> -----Original Message----- > From: Vitaly Kuznetsov [mailto:vkuznets@xxxxxxxxxx] > Sent: Friday, April 29, 2016 2:39 AM > To: linux-pci@xxxxxxxxxxxxxxx > Cc: devel@xxxxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; KY > Srinivasan <kys@xxxxxxxxxxxxx>; Haiyang Zhang > <haiyangz@xxxxxxxxxxxxx>; Bjorn Helgaas <bhelgaas@xxxxxxxxxx>; Jake > Oshins <jakeo@xxxxxxxxxxxxx> > Subject: [PATCH] PCI: hv: report resources release after stopping the bus > > Kernel hang is observed when pci-hyperv module is release with device > drivers still attached. E.g. when I do 'rmmod pci_hyperv' with BCM5720 > device pass-through-ed (tg3 module) I see the following: > > NMI watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [rmmod:2104] > ... > Call Trace: > [<ffffffffa0641487>] tg3_read_mem+0x87/0x100 [tg3] > [<ffffffffa063f000>] ? 0xffffffffa063f000 > [<ffffffffa0644375>] tg3_poll_fw+0x85/0x150 [tg3] > [<ffffffffa0649877>] tg3_chip_reset+0x357/0x8c0 [tg3] > [<ffffffffa064ca8b>] tg3_halt+0x3b/0x190 [tg3] > [<ffffffffa0657611>] tg3_stop+0x171/0x230 [tg3] > ... > [<ffffffffa064c550>] tg3_remove_one+0x90/0x140 [tg3] > [<ffffffff813bee59>] pci_device_remove+0x39/0xc0 > [<ffffffff814a3201>] __device_release_driver+0xa1/0x160 > [<ffffffff814a32e3>] device_release_driver+0x23/0x30 > [<ffffffff813b794a>] pci_stop_bus_device+0x8a/0xa0 > [<ffffffff813b7ab6>] pci_stop_root_bus+0x36/0x60 > [<ffffffffa02c3f38>] hv_pci_remove+0x238/0x260 [pci_hyperv] > > The problem seems to be that we report local resources release before > stopping the bus and removing devices from it and device drivers may > try to perform some operations with these resources on shutdown. Move > resources release report after we do pci_stop_root_bus(). > > Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> Acked-by: Jake Oshins <jakeo@xxxxxxxxxxxxx> > --- > drivers/pci/host/pci-hyperv.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c > index f2559b6..c17e792 100644 > --- a/drivers/pci/host/pci-hyperv.c > +++ b/drivers/pci/host/pci-hyperv.c > @@ -2268,11 +2268,6 @@ static int hv_pci_remove(struct hv_device *hdev) > > hbus = hv_get_drvdata(hdev); > > - ret = hv_send_resources_released(hdev); > - if (ret) > - dev_err(&hdev->device, > - "Couldn't send resources released packet(s)\n"); > - > memset(&pkt.teardown_packet, 0, sizeof(pkt.teardown_packet)); > init_completion(&comp_pkt.host_event); > pkt.teardown_packet.completion_func = hv_pci_generic_compl; > @@ -2295,6 +2290,11 @@ static int hv_pci_remove(struct hv_device *hdev) > pci_unlock_rescan_remove(); > } > > + ret = hv_send_resources_released(hdev); > + if (ret) > + dev_err(&hdev->device, > + "Couldn't send resources released packet(s)\n"); > + > vmbus_close(hdev->channel); > > /* Delete any children which might still exist. */ > -- > 2.5.5 This looks like the right fix to me. Thanks. -- Jake Oshins -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
