Per Richard Lary's testing, this is not an issue with the latest kernel. http://www.spinics.net/lists/linux-pci/msg11350.html Thanks, Jon On Fri, Jul 1, 2011 at 10:08 AM, Jon Mason <jdmason@xxxxxxxx> wrote: > pci_is_pcie checks for a PCI-E capability offset that was determined > by calling pci_find_capability during the PCI bus walking. Based on > your description above this should be functionally equivalent. If > this is not safe, then the PCI bus walking code is most likely busted > on EEH enabled PPC systems (and that is a BIG problem). > > Thanks, > Jon > > On Fri, Jul 1, 2011 at 9:49 AM, James Smart <james.smart@xxxxxxxxxx> wrote: >> All, >> >> I wanted to communicate a potential warning to those drivers that had a >> patch submitted to replace config space searches of PCI_CAP_ID_EXP with >> shorthand options such as is_pcie and pci_is_pcie(). >> >> Testing with the lpfc driver and AER/EEH identified cases where the >> short-hand search options would fail on PPC platforms. The only successful >> option in all cases was the explicit search via PCI_CAP_ID_EXP. Therefore, >> I recommend that this change not be accepted until the platform level issue >> can be identified and corrected. >> >> -- james s >> >> >> >> On 6/30/2011 4:41 PM, James Smart wrote: >>> >>> Jon, >>> >>> I must NACK this patch to the lpfc driver and recommend that all other >>> patches >>> which replace pci_find_capability(pdef, PCI_CAP_ID_EXP) with >>> "pci_is_pcie(pdev)" are NACK'd as well. >>> >>> The reason is due to an issue on PPC platforms whereby use of >>> "pdev->is_pcie" >>> and pci_is_pcie() will erroneously fail under some conditions, but >>> explicit >>> search for the capability struct via pci_find_capability() is always >>> successful. I expect this to be due a shadowing of pci config space in >>> the >>> hal/platform that isn't sufficiently built up. We detected this issue >>> while >>> testing AER/EEH, and are functional only if the pci_find_capability() >>> option >>> is used. >>> >>> -- james s >>> >>> >>> >>> On 6/27/2011 1:39 PM, Jon Mason wrote: >>>> >>>> The PCIE capability offset is saved during PCI bus walking. It will >>>> remove an unnecessary search in the PCI configuration space if this >>>> value is referenced instead of reacquiring it. Also, pci_is_pcie is a >>>> better way of determining if the device is PCIE or not (as it uses the >>>> same saved PCIE capability offset). >>>> >>>> Signed-off-by: Jon Mason<jdmason@xxxxxxxx> >>>> --- >>>> drivers/scsi/lpfc/lpfc_init.c | 2 +- >>>> 1 files changed, 1 insertions(+), 1 deletions(-) >>>> >>>> diff --git a/drivers/scsi/lpfc/lpfc_init.c >>>> b/drivers/scsi/lpfc/lpfc_init.c >>>> index 148b98d..9000ad0 100644 >>>> --- a/drivers/scsi/lpfc/lpfc_init.c >>>> +++ b/drivers/scsi/lpfc/lpfc_init.c >>>> @@ -3970,7 +3970,7 @@ lpfc_enable_pci_dev(struct lpfc_hba *phba) >>>> pci_save_state(pdev); >>>> >>>> /* PCIe EEH recovery on powerpc platforms needs fundamental reset >>>> */ >>>> - if (pci_find_capability(pdev, PCI_CAP_ID_EXP)) >>>> + if (pci_is_pcie(pdev)) >>>> pdev->needs_freset = 1; >>>> >>>> return 0; >>> >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in >>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >> > -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
