd send+receive (and later IRQ bypass) test From: Sean Christopherson To: Paolo Bonzini , Marc Zyngier , Oliver Upton , Sean Christopherson Cc: Joey Gouly , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, David Matlack , Josh Hilke Content-Type: text/plain; charset="UTF-8" From: David Matlack Add a new test, irq_test to verify that KVM correctly delivers interrupts to a running vCPU, when triggered via an eventfd bound to a KVM GSI using KVM's irqfd mechanism. This test is intentionally simple, for now. Support for sending interrupts via VFIO devices, for IRQ bypass, and for other features will be added in the near future. Add the test in common code, even though it currently will only build and run on x86, as the concept and the bulk of the host-side code isn't specific to x86. Suggested-by: Sean Christopherson Link: https://lore.kernel.org/kvm/20250404193923.1413163-68-seanjc@google.com Signed-off-by: David Matlack Co-developed-by: Josh Hilke Signed-off-by: Josh Hilke [sean: use while() and TEST_ASSERT() instead of if-statement => TEST_FAIL()] Signed-off-by: Sean Christopherson --- tools/testing/selftests/kvm/Makefile.kvm | 1 + tools/testing/selftests/kvm/irq_test.c | 170 +++++++++++++++++++++++ 2 files changed, 171 insertions(+) create mode 100644 tools/testing/selftests/kvm/irq_test.c diff --git a/tools/testing/selftests/kvm/Makefile.kvm b/tools/testing/selftests/kvm/Makefile.kvm index 59ec232b1e93..de5f6e91203b 100644 --- a/tools/testing/selftests/kvm/Makefile.kvm +++ b/tools/testing/selftests/kvm/Makefile.kvm @@ -157,6 +157,7 @@ TEST_GEN_PROGS_x86 += coalesced_io_test TEST_GEN_PROGS_x86 += dirty_log_perf_test TEST_GEN_PROGS_x86 += guest_memfd_test TEST_GEN_PROGS_x86 += hardware_disable_test +TEST_GEN_PROGS_x86 += irq_test TEST_GEN_PROGS_x86 += mmu_stress_test TEST_GEN_PROGS_x86 += rseq_test TEST_GEN_PROGS_x86 += steal_time diff --git a/tools/testing/selftests/kvm/irq_test.c b/tools/testing/selftests/kvm/irq_test.c new file mode 100644 index 000000000000..9f8895b89821 --- /dev/null +++ b/tools/testing/selftests/kvm/irq_test.c @@ -0,0 +1,170 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "kvm_util.h" +#include "test_util.h" +#include "apic.h" +#include "processor.h" + +#include +#include +#include +#include +#include + +static u64 timeout_ns = 2ULL * 1000 * 1000 * 1000; +static bool guest_ready_for_irqs[KVM_MAX_VCPUS]; +static bool guest_received_irq[KVM_MAX_VCPUS]; +static bool done; + +#define GUEST_RECEIVED_IRQ(__vcpu) \ + SYNC_FROM_GUEST_AND_READ((__vcpu)->vm, guest_received_irq[(__vcpu)->id]) + +static u32 guest_get_vcpu_id(void) +{ + return x2apic_read_reg(APIC_ID); +} + +static void guest_irq_handler(struct ex_regs *regs) +{ + WRITE_ONCE(guest_received_irq[guest_get_vcpu_id()], true); + + x2apic_write_reg(APIC_EOI, 0); +} + +static void guest_code(void) +{ + x2apic_enable(); + + sti_nop(); + + WRITE_ONCE(guest_ready_for_irqs[guest_get_vcpu_id()], true); + + while (!READ_ONCE(done)) + cpu_relax(); + + GUEST_DONE(); +} + +static void *vcpu_thread_main(void *arg) +{ + struct kvm_vcpu *vcpu = arg; + struct ucall