Hi All: This is a rework on the IRQ hardening for virtio which is done previously by the following commits are reverted:
9e35276a5344 ("virtio_pci: harden MSI-X interrupts") 080cd7c3ac87 ("virtio-pci: harden INTX interrupts") The reason is that it depends on the IRQF_NO_AUTOEN which may conflict with the assumption of the affinity managed IRQ that is used by some virtio drivers. And what's more, it is only done for virtio-pci but not other transports. In this rework, I try to implement a general virtio solution which borrows the idea of the INTX hardening by re-using per virtqueue boolean vq->broken and toggle it in virtio_device_ready() and virtio_reset_device(). Then we can simply reuse the existing checks in the vring_interrupt() and return early if the driver is not ready. Note that, I only did compile test on ccw and MMIO transport. Please review. Changes since v1: - Use transport specific irq synchronization method when possible - Drop the module parameter and enable the hardening unconditonally - Tweak the barrier/ordering facilities used in the code - Reanme irq_soft_enabled to driver_ready - Avoid unnecssary IRQ synchornization (e.g during boot) Changes since V2: - add ccw and MMIO support - rename synchronize_vqs() to synchronize_cbs() - switch to re-use vq->broken instead of introducing new device attributes for the future virtqueue reset support - remove unnecssary READ_ONCE()/WRITE_ONCE() - a new patch to remove device triggerable BUG_ON() - more tweaks on the comments Changes since V3: - Rename synchornize_vqs() to synchronize_cbs() - tweak the comment for synchronize_cbs() - switch to use a dedicated helper __virtio_unbreak_device() and document it should be only used for probing - switch to use rwlick to synchornize the non airq for ccw Jason Wang (8): virtio: use virtio_reset_device() when possible virtio: introduce config op to synchronize vring callbacks virtio-pci: implement synchronize_cbs() virtio-mmio: implement synchronize_cbs() virtio-ccw: implement synchronize_cbs() virtio: allow to unbreak virtqueue virtio: harden vring IRQ virtio: use WARN_ON() to warning illegal status value Stefano Garzarella (1): virtio: use virtio_device_ready() in virtio_device_restore() drivers/s390/virtio/virtio_ccw.c | 27 +++++++++++++++++++++ drivers/virtio/virtio.c | 24 ++++++++++++------ drivers/virtio/virtio_mmio.c | 9 +++++++ drivers/virtio/virtio_pci_legacy.c | 1 + drivers/virtio/virtio_pci_modern.c | 2 ++ drivers/virtio/virtio_ring.c | 32 +++++++++++++++++++++--- include/linux/virtio.h | 1 + include/linux/virtio_config.h | 39 +++++++++++++++++++++++++++++- 8 files changed, 123 insertions(+), 12 deletions(-) -- 2.25.1 _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization