Jason Wang 8b4ec69d7e virtio: harden vring IRQ ... This is a rework on the previous IRQ hardening that is done for virtio-pci where several drawbacks were found and were reverted: 1) try to use IRQF_NO_AUTOEN which is not friendly to affinity managed IRQ that is used by some device such as virtio-blk 2) done only for PCI transport The vq->broken is re-used in this patch for implementing the IRQ hardening. The vq->broken is set to true during both initialization and reset. And the vq->broken is set to false in virtio_device_ready(). Then vring_interrupt() can check and return when vq->broken is true. And in this case, switch to return IRQ_NONE to let the interrupt core aware of such invalid interrupt to prevent IRQ storm. The reason of using a per queue variable instead of a per device one is that we may need it for per queue reset hardening in the future. Note that the hardening is only done for vring interrupt since the config interrupt hardening is already done in commit 22b7050a02 ("virtio: defer config changed notifications"). But the method that is used by config interrupt can't be reused by the vring interrupt handler because it uses spinlock to do the synchronization which is expensive. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Marc Zyngier <maz@kernel.org> Cc: Halil Pasic <pasic@linux.ibm.com> Cc: Cornelia Huck <cohuck@redhat.com> Cc: Vineeth Vijayan <vneethv@linux.ibm.com> Cc: Peter Oberparleiter <oberpar@linux.ibm.com> Cc: linux-s390@vger.kernel.org Signed-off-by: Jason Wang <jasowang@redhat.com> Message-Id: <20220527060120.20964-9-jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>		2022-05-31 12:45:10 -04:00
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Makefile	s390: drivers: Remove redundant license text	2017-11-24 14:28:47 +01:00
virtio_ccw.c	virtio: harden vring IRQ	2022-05-31 12:45:10 -04:00