If a device is in an error state, then any reads of device registers can return error value. Add addtional checks to validate if a device is in an error state before doing an flr reset.
Cc: stable@vger.kernel.org Reviewed-by: Benjamin Block bblock@linux.ibm.com Signed-off-by: Farhan Ali alifm@linux.ibm.com --- drivers/pci/pci.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 28c6b9e7f526..0f3ca4ff27e8 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4503,12 +4503,19 @@ EXPORT_SYMBOL_GPL(pcie_flr); */ int pcie_reset_flr(struct pci_dev *dev, bool probe) { + u32 reg; + if (dev->dev_flags & PCI_DEV_FLAGS_NO_FLR_RESET) return -ENOTTY;
if (!(dev->devcap & PCI_EXP_DEVCAP_FLR)) return -ENOTTY;
+ if (pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, ®)) { + pci_warn(dev, "Device unable to do an FLR\n"); + return -ENOTTY; + } + if (probe) return 0;