From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f201.google.com (mail-pf1-f201.google.com [209.85.210.201]) (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 A256C25B082 for ; Wed, 10 Jun 2026 00:53:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781052833; cv=none; b=QmWWdZ2AwZULDOzq9QsTVveUyqjbVEqaRX0DaIYqnSIQEhdlAFh5FWh0sgLhT2EJJK63p95WcPTelivXhnKFe9NInR+jcKTHPuEdm80J5Hz/WPYnOBanRXdkFfI/qF8fy89dItiR4y3SD/pCN0YyJUodU85epWAHNKEqoNJuyzw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781052833; c=relaxed/simple; bh=3kgZ4Hp3aocx9frJ+hGvONt/ETFM1SIvxHL3/CDxT+o=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=G6W2sZQcbFh6v8euGdTb2SV4JL2hFfuorrfh5h3AlYFxmR7zCD8RRBEU+XzJBK3N5Ca/hTq4SnXs8d4X26zT1mvXeG+hRKh/YzpsWFSwpEvTmhbjHDDoHAi49r3A3KShGkr2/tjaBATbFsm2xNDa1q6tHtdhgnTLs/GvCpOJh4Q= 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=pkxZQCBO; arc=none smtp.client-ip=209.85.210.201 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="pkxZQCBO" Received: by mail-pf1-f201.google.com with SMTP id d2e1a72fcca58-8421f5d76aaso4103175b3a.2 for ; Tue, 09 Jun 2026 17:53:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1781052831; x=1781657631; 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=uJ3/l2MPP25v59/w1QGxHHbEaCrmVOx/NA7PdBl04FQ=; b=pkxZQCBOHq+1pbkfOb0Fup7nlWHfKDVpJp5TLfy3mn+V4qCI5zG18Ko92QTFWhIe+j lw3ypmxIoMPWvjvs9Hq7Qxu0YPtI1F/8hxifvAYg7sffkdGzk+9SroguGq4GAaiabkCa R6gdRZeB4QTnUQ778Yde1XPx1pbJGUzzVx4Tl2+hQv6KV4gjkTgDnaY5KKbleUJH5ISX djuSSQfV7e8jprLZgQjpGhSX/7rPbvGTghR8HUf2zJPBAjj5uk+b60m2xT/rgUjWy7MN Jqg/BV2NLTrG9XGwqcaVXg7qyLmQJLF0n8f3hEDNKZjNGN9q124xpXpvtxXXleTzF1MN /SnQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781052831; x=1781657631; 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=uJ3/l2MPP25v59/w1QGxHHbEaCrmVOx/NA7PdBl04FQ=; b=N4bdKIfpROB0NlvauiBPzgSCGdWpGuRAYknCRjdS6z+7MeL/IMnAIhWJj5XYs1LfOX 7/Lbd+Cq7HOzcShkhTMWVRSoMs23ASlcQ8ropgZI/v0dKYwGWtahb3XrUvhb2Mxv21Za iVKPaAFyVwxSrnUDWzM0Kkq6ki3Pee7vh3LTD52j+pQVHXYFSg//UTXv8Zb8r59NRBFd Z3U3hxZ9Nyccq2ze6MiCIJDiXKaVWvdzszYoEDyH2T0KfjufTHShyBRkpy7GDwuJGCj7 H6SAAY0ypPG2d4EPOE3d4sT8yhEzqEulBFD1OKVco+wQ7uzQ3ytDUDKo6ai1cCWWsYw8 Qv/Q== X-Forwarded-Encrypted: i=1; AFNElJ+cZxZn7sQ5+e343vqw7IO2Irerh2dVG+hWfXkGQvkfBju9yQ+/fYZH9VtQX7kDZ37XKU3yGoerV3LCP6U=@vger.kernel.org X-Gm-Message-State: AOJu0YxrbSduCcGh81diUmhZgGPbHBNyb6A1/TT1PMM60rkzmbdcBnqO wvci4GJGblnVuyX8/Uy9338bnRrXU3GLKXiMMpOmCCJ1Uu4dBoTmcSGsZqzR9XtoEXkPIOSiggz PaS38gg== X-Received: from pfr9.prod.google.com ([2002:a05:6a00:94c9:b0:842:3697:8685]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:21c5:b0:831:7f71:c810 with SMTP id d2e1a72fcca58-842b0f9455fmr23501445b3a.35.1781052830791; Tue, 09 Jun 2026 17:53:50 -0700 (PDT) Reply-To: Sean Christopherson Date: Tue, 9 Jun 2026 17:53:27 -0700 In-Reply-To: <20260610005338.2967132-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260610005338.2967132-1-seanjc@google.com> X-Mailer: git-send-email 2.54.0.1099.g489fc7bff1-goog Message-ID: <20260610005338.2967132-8-seanjc@google.com> Subject: [PATCH v6 07/18] KVM: selftests: Add VFIO device support to eventfd IRQ 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 Extend the eventfd IRQ test with a '-d' argument that takes a BDF (in the format segment:bus:device.function) of an interrupt-capable PCI(e) device bound to VFIO, and use said device to trigger interrupts instead of always synthesizing interrupts via direct writes to the eventfd. Using a VFIO device to trigger interrupts validates the end-to-end delivery of IRQs for "real" devices, and when supported by hardware (and KVM), also validates interrupt delivery via IRQ bypass, i.e. via device posted IRQs. Now that IOMMUFD is a thing, auto-probe IOMMUFD vs. "legacy" VFIO by temporarily opening /dev/iommufd, and skip the test if neither IOMMUFD nor legacy VFIO is available. Add a '-t' option to the user override the probe logic, e.g. in case IOMMUFD is available but the system is configured for legacy usage. Note, the device must have a VFIO selftest driver in order to work with the test. A helper script to list supported devices will hopefully be available in the near future at tools/testing/selftests/vfio/scripts/list_supported_devices.sh[1]. Example: $ ./tools/testing/selftests/kvm/irq_test -d 0000:06:0a.1 Link: https://lore.kernel.org/all/20260602222941.3133236-1-jrhilke%40google.com [1] Signed-off-by: David Matlack Co-developed-by: Josh Hilke Signed-off-by: Josh Hilke Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson --- tools/testing/selftests/kvm/irq_test.c | 86 ++++++++++++++++++++++++-- 1 file changed, 80 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/kvm/irq_test.c b/tools/testing/selftests/kvm/irq_test.c index 9f8895b89821..6888be54ee4a 100644 --- a/tools/testing/selftests/kvm/irq_test.c +++ b/tools/testing/selftests/kvm/irq_test.c @@ -3,7 +3,10 @@ #include "test_util.h" #include "apic.h" #include "processor.h" +#include "proc_util.h" +#include +#include #include #include #include @@ -55,6 +58,36 @@ static void *vcpu_thread_main(void *arg) return NULL; } +static int vfio_setup_msi(struct vfio_pci_device *device) +{ + const int flags = MAP_SHARED | MAP_ANONYMOUS; + const int prot = PROT_READ | PROT_WRITE; + struct dma_region *region; + + /* A driver is required to generate an MSI. */ + TEST_REQUIRE(device->driver.ops); + + /* Set up a DMA-able region for the driver to use. */ + region = &device->driver.region; + region->iova = 0; + region->size = SZ_2M; + region->vaddr = kvm_mmap(region->size, prot, flags, -1); + TEST_ASSERT(region->vaddr != MAP_FAILED, "mmap() failed\n"); + iommu_map(device->iommu, region); + + vfio_pci_driver_init(device); + return device->driver.msi; +} + +static void trigger_interrupt(struct vfio_pci_device *device, int eventfd) +{ + if (device) + vfio_pci_driver_send_msi(device); + else + eventfd_write(eventfd, 1); +} + + static void kvm_route_msi(struct kvm_vm *vm, u32 gsi, struct kvm_vcpu *vcpu, u8 vector) { @@ -74,11 +107,29 @@ static void kvm_route_msi(struct kvm_vm *vm, u32 gsi, struct kvm_vcpu *vcpu, vm_ioctl(vm, KVM_SET_GSI_ROUTING, &routing.header); } +static const char *probe_iommu_type(void) +{ + int io_fd; + + io_fd = open("/dev/iommu", O_RDONLY); + if (io_fd >= 0) { + close(io_fd); + return MODE_IOMMUFD; + } + + io_fd = __open_path_or_exit("/dev/vfio", O_RDONLY, + "Is VFIO (or IOMMUFD) loaded and enabled?"); + close(io_fd); + return MODE_VFIO_TYPE1_IOMMU; +} + static void help(const char *name) { - printf("Usage: %s [-h]\n", name); + printf("Usage: %s [-d ] [-h] [-t iommu_type]\n", name); printf("\n"); printf("Tests KVM interrupt routing and delivery via irqfd.\n"); + printf("-d Use a VFIO device to send MSI-X interrupts instead of manually signaling the eventfd\n"); + printf("-t Override the IOMMU type to use (vfio_type1_iommu or iommufd)\n"); printf("\n"); exit(KSFT_FAIL); } @@ -100,14 +151,25 @@ int main(int argc, char **argv) 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]; + struct kvm_vcpu *vcpus[KVM_MAX_VCPUS]; + struct vfio_pci_device *device = NULL; int nr_irqs = 1000, nr_vcpus = 1; - int i, j, c, eventfd; + const char *device_bdf = NULL; + const char *iommu_type = NULL; + int i, j, c, msix, eventfd; + struct iommu *iommu; struct kvm_vm *vm; + int irq; - while ((c = getopt(argc, argv, "h")) != -1) { + while ((c = getopt(argc, argv, "d:ht:")) != -1) { switch (c) { + case 'd': + device_bdf = optarg; + break; + case 't': + iommu_type = optarg; + break; case 'h': default: help(argv[0]); @@ -119,7 +181,19 @@ int main(int argc, char **argv) vm = vm_create_with_vcpus(nr_vcpus, guest_code, vcpus); vm_install_exception_handler(vm, vector, guest_irq_handler); - eventfd = kvm_new_eventfd(); + if (device_bdf) { + if (!iommu_type) + iommu_type = probe_iommu_type(); + iommu = iommu_init(iommu_type); + device = vfio_pci_device_init(device_bdf, iommu); + msix = vfio_setup_msi(device); + irq = vfio_msix_to_host_irq(device_bdf, msix); + eventfd = device->msi_eventfds[msix]; + printf("Using device %s MSI-X[%d] (IRQ-%u)\n", device_bdf, msix, + irq); + } else { + eventfd = kvm_new_eventfd(); + } pr_info("Injecting interrupts for GSI %d (guest vector 0x%x) %d times\n", gsi, vector, nr_irqs); @@ -147,7 +221,7 @@ int main(int argc, char **argv) "IRQ flag for vCPU %d not clear prior to test", vcpus[j]->id); - eventfd_write(eventfd, 1); + trigger_interrupt(device, eventfd); clock_gettime(CLOCK_MONOTONIC, &start); while (!GUEST_RECEIVED_IRQ(vcpu) && -- 2.54.0.1099.g489fc7bff1-goog