Message ID | 20171122121744.18697-1-vaibhav@linux.vnet.ibm.com (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
Series | [RESEND,v2] cxl: Check if vphb exists before iterating over AFU devices | expand |
Le 22/11/2017 à 13:17, Vaibhav Jain a écrit : > During an eeh a kernel-oops is reported if no vPHB to allocated to the typo, "to allocated". Not important, but.... > 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: 9e8df8a2196("cxl: EEH support") > Cc: stable@vger.kernel.org > Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> > --- > Changelog: > > Resend -> Added the 'Fixes' info and marking the patch to stable tree [Mpe] > v2 -> Added the vphb NULL check to cxl_vphb_error_detected() [Andrew] > --- > drivers/misc/cxl/pci.c | 12 ++++++++++-- > 1 file changed, 10 insertions(+), 2 deletions(-) > > diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c > index bb7fd3f4edab..18773343ab3e 100644 > --- a/drivers/misc/cxl/pci.c > +++ b/drivers/misc/cxl/pci.c > @@ -2083,6 +2083,9 @@ 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; > @@ -2124,8 +2127,7 @@ static pci_ers_result_t cxl_pci_error_detected(struct pci_dev *pdev, > * Tell the AFU drivers; but we don't care what they > * say, we're going away. > */ > - if (afu->phb != NULL) > - cxl_vphb_error_detected(afu, state); > + cxl_vphb_error_detected(afu, state); > } > return PCI_ERS_RESULT_DISCONNECT; > } > @@ -2265,6 +2267,9 @@ 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; > + > list_for_each_entry(afu_dev, &afu->phb->bus->devices, bus_list) { > /* Reset the device context. > * TODO: make this less disruptive > @@ -2327,6 +2332,9 @@ 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; > + .. that one is more annoying. afu->phb == NULL? Fred > 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) >
Frederic Barrat <fbarrat@linux.vnet.ibm.com> writes: > > .. that one is more annoying. > afu->phb == NULL? Not sure how I missed that. Thanks for catching this Fred. I have sent a v3 with the fix.
diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c index bb7fd3f4edab..18773343ab3e 100644 --- a/drivers/misc/cxl/pci.c +++ b/drivers/misc/cxl/pci.c @@ -2083,6 +2083,9 @@ 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; @@ -2124,8 +2127,7 @@ static pci_ers_result_t cxl_pci_error_detected(struct pci_dev *pdev, * Tell the AFU drivers; but we don't care what they * say, we're going away. */ - if (afu->phb != NULL) - cxl_vphb_error_detected(afu, state); + cxl_vphb_error_detected(afu, state); } return PCI_ERS_RESULT_DISCONNECT; } @@ -2265,6 +2267,9 @@ 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; + list_for_each_entry(afu_dev, &afu->phb->bus->devices, bus_list) { /* Reset the device context. * TODO: make this less disruptive @@ -2327,6 +2332,9 @@ 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)
During an eeh a kernel-oops is reported if no vPHB to 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: 9e8df8a2196("cxl: EEH support") Cc: stable@vger.kernel.org Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> --- Changelog: Resend -> Added the 'Fixes' info and marking the patch to stable tree [Mpe] v2 -> Added the vphb NULL check to cxl_vphb_error_detected() [Andrew] --- drivers/misc/cxl/pci.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)