Fam Zheng noticed that pci shutdown disables msi and msix of a device while device is still active. This was intended to fix kexec with fusion devices but had the unintended effect of breaking even regular shutdown when using virtio. The same problem would affect any driver which doesn't register a level interrupt handler when using msix. I think the fix is to avoid touching device on shutdown: we clear bus master anyway, so we won't get any more msi interrupts, and bus reset will clear the msi/msix state eventually anyway. Patches 1-6 work well for me. Given they affect all pci devices, and the bug has been there since 2.6 times, I think there's no rush: we can merge them for 4.1. At the same time, once merged, patches 1-4 will likely make a good stable candidate: the problem was actually observed in the field, although the BZ in question isn't public yet. Patches 7-10 compiled only, will need maintainer ack. Please review, and consider at least 1-6 for 4.1. changes from v4: Yijing Wang <wangyijing@xxxxxxxxxx> noted that early fixups rely on pci_msi_off. Split out the functionality and move off the required part to run early during pci_device_setup. Changes from v3: fix a copy-and-paste error in pci: drop some duplicate code other patches are unchanged drop Cc stable for now Changes from v2: move code from probe to device enumeration add patches to unexport pci_msi_off Michael S. Tsirkin (10): pci: export functions for msi/msix ctrl pci: move pci_msi_init_pci_dev to pci.c pci: drop some duplicate code pci: don't disable msi/msix at shutdown pci: make msi/msix shutdown functions static virtio_pci: drop msi_off on probe ntb: drop pci_msi_off call on probe mic: drop pci_msi_off call on probe pci: drop pci_msi_off calls from quirks pci: unexport pci_msi_off drivers/pci/pci.h | 25 +++++++++++++++++ include/linux/pci.h | 5 ---- drivers/misc/mic/host/mic_intr.c | 2 -- drivers/ntb/ntb_hw.c | 2 -- drivers/pci/msi.c | 57 ++++++++------------------------------ drivers/pci/pci-driver.c | 2 -- drivers/pci/pci.c | 25 ++++------------- drivers/pci/probe.c | 15 ++++++++++ drivers/pci/quirks.c | 2 -- drivers/virtio/virtio_pci_common.c | 3 -- 10 files changed, 57 insertions(+), 81 deletions(-) -- MST -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
