From: Alex Williamson Date: Mon, 19 Oct 2020 13:13:55 +0000 (-0600) Subject: vfio/pci: Clear token on bypass registration failure X-Git-Tag: v5.10.7~1347^2~1 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=852b1beecb6ff9326f7ca4bc0fe69ae860ebdb9e;p=platform%2Fkernel%2Flinux-rpi.git vfio/pci: Clear token on bypass registration failure The eventfd context is used as our irqbypass token, therefore if an eventfd is re-used, our token is the same. The irqbypass code will return an -EBUSY in this case, but we'll still attempt to unregister the producer, where if that duplicate token still exists, results in removing the wrong object. Clear the token of failed producers so that they harmlessly fall out when unregistered. Fixes: 6d7425f109d2 ("vfio: Register/unregister irq_bypass_producer") Reported-by: guomin chen Tested-by: guomin chen Signed-off-by: Alex Williamson --- diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c index 1d9fb25..869dce5 100644 --- a/drivers/vfio/pci/vfio_pci_intrs.c +++ b/drivers/vfio/pci/vfio_pci_intrs.c @@ -352,11 +352,13 @@ static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev, vdev->ctx[vector].producer.token = trigger; vdev->ctx[vector].producer.irq = irq; ret = irq_bypass_register_producer(&vdev->ctx[vector].producer); - if (unlikely(ret)) + if (unlikely(ret)) { dev_info(&pdev->dev, "irq bypass producer (token %p) registration fails: %d\n", vdev->ctx[vector].producer.token, ret); + vdev->ctx[vector].producer.token = NULL; + } vdev->ctx[vector].trigger = trigger; return 0;