ira.weiny@ wrote: > From: Ira Weiny <ira.weiny@xxxxxxxxx> > > Changes from V2 > Incorporate feedback from Greg and Jonathan > > Changes from V1 > Incorporate feedback from Dan and Greg. > > PCI config space access from user space has traditionally been unrestricted > with writes being an understood risk for device operation. > > Unfortunately, device breakage or odd behavior from config writes lacks > indicators that can leave driver writers confused when evaluating failures. > This is especially true with the new PCIe Data Object Exchange (DOE) mailbox > protocol where backdoor shenanigans from user space through things such as > vendor defined protocols may affect device operation without complete breakage. > > Even though access should not be restricted it would be nice for driver writers > to be able to flag critical parts of the config space such that interference > from user space can be detected. > > Introduce pci_request_config_region_exclusive() and use it in the CXL driver > for DOE config space. > > Ira Weiny (2): > PCI: Allow drivers to request exclusive config regions > cxl/doe: Request exclusive DOE access > > drivers/cxl/pci.c | 5 +++++ > drivers/pci/pci-sysfs.c | 7 +++++++ > drivers/pci/probe.c | 6 ++++++ > include/linux/ioport.h | 2 ++ > include/linux/pci.h | 17 +++++++++++++++++ > include/uapi/linux/pci_regs.h | 1 + > kernel/resource.c | 13 ++++++++----- > 7 files changed, 46 insertions(+), 5 deletions(-) > > > base-commit: f76349cf41451c5c42a99f18a9163377e4b364ff Applied for v6.2. I am not a huge fan of the driver_exclusive_resource naming since it leaves out the configuration address space aspect. However, any other naming I can think of confuses it with the traditional PCI device resources which do more than just host exclusions.
