From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44889) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eimSS-0004eE-OR for qemu-devel@nongnu.org; Mon, 05 Feb 2018 14:29:42 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eimSR-000553-FH for qemu-devel@nongnu.org; Mon, 05 Feb 2018 14:29:40 -0500 Received: from mail-wm0-x244.google.com ([2a00:1450:400c:c09::244]:55659) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1eimSR-00054g-7n for qemu-devel@nongnu.org; Mon, 05 Feb 2018 14:29:39 -0500 Received: by mail-wm0-x244.google.com with SMTP id 143so28225646wma.5 for ; Mon, 05 Feb 2018 11:29:39 -0800 (PST) Sender: Paolo Bonzini From: Paolo Bonzini Date: Mon, 5 Feb 2018 20:28:42 +0100 Message-Id: <1517858941-5538-29-git-send-email-pbonzini@redhat.com> In-Reply-To: <1517858941-5538-1-git-send-email-pbonzini@redhat.com> References: <1517858941-5538-1-git-send-email-pbonzini@redhat.com> Subject: [Qemu-devel] [PULL 28/47] ivshmem: Improve MSI irqfd error handling List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Ladi Prosek From: Ladi Prosek Adds a rollback path to ivshmem_enable_irqfd() and fixes ivshmem_disable_irqfd() to bail if irqfd has not been enabled. To reproduce, run: ivshmem-server -n 0 and QEMU with: -device ivshmem-doorbell,chardev=iv -chardev socket,path=/tmp/ivshmem_socket,id=iv then load, unload, and load again the Windows driver, at the time of writing available at: https://github.com/virtio-win/kvm-guest-drivers-windows/tree/master/ivshmem The issue is believed to have been masked by other guest drivers, notably Linux ones, not enabling MSI-X on the device. Signed-off-by: Ladi Prosek Reviewed-by: Markus Armbruster Message-Id: <20171211072110.9058-4-lprosek@redhat.com> Signed-off-by: Paolo Bonzini --- hw/misc/ivshmem.c | 37 ++++++++++++++++++++++++------------- 1 file changed, 24 insertions(+), 13 deletions(-) diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c index 95e85e4..fe1d8d1 100644 --- a/hw/misc/ivshmem.c +++ b/hw/misc/ivshmem.c @@ -785,6 +785,20 @@ static int ivshmem_setup_interrupts(IVShmemState *s, Error **errp) return 0; } +static void ivshmem_remove_kvm_msi_virq(IVShmemState *s, int vector) +{ + IVSHMEM_DPRINTF("ivshmem_remove_kvm_msi_virq vector:%d\n", vector); + + if (s->msi_vectors[vector].pdev == NULL) { + return; + } + + /* it was cleaned when masked in the frontend. */ + kvm_irqchip_release_virq(kvm_state, s->msi_vectors[vector].virq); + + s->msi_vectors[vector].pdev = NULL; +} + static void ivshmem_enable_irqfd(IVShmemState *s) { PCIDevice *pdev = PCI_DEVICE(s); @@ -796,7 +810,7 @@ static void ivshmem_enable_irqfd(IVShmemState *s) ivshmem_add_kvm_msi_virq(s, i, &err); if (err) { error_report_err(err); - /* TODO do we need to handle the error? */ + goto undo; } } @@ -805,21 +819,14 @@ static void ivshmem_enable_irqfd(IVShmemState *s) ivshmem_vector_mask, ivshmem_vector_poll)) { error_report("ivshmem: msix_set_vector_notifiers failed"); + goto undo; } -} + return; -static void ivshmem_remove_kvm_msi_virq(IVShmemState *s, int vector) -{ - IVSHMEM_DPRINTF("ivshmem_remove_kvm_msi_virq vector:%d\n", vector); - - if (s->msi_vectors[vector].pdev == NULL) { - return; +undo: + while (--i >= 0) { + ivshmem_remove_kvm_msi_virq(s, i); } - - /* it was cleaned when masked in the frontend. */ - kvm_irqchip_release_virq(kvm_state, s->msi_vectors[vector].virq); - - s->msi_vectors[vector].pdev = NULL; } static void ivshmem_disable_irqfd(IVShmemState *s) @@ -827,6 +834,10 @@ static void ivshmem_disable_irqfd(IVShmemState *s) PCIDevice *pdev = PCI_DEVICE(s); int i; + if (!pdev->msix_vector_use_notifier) { + return; + } + msix_unset_vector_notifiers(pdev); for (i = 0; i < s->peers[s->vm_id].nb_eventfds; i++) { -- 1.8.3.1