Messages in this thread | | | From | Michael Chan <> | Date | Fri, 26 Aug 2022 09:38:51 -0700 | Subject | Re: [PATCH v2] tg3: Disable tg3 device on system reboot to avoid triggering AER |
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On Fri, Aug 26, 2022 at 9:19 AM Eric Dumazet <edumazet@google.com> wrote: > > On Thu, Aug 25, 2022 at 5:25 PM Kai-Heng Feng > <kai.heng.feng@canonical.com> wrote: > > > > Commit d60cd06331a3 ("PM: ACPI: reboot: Use S5 for reboot") caused a > > reboot hang on one Dell servers so the commit was reverted. > > > > Someone managed to collect the AER log and it's caused by MSI: > > [ 148.762067] ACPI: Preparing to enter system sleep state S5 > > [ 148.794638] {1}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 5 > > [ 148.803731] {1}[Hardware Error]: event severity: recoverable > > [ 148.810191] {1}[Hardware Error]: Error 0, type: fatal > > [ 148.816088] {1}[Hardware Error]: section_type: PCIe error > > [ 148.822391] {1}[Hardware Error]: port_type: 0, PCIe end point > > [ 148.829026] {1}[Hardware Error]: version: 3.0 > > [ 148.834266] {1}[Hardware Error]: command: 0x0006, status: 0x0010 > > [ 148.841140] {1}[Hardware Error]: device_id: 0000:04:00.0 > > [ 148.847309] {1}[Hardware Error]: slot: 0 > > [ 148.852077] {1}[Hardware Error]: secondary_bus: 0x00 > > [ 148.857876] {1}[Hardware Error]: vendor_id: 0x14e4, device_id: 0x165f > > [ 148.865145] {1}[Hardware Error]: class_code: 020000 > > [ 148.870845] {1}[Hardware Error]: aer_uncor_status: 0x00100000, aer_uncor_mask: 0x00010000 > > [ 148.879842] {1}[Hardware Error]: aer_uncor_severity: 0x000ef030 > > [ 148.886575] {1}[Hardware Error]: TLP Header: 40000001 0000030f 90028090 00000000 > > [ 148.894823] tg3 0000:04:00.0: AER: aer_status: 0x00100000, aer_mask: 0x00010000 > > [ 148.902795] tg3 0000:04:00.0: AER: [20] UnsupReq (First) > > [ 148.910234] tg3 0000:04:00.0: AER: aer_layer=Transaction Layer, aer_agent=Requester ID > > [ 148.918806] tg3 0000:04:00.0: AER: aer_uncor_severity: 0x000ef030 > > [ 148.925558] tg3 0000:04:00.0: AER: TLP Header: 40000001 0000030f 90028090 00000000 > > > > The MSI is probably raised by incoming packets, so power down the device > > and disable bus mastering to stop the traffic, as user confirmed this > > approach works. > > > > In addition to that, be extra safe and cancel reset task if it's running. > > > > Cc: Josef Bacik <josef@toxicpanda.com> > > Link: https://lore.kernel.org/all/b8db79e6857c41dab4ef08bdf826ea7c47e3bafc.1615947283.git.josef@toxicpanda.com/ > > BugLink: https://bugs.launchpad.net/bugs/1917471 > > Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com> > > --- > > v2: > > - Move tg3_reset_task_cancel() outside of rtnl_lock() to prevent > > deadlock. > > > > It seems tg3_reset_task_cancel() is already called while rtnl is held/owned. > Should we worry about that ?
In this shutdown code path, if we cancel it before rtnl_lock(), the TG3_FLAG_RESET_TASK_PENDING flag will be cleared and we will not try to cancel it again later when rtnl_lock() is held.
But I agree that calling tg3_reset_task_cancel() under rtnl_lock can potentially deadlock if the reset_task is scheduled and we wait for it to finish. That logic should be fixed separately.
> > > drivers/net/ethernet/broadcom/tg3.c | 8 ++++++-- > > 1 file changed, 6 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c > > index db1e9d810b416..89889d8150da1 100644 > > --- a/drivers/net/ethernet/broadcom/tg3.c > > +++ b/drivers/net/ethernet/broadcom/tg3.c > > @@ -18076,16 +18076,20 @@ static void tg3_shutdown(struct pci_dev *pdev) > > struct net_device *dev = pci_get_drvdata(pdev); > > struct tg3 *tp = netdev_priv(dev); > > > > + tg3_reset_task_cancel(tp); > > + > > rtnl_lock(); > > + > > netif_device_detach(dev); > > > > if (netif_running(dev)) > > dev_close(dev); > > > > - if (system_state == SYSTEM_POWER_OFF) > > - tg3_power_down(tp); > > + tg3_power_down(tp); > > > > rtnl_unlock(); > > + > > + pci_disable_device(pdev); > > } > > > > /** > > -- > > 2.36.1 > > [unhandled content-type:application/pkcs7-signature] | |