| Message ID | 1482216573-21487-1-git-send-email-gwshan@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On Tue, Dec 20, 2016 at 05:49:33PM +1100, Gavin Shan wrote: > The surprise hotplug is driven by interrupt in PowerNV PCI hotplug > driver. In the interrupt handler, pnv_php_interrupt(), we bail when > pnv_pci_get_presence_state() returns zero wrongly. It causes the > presence change event is always ignored incorrectly. > > This fixes the issue by bailing on error (non-zero value) returned > from pnv_pci_get_presence_state(). > > Fixes: 360aebd85a4 ("drivers/pci/hotplug: Support surprise hotplug in powernv driver") > Cc: stable@vger.kernel.org #v4.9+ > Reported-by: Hank Chang <hankmax0000@gmail.com> > Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> > Tested-by: Willie Liauw <williel@supermicro.com.tw> > --- > drivers/pci/hotplug/pnv_php.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c > index 56efaf7..38a2309 100644 > --- a/drivers/pci/hotplug/pnv_php.c > +++ b/drivers/pci/hotplug/pnv_php.c > @@ -707,8 +707,12 @@ static irqreturn_t pnv_php_interrupt(int irq, void *data) > added = !!(lsts & PCI_EXP_LNKSTA_DLLLA); > } else if (sts & PCI_EXP_SLTSTA_PDC) { > ret = pnv_pci_get_presence_state(php_slot->id, &presence); > - if (!ret) > + if (ret) { > + dev_warn(&pdev->dev, "PCI slot [%s] error %d handling PDC event (0x%04x)\n", > + php_slot->name, ret, sts); What can a user do with this warning?
On Tue, Dec 20, 2016 at 10:37:09AM +0100, Greg KH wrote: >On Tue, Dec 20, 2016 at 05:49:33PM +1100, Gavin Shan wrote: >> The surprise hotplug is driven by interrupt in PowerNV PCI hotplug >> driver. In the interrupt handler, pnv_php_interrupt(), we bail when >> pnv_pci_get_presence_state() returns zero wrongly. It causes the >> presence change event is always ignored incorrectly. >> >> This fixes the issue by bailing on error (non-zero value) returned >> from pnv_pci_get_presence_state(). >> >> Fixes: 360aebd85a4 ("drivers/pci/hotplug: Support surprise hotplug in powernv driver") >> Cc: stable@vger.kernel.org #v4.9+ >> Reported-by: Hank Chang <hankmax0000@gmail.com> >> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> >> Tested-by: Willie Liauw <williel@supermicro.com.tw> >> --- >> drivers/pci/hotplug/pnv_php.c | 6 +++++- >> 1 file changed, 5 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c >> index 56efaf7..38a2309 100644 >> --- a/drivers/pci/hotplug/pnv_php.c >> +++ b/drivers/pci/hotplug/pnv_php.c >> @@ -707,8 +707,12 @@ static irqreturn_t pnv_php_interrupt(int irq, void *data) >> added = !!(lsts & PCI_EXP_LNKSTA_DLLLA); >> } else if (sts & PCI_EXP_SLTSTA_PDC) { >> ret = pnv_pci_get_presence_state(php_slot->id, &presence); >> - if (!ret) >> + if (ret) { >> + dev_warn(&pdev->dev, "PCI slot [%s] error %d handling PDC event (0x%04x)\n", >> + php_slot->name, ret, sts); > >What can a user do with this warning? > This warning is to catch developer's attention only. It's very rare for pnv_pci_get_presence_state() to fail as it simply checks hardware regiter bit (from Slot Status regsiter in PCIe capability or PHB's Hotplug Override register) in the skiboot firmware. User needs to retry the operation (hot-add or hot-remove) when seeing this warning. Greg, please let me know if below message is better? dev_warn(&pdev->dev, "PCI slot [%s] error %d getting presence status on event 0x%04x, to retry the operation.\n", php_slot->name, ret, sts); Thanks, Gavin
On Tue, Dec 20, 2016 at 05:49:33PM +1100, Gavin Shan wrote: >The surprise hotplug is driven by interrupt in PowerNV PCI hotplug >driver. In the interrupt handler, pnv_php_interrupt(), we bail when >pnv_pci_get_presence_state() returns zero wrongly. It causes the >presence change event is always ignored incorrectly. > >This fixes the issue by bailing on error (non-zero value) returned >from pnv_pci_get_presence_state(). > >Fixes: 360aebd85a4 ("drivers/pci/hotplug: Support surprise hotplug in powernv driver") >Cc: stable@vger.kernel.org #v4.9+ >Reported-by: Hank Chang <hankmax0000@gmail.com> >Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> >Tested-by: Willie Liauw <williel@supermicro.com.tw> >--- Please ignore this one for now. I will post a revised series to fix more issues found in recent testing. Also, the warning message will be modified accordingly. Thanks, Gavin > drivers/pci/hotplug/pnv_php.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > >diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c >index 56efaf7..38a2309 100644 >--- a/drivers/pci/hotplug/pnv_php.c >+++ b/drivers/pci/hotplug/pnv_php.c >@@ -707,8 +707,12 @@ static irqreturn_t pnv_php_interrupt(int irq, void *data) > added = !!(lsts & PCI_EXP_LNKSTA_DLLLA); > } else if (sts & PCI_EXP_SLTSTA_PDC) { > ret = pnv_pci_get_presence_state(php_slot->id, &presence); >- if (!ret) >+ if (ret) { >+ dev_warn(&pdev->dev, "PCI slot [%s] error %d handling PDC event (0x%04x)\n", >+ php_slot->name, ret, sts); > return IRQ_HANDLED; >+ } >+ > added = !!(presence == OPAL_PCI_SLOT_PRESENT); > } else { > return IRQ_NONE; >-- >2.7.4 >
diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c index 56efaf7..38a2309 100644 --- a/drivers/pci/hotplug/pnv_php.c +++ b/drivers/pci/hotplug/pnv_php.c @@ -707,8 +707,12 @@ static irqreturn_t pnv_php_interrupt(int irq, void *data) added = !!(lsts & PCI_EXP_LNKSTA_DLLLA); } else if (sts & PCI_EXP_SLTSTA_PDC) { ret = pnv_pci_get_presence_state(php_slot->id, &presence); - if (!ret) + if (ret) { + dev_warn(&pdev->dev, "PCI slot [%s] error %d handling PDC event (0x%04x)\n", + php_slot->name, ret, sts); return IRQ_HANDLED; + } + added = !!(presence == OPAL_PCI_SLOT_PRESENT); } else { return IRQ_NONE;
The surprise hotplug is driven by interrupt in PowerNV PCI hotplug driver. In the interrupt handler, pnv_php_interrupt(), we bail when pnv_pci_get_presence_state() returns zero wrongly. It causes the presence change event is always ignored incorrectly. This fixes the issue by bailing on error (non-zero value) returned from pnv_pci_get_presence_state(). Fixes: 360aebd85a4 ("drivers/pci/hotplug: Support surprise hotplug in powernv driver") Cc: stable@vger.kernel.org #v4.9+ Reported-by: Hank Chang <hankmax0000@gmail.com> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Tested-by: Willie Liauw <williel@supermicro.com.tw> --- drivers/pci/hotplug/pnv_php.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)