In the Linux kernel, the following vulnerability has been resolved: cxl/pci: Fix disabling memory if DVSEC CXL Range does not match a CFMWS window The Linux CXL subsystem is built on the assumption that HPA == SPA. That is, the host physical address (HPA) the HDM decoder registers are programmed with are system physical addresses (SPA). During HDM decoder setup, the DVSEC CXL range registers (cxl-3.1, 8.1.3.8) are checked if the memory is enabled and the CXL range is in a HPA window that is described in a CFMWS structure of the CXL host bridge (cxl-3.1, 9.18.1.3). Now, if the HPA is not an SPA, the CXL range does not match a CFMWS window and the CXL memory range will be disabled then. The HDM decoder stops working which causes system memory being disabled and further a system hang during HDM decoder initialization, typically when a CXL enabled kernel boots. Prevent a system hang and do not disable the HDM decoder if the decoder’s CXL range is not found in a CFMWS window. Note the change only fixes a hardware hang, but does not implement HPA/SPA translation. Support for this can be added in a follow on patch series.
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
Debian | 12 | all | linux | < 6.1.82-1 | linux_6.1.82-1_all.deb |
Debian | 11 | all | linux | < 5.10.209-2 | linux_5.10.209-2_all.deb |
Debian | 10 | all | linux | < 4.19.249-2 | linux_4.19.249-2_all.deb |
Debian | 999 | all | linux | < 6.7.7-1 | linux_6.7.7-1_all.deb |
Debian | 13 | all | linux | < 6.7.7-1 | linux_6.7.7-1_all.deb |