lkml.org 
[lkml]   [2013]   [Feb]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    SubjectRe: [3.8-rc7] PCI hotplug wakeup oops
    Date
    On Monday, February 11, 2013 08:27:49 PM Rafael J. Wysocki wrote:
    > On Monday, February 11, 2013 12:01:37 PM Bjorn Helgaas wrote:
    > > [+cc Rafael]
    > >
    > > On Mon, Feb 11, 2013 at 10:08 AM, Daniel J Blueman <daniel@quora.org> wrote:
    > > > On 11 February 2013 21:03, Daniel J Blueman <daniel@quora.org> wrote:
    > > >> With 3.8-rc7, when unplugging the Thunderbolt ethernet adapter (bus 0a
    > > >> [1]) on a Macbook Pro 10,1, we see the PCIe port correctly released:
    > > >>
    > > >> pciehp 0000:06:03.0:pcie24: Card not present on Slot(3)
    > > >> tg3 0000:0a:00.0: tg3_abort_hw timed out, TX_MODE_ENABLE will not
    > > >> clear MAC_TX_MODE=ffffffff
    > > >> tg3 0000:0a:00.0 eth0: No firmware running
    > > >> tg3 0000:0a:00.0 eth0: Link is down
    > > >> [sched_delayed] sched: RT throttling activated
    > > >> pcieport 0000:00:01.1: System wakeup enabled by ACPI
    > > >> pciehp 0000:09:00.0:pcie24: unloading service driver pciehp
    > > >> pci_bus 0000:0a: busn_res: [bus 0a] is released
    > > >> pci_bus 0000:09: busn_res: [bus 09-0a] is released
    > > >>
    > > >> After some activity later (eg I can reproduce this by switching to a
    > > >> text console and back), often we'll see an oops:
    > > >>
    > > >> Unable to handle kernel paging request at 0000000000001070
    > > >> pci_pme_list_scan+0x3d/0xe0
    > > >> Call Trace:
    > > >> process_one_work+0x193
    > > >> ? process_one_work+0x131
    > > >> ? pci_pme_wakeup+0x60
    > > >> worker_thread+0x15d
    > > >>
    > > >> (gdb) list *(pci_pme_list_scan+0x3d)
    > > >> 0xffffffff8123f6dd is in pci_pme_list_scan (drivers/pci/pci.c:1556).
    > > >> 1551 /*
    > > >> 1552 * If bridge is in low power state, the
    > > >> 1553 * configuration space of subordinate devices
    > > >> 1554 * may be not accessible
    > > >> 1555 */
    > > >> 1556 if (bridge && bridge->current_state != PCI_D0)
    > > >> 1557 continue;
    > > >> 1558 pci_pme_wakeup(pme_dev->dev, NULL);
    > > >> 1559 } else {
    > > >> 1560 list_del(&pme_dev->list);
    > > >>
    > > >> Since a panic in vsnprintf happens after the oops (hence I can't catch
    > > >> it with EFI pstore), it is almost certainly significant heap
    > > >> corruption; this would explain why pme_dev became null (the load has
    > > >> been ordered ahead).
    > > >>
    > > >> I'll see what I can find out with memory poisoning and list debugging.
    > > >
    > > > Enabling a bunch of related debugging, we see pme_dev is non-null and:
    > > >
    > > > BUG: Unable to handle NULL pointer dereference at
    > > > pci_bus_read_config_word+0x6c
    > > > PGD 26314c067 PUD 2633f9067 PMD 0
    > > > Oops: 0000 [#1] SMP
    > > > pci_check_pme_status+0x4f
    > > > pci_pme_wakeup+0x21
    > > > pci_pme_list_scan+0xd5
    > > > process_one_work+0x1ca
    > > > ? process_one_work+0x160
    > > > ? pci_pme_wakeup+0x60
    > > > worker_thread+0x14e
    > > >
    > > > Anyway, it looks like the device being unplugged wasn't removed from
    > > > pci_pme_list as pci_pme_active(dev, false) wasn't called.
    > > >
    > > > From a quick review, I wasn't able to find the right place in the
    > > > call-chain which I only see releases the child busses and PCIe port
    > > > drivers. Anyone?
    > >
    > > It looks like drivers *add* devices to pci_pme_list when they use
    > > pci_enable_wake() or pci_wake_from_d3(). But many drivers never
    > > remove their devices, and I don't see any place where the core does it
    > > either. My guess is we need to remove it in pci_stop_dev() (we
    > > already do pcie_aspm_exit_link_state() there) or somewhere similar.
    >
    > Yes, we should call pci_pme_active(dev, false) somewhere in there I think.
    > It's fine to call that even if PME was not "active" before.

    Daniel, I wonder if the patch below helps?

    Rafael


    Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
    ---
    drivers/pci/remove.c | 2 ++
    1 file changed, 2 insertions(+)

    Index: test/drivers/pci/remove.c
    ===================================================================
    --- test.orig/drivers/pci/remove.c
    +++ test/drivers/pci/remove.c
    @@ -19,6 +19,8 @@ static void pci_free_resources(struct pc

    static void pci_stop_dev(struct pci_dev *dev)
    {
    + pci_pme_active(dev, false);
    +
    if (dev->is_added) {
    pci_proc_detach_device(dev);
    pci_remove_sysfs_dev_files(dev);


    --
    I speak only for myself.
    Rafael J. Wysocki, Intel Open Source Technology Center.


    \
     
     \ /
      Last update: 2013-02-11 21:21    [W:3.887 / U:0.012 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site