uc; + + vcpu_run(vcpu); + TEST_ASSERT_EQ(UCALL_DONE, get_ucall(vcpu, &uc)); + + return NULL; +} + +static void kvm_route_msi(struct kvm_vm *vm, u32 gsi, struct kvm_vcpu *vcpu, + u8 vector) +{ + struct { + struct kvm_irq_routing header; + struct kvm_irq_routing_entry entry; + } routing = { + .header.nr = 1, + .entry = { + .gsi = gsi, + .type = KVM_IRQ_ROUTING_MSI, + .u.msi.address_lo = 0xFEE00000 | (vcpu->id << 12), + .u.msi.data = vector, + }, + }; + + vm_ioctl(vm, KVM_SET_GSI_ROUTING, &routing.header); +} + +static void help(const char *name) +{ + printf("Usage: %s [-h]\n", name); + printf("\n"); + printf("Tests KVM interrupt routing and delivery via irqfd.\n"); + printf("\n"); + exit(KSFT_FAIL); +} + +int main(int argc, char **argv) +{ + /* + * Pick a random vector and a random GSI to use for device IRQ. + * + * Pick an IRQ vector in range [32, UINT8_MAX]. Min value is 32 because + * Linux/x86 reserves vectors 0-31 for exceptions and architecture + * defined NMIs and interrupts. + * + * Pick a GSI in range [24, KVM_MAX_IRQ_ROUTES - 1]. The min value is 24 + * because KVM reserves GSIs 0-15 for legacy ISA IRQs and 16-23 only go + * to the IOAPIC. The max is KVM_MAX_IRQ_ROUTES - 1, because + * KVM_MAX_IRQ_ROUTES is exclusive. + */ + u32 gsi = kvm_random_u64_in_range(&kvm_rng, 24, KVM_MAX_IRQ_ROUTES - 1); + u8 vector = kvm_random_u64_in_range(&kvm_rng, 32, UINT8_MAX); + + struct kvm_vcpu *vcpus[KVM_MAX_VCPUS]; + pthread_t vcpu_threads[KVM_MAX_VCPUS]; + int nr_irqs = 1000, nr_vcpus = 1; + int i, j, c, eventfd; + struct kvm_vm *vm; + + while ((c = getopt(argc, argv, "h")) != -1) { + switch (c) { + case 'h': + default: + help(argv[0]); + } + } + + TEST_REQUIRE(kvm_arch_has_default_irqchip()); + + vm = vm_create_with_vcpus(nr_vcpus, guest_code, vcpus); + vm_install_exception_handler(vm, vector, guest_irq_handler); + + eventfd = kvm_new_eventfd(); + + pr_info("Injecting interrupts for GSI %d (guest vector 0x%x) %d times\n", + gsi, vector, nr_irqs); + + kvm_assign_irqfd(vm, gsi, eventfd); + + for (i = 0; i < nr_vcpus; i++) + pthread_create(&vcpu_threads[i], NULL, vcpu_thread_main, vcpus[i]); + + for (i = 0; i < nr_vcpus; i++) { + struct kvm_vcpu *vcpu = vcpus[i]; + + while (!SYNC_FROM_GUEST_AND_READ(vm, guest_ready_for_irqs[vcpu->id])) + continue; + } + + for (i = 0; i < nr_irqs; i++) { + struct kvm_vcpu *vcpu = vcpus[i % nr_vcpus]; + struct timespec start; + + kvm_route_msi(vm, gsi, vcpu, vector); + + for (j = 0; j < nr_vcpus; j++) + TEST_ASSERT(!GUEST_RECEIVED_IRQ(vcpus[j]), + "IRQ flag for vCPU %d not clear prior to test", + vcpus[j]->id); + + eventfd_write(eventfd, 1); + + clock_gettime(CLOCK_MONOTONIC, &start); + while (!GUEST_RECEIVED_IRQ(vcpu) && + timespec_to_ns(timespec_elapsed(start)) <= timeout_ns) + cpu_relax(); + + TEST_ASSERT(GUEST_RECEIVED_IRQ(vcpu), + "vCPU %d timed out waiting for IRQ (vector 0x%x) from GSI %d\n", + vcpu->id, vector, gsi); + + WRITE_AND_SYNC_TO_GUEST(vm, guest_received_irq[vcpu->id], false); + } + + WRITE_AND_SYNC_TO_GUEST(vm, done, true); + + for (i = 0; i < nr_vcpus; i++) + pthread_join(vcpu_threads[i], NULL); + + return 0; +} -- 2.54.0.1136.gdb2ca164c4-goog