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The kernel could mistake this for reset completion and proceed with MSI-X restoration. The resulting MMIO access triggered DPC containment. This series addresses four issues: 1. Reject all-ones responses in pci_dev_wait(). Use Command-register polling for VFs, whose Vendor ID legitimately reads as all ones. 2. Return -ETIMEDOUT when readiness polling expires, preventing fallback to another reset method. 3. Check configuration accessibility before restoring PCI state, while preserving driver reset callbacks. 4. Skip CXL decoder MMIO accesses when configuration is inaccessible or memory decoding is disabled. Best regards, Richard Cheng. Richard Cheng (4): PCI: Reject all-ones responses in pci_dev_wait() PCI: Return -ETIMEOUT when reset readiness polling expires PCI: Skip state restoration when configuration is inaccessible cxl/pci: Guard decoder accesses after reset drivers/cxl/pci.c | 6 ++++++ drivers/pci/pci.c | 16 +++++++++------- 2 files changed, 15 insertions(+), 7 deletions(-) base-commit: 9eb6419022d81aac6d1d9ead0e1865b451153da5 -- 2.43.0