From 0b1ab3aacc02e70bfe8440236eb9def426bbe10e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= Date: Wed, 12 Jul 2023 17:46:57 +0200 Subject: [PATCH 22/37] vfio/pci: Fix a segfault in vfio_realize MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Cédric Le Goater RH-MergeRequest: 179: vfio: live migration support RH-Bugzilla: 2192818 RH-Acked-by: Eric Auger RH-Acked-by: Miroslav Rezanina RH-Commit: [20/28] 48b9c1efe295c2672693d9c99f6d11738d2b98d1 (clegoate/qemu-kvm-c9s) Bugzilla: https://bugzilla.redhat.com/2192818 commit 357bd7932a13 Author: Zhenzhong Duan Date: Thu Jun 29 16:40:38 2023 +0800 vfio/pci: Fix a segfault in vfio_realize The kvm irqchip notifier is only registered if the device supports INTx, however it's unconditionally removed in vfio realize error path. If the assigned device does not support INTx, this will cause QEMU to crash when vfio realize fails. Change it to conditionally remove the notifier only if the notify hook is setup. Before fix: (qemu) device_add vfio-pci,host=81:11.1,id=vfio1,bus=root1,xres=1 Connection closed by foreign host. After fix: (qemu) device_add vfio-pci,host=81:11.1,id=vfio1,bus=root1,xres=1 Error: vfio 0000:81:11.1: xres and yres properties require display=on (qemu) Fixes: c5478fea27ac ("vfio/pci: Respond to KVM irqchip change notifier") Signed-off-by: Zhenzhong Duan Reviewed-by: Cédric Le Goater Reviewed-by: Joao Martins Signed-off-by: Cédric Le Goater Signed-off-by: Cédric Le Goater --- hw/vfio/pci.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 6634945a70..d08e6c1a20 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -3245,7 +3245,9 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) out_deregister: pci_device_set_intx_routing_notifier(&vdev->pdev, NULL); - kvm_irqchip_remove_change_notifier(&vdev->irqchip_change_notifier); + if (vdev->irqchip_change_notifier.notify) { + kvm_irqchip_remove_change_notifier(&vdev->irqchip_change_notifier); + } out_teardown: vfio_teardown_msi(vdev); vfio_bars_exit(vdev); -- 2.39.3