[PATCH v2 00/15] virtio: fix spec compliance issues

From: Michael S. Tsirkin
Date: Mon Oct 06 2014 - 11:13:02 EST


Rusty, I have a mind to include this patchset for this merge window.
Any input on this?

This fixes the following virtio spec compliance issues:
1. on restore, drivers use device before setting ACKNOWLEDGE and DRIVER bits
2. on probe, drivers aren't prepared to handle config interrupts
arriving before probe returns
3. on probe, drivers use device before DRIVER_OK it set

Note that 1 is a clear violation of virtio spec 0.9 and 1.0,
so I am proposing the fix for stable. OTOH 2 is against 1.0 rules but
is a known documented bug in many drivers, so let's fix it going
forward, but it does not seem to be worth it to backport
the changes.

An error handling bugfix for virtio-net is also included.

2 is merely a theoretical race condition, but it seems important
to address to make sure that changes to address 3 do not introduce
instability.

Michael S. Tsirkin (15):
virtio_pci: fix virtio spec compliance on restore
virtio: unify config_changed handling
virtio-pci: move freeze/restore to virtio core
virtio: defer config changed notifications
virtio_blk: drop config_enable
virtio-blk: drop config_mutex
virtio_net: drop config_enable
virtio-net: drop config_mutex
virtio_net: minor cleanup
virtio: add API to enable VQs early
virtio_net: enable VQs early
virtio_blk: enable VQs early
virtio_console: enable VQs early
9p/trans_virtio: enable VQs early
virtio_net: fix use after free on allocation failure

include/linux/virtio.h | 14 +++++
include/linux/virtio_config.h | 17 +++++++
drivers/block/virtio_blk.c | 31 ++----------
drivers/char/virtio_console.c | 2 +
drivers/misc/mic/card/mic_virtio.c | 6 +--
drivers/net/virtio_net.c | 42 ++++-----------
drivers/s390/kvm/kvm_virtio.c | 9 +---
drivers/s390/kvm/virtio_ccw.c | 6 +--
drivers/virtio/virtio.c | 101 +++++++++++++++++++++++++++++++++++++
drivers/virtio/virtio_mmio.c | 7 +--
drivers/virtio/virtio_pci.c | 33 ++----------
net/9p/trans_virtio.c | 2 +
12 files changed, 159 insertions(+), 111 deletions(-)

--
MST

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