From 5fc8d62d1921062a26e8371ec4446bb760b60ead Mon Sep 17 00:00:00 2001 From: Vaibhav Jain Date: Thu, 23 Nov 2017 09:08:57 +0530 Subject: cxl: Check if vphb exists before iterating over AFU devices commit 12841f87b7a8ceb3d54f171660f72a86941bfcb3 upstream. During an eeh a kernel-oops is reported if no vPHB is allocated to the AFU. This happens as during AFU init, an error in creation of vPHB is a non-fatal error. Hence afu->phb should always be checked for NULL before iterating over it for the virtual AFU pci devices. This patch fixes the kenel-oops by adding a NULL pointer check for afu->phb before it is dereferenced. Fixes: 9e8df8a21963 ("cxl: EEH support") Signed-off-by: Vaibhav Jain Acked-by: Andrew Donnellan Acked-by: Frederic Barrat Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- drivers/misc/cxl/pci.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'drivers/misc/cxl/pci.c') diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c index 0c6c17a1c59e..ba2f6d1d7db7 100644 --- a/drivers/misc/cxl/pci.c +++ b/drivers/misc/cxl/pci.c @@ -1329,6 +1329,9 @@ static pci_ers_result_t cxl_vphb_error_detected(struct cxl_afu *afu, /* There should only be one entry, but go through the list * anyway */ + if (afu->phb == NULL) + return result; + list_for_each_entry(afu_dev, &afu->phb->bus->devices, bus_list) { if (!afu_dev->driver) continue; @@ -1369,6 +1372,10 @@ static pci_ers_result_t cxl_pci_error_detected(struct pci_dev *pdev, */ for (i = 0; i < adapter->slices; i++) { afu = adapter->afu[i]; + /* + * Tell the AFU drivers; but we don't care what they + * say, we're going away. + */ cxl_vphb_error_detected(afu, state); } return PCI_ERS_RESULT_DISCONNECT; @@ -1492,6 +1499,9 @@ static pci_ers_result_t cxl_pci_slot_reset(struct pci_dev *pdev) if (cxl_afu_select_best_mode(afu)) goto err; + if (afu->phb == NULL) + continue; + cxl_pci_vphb_reconfigure(afu); list_for_each_entry(afu_dev, &afu->phb->bus->devices, bus_list) { @@ -1556,6 +1566,9 @@ static void cxl_pci_resume(struct pci_dev *pdev) for (i = 0; i < adapter->slices; i++) { afu = adapter->afu[i]; + if (afu->phb == NULL) + continue; + list_for_each_entry(afu_dev, &afu->phb->bus->devices, bus_list) { if (afu_dev->driver && afu_dev->driver->err_handler && afu_dev->driver->err_handler->resume) -- cgit v1.2.3