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 in v3 is dropped for now since it's a feature rather than a fix. Patch 6 will be split into two patches as suggested by Lorenzo and will be posted after the 5 patches are accepted first. The v4 addressed Lorenzo's comments and added Lorenzo' Acks to patch 1, 3 and 5. The v4 is based on v6.4-rc6, and can apply cleanly to the Hyper-V tree's hyperv-fixes branch. The patchset is also availsble in my github branch: https://github.com/dcui/tdx/commits/decui/vpci/v6.4-rc6-vpci-v4 FYI, v3 can be found here: https://lwn.net/ml/linux-kernel/20230420024037.5921-1-decui@xxxxxxxxxxxxx/ Please review. Thanks! Dexuan Cui (5): 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 drivers/pci/controller/pci-hyperv.c | 139 ++++++++++++++++------------ 1 file changed, 82 insertions(+), 57 deletions(-) -- 2.25.1
