diff options
Diffstat (limited to 'drivers/misc/cxl/vphb.c')
| -rw-r--r-- | drivers/misc/cxl/vphb.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/drivers/misc/cxl/vphb.c b/drivers/misc/cxl/vphb.c index 2eba002b580b..2930911c1e42 100644 --- a/drivers/misc/cxl/vphb.c +++ b/drivers/misc/cxl/vphb.c @@ -138,6 +138,26 @@ static int cxl_pcie_config_info(struct pci_bus *bus, unsigned int devfn, return 0; } + +static inline bool cxl_config_link_ok(struct pci_bus *bus) +{ + struct pci_controller *phb; + struct cxl_afu *afu; + + /* Config space IO is based on phb->cfg_addr, which is based on + * afu_desc_mmio. This isn't safe to read/write when the link + * goes down, as EEH tears down MMIO space. + * + * Check if the link is OK before proceeding. + */ + + phb = pci_bus_to_host(bus); + if (phb == NULL) + return false; + afu = (struct cxl_afu *)phb->private_data; + return cxl_adapter_link_ok(afu->adapter); +} + static int cxl_pcie_read_config(struct pci_bus *bus, unsigned int devfn, int offset, int len, u32 *val) { @@ -150,6 +170,9 @@ static int cxl_pcie_read_config(struct pci_bus *bus, unsigned int devfn, if (rc) return rc; + if (!cxl_config_link_ok(bus)) + return PCIBIOS_DEVICE_NOT_FOUND; + /* Can only read 32 bits */ *val = (in_le32(ioaddr) >> shift) & mask; return PCIBIOS_SUCCESSFUL; @@ -167,6 +190,9 @@ static int cxl_pcie_write_config(struct pci_bus *bus, unsigned int devfn, if (rc) return rc; + if (!cxl_config_link_ok(bus)) + return PCIBIOS_DEVICE_NOT_FOUND; + /* Can only write 32 bits so do read-modify-write */ mask <<= shift; val <<= shift; |