| Message ID | 1475479872-112822-1-git-send-email-jeffrey.t.kirsher@intel.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Date: Mon, 3 Oct 2016 00:31:12 -0700 > From: Guilherme G Piccoli <gpiccoli@linux.vnet.ibm.com> > > Although rare, it's possible to hit PCI error early on device > probe, meaning possibly some structs are not entirely initialized, > and some might even be completely uninitialized, leading to NULL > pointer dereference. > > The i40e driver currently presents a "bad" behavior if device hits > such early PCI error: firstly, the struct i40e_pf might not be > attached to pci_dev yet, leading to a NULL pointer dereference on > access to pf->state. > > Even checking if the struct is NULL and avoiding the access in that > case isn't enough, since the driver cannot recover from PCI error > that early; in our experiments we saw multiple failures on kernel > log, like: > > [549.664] i40e 0007:01:00.1: Initial pf_reset failed: -15 > [549.664] i40e: probe of 0007:01:00.1 failed with error -15 > [...] > [871.644] i40e 0007:01:00.1: The driver for the device stopped because the > device firmware failed to init. Try updating your NVM image. > [871.644] i40e: probe of 0007:01:00.1 failed with error -32 > [...] > [872.516] i40e 0007:01:00.0: ARQ: Unknown event 0x0000 ignored > > Between the first probe failure (error -15) and the second (error -32) > another PCI error happened due to the first bad probe. Also, driver > started to flood console with those ARQ event messages. > > This patch will prevent these issues by allowing error recovery > mechanism to remove the failed device from the system instead of > trying to recover from early PCI errors during device probe. > > CC: <stable@vger.kernel.org> > Signed-off-by: Guilherme G Piccoli <gpiccoli@linux.vnet.ibm.com> > Acked-by: Jacob Keller <jacob.e.keller@intel.com> > Tested-by: Andrew Bowers <andrewx.bowers@intel.com> > Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Applied.
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c index 8176596..efc0a36 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_main.c +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c @@ -11382,6 +11382,12 @@ static pci_ers_result_t i40e_pci_error_detected(struct pci_dev *pdev, dev_info(&pdev->dev, "%s: error %d\n", __func__, error); + if (!pf) { + dev_info(&pdev->dev, + "Cannot recover - error happened during device probe\n"); + return PCI_ERS_RESULT_DISCONNECT; + } + /* shutdown all operations */ if (!test_bit(__I40E_SUSPENDED, &pf->state)) { rtnl_lock();