[0/6] pci-hyper: fix race condition bugs for fast device hotplug

Message

Dexuan Cui March 28, 2023, 4:51 a.m. UTC

Before the guest finishes probing a device, the host may be already starting
to remove the device. Currently there are multiple race condition bugs in the
pci-hyperv driver, which can cause the guest to panic.  The patchset fixes
the crashes.

The patchset also does some cleanup work: patch 3 removes the useless
hv_pcichild_state, and patch 4 reverts an old patch which is not really
useful (without patch 4, it would be hard to make patch 5 clean).

Patch 6 removes the use of a global mutex lock, and enables async-probing
to allow concurrent device probing for faster boot.

The patchset is also availsble in my github branch:
https://github.com/dcui/tdx/commits/decui/vpci/v6.3-rc3-v1

Please review. Thanks!

Dexuan Cui (6):
  PCI: hv: fix a race condition bug in hv_pci_query_relations()
  PCI: hv: Fix a race condition in hv_irq_unmask() that can cause panic
  PCI: hv: Remove the useless hv_pcichild_state from struct hv_pci_dev
  Revert "PCI: hv: Fix a timing issue which causes kdump to fail
    occasionally"
  PCI: hv: Add a per-bus mutex state_lock
  PCI: hv: Use async probing to reduce boot time

 drivers/pci/controller/pci-hyperv.c | 143 +++++++++++++++++-----------
 1 file changed, 85 insertions(+), 58 deletions(-)