On Mon, Apr 1, 2013 at 2:42 AM, Yijing Wang <wangyijing@xxxxxxxxxx> wrote: > In IA64 platform, we don't call pci_enable_bridges() > when scan all pci buses during system boot up. But in > X86 we do it in > > pcibios_assign_resources() > pci_assign_unassigned_resources() > ........... > pci_enable_bridges() > > Then when we doing hot remove > > acpiphp_disable_slot() > pci_stop_and_remove_bus_device() > pci_stop_bus_device() > ............. > pcie_portdrv_remove() > pcie_port_device_remove() > pci_disable_device() first decrease enable_cnt here > pci_disable_device() second decrease enable_cnt > So pci_dev->enable_cnt is unbalanced in IA64. > > Following Warning info found under IA64 when doing pci hotplug. > > ------------[ cut here ]------------ > WARNING: at drivers/pci/pci.c:1397 pci_disable_device+0x1c0/0x220() > Hardware name: MH8900 > Device pcieport > disabling already-disabled device > Modules linked in: acpiphp ipv6 ipmi_si(+) ipmi_devintf ipmi_msghandler fuse vfaa > t fat dm_mod iTCO_wdt iTCO_vendor_support lpc_ich i2c_i801 mfd_core i2c_core sg > sd_mod crc_t10dif ext3 mbcache jbd ata_piix > > Call Trace: > [<a000000100015c00>] show_stack+0x80/0xa0 > sp=e000000fd629fc00 bsp=e000000fd62996e0 > [<a000000100a9ca20>] dump_stack+0x30/0x50 > sp=e000000fd629fdd0 bsp=e000000fd62996c8 > [<a000000100061960>] warn_slowpath_common+0xc0/0x100 > sp=e000000fd629fdd0 bsp=e000000fd6299688 > [<a000000100061b50>] warn_slowpath_fmt+0x90/0xc0 > sp=e000000fd629fdd0 bsp=e000000fd6299628 > [<a000000100495be0>] pci_disable_device+0x1c0/0x220 > sp=e000000fd629fe10 bsp=e000000fd62995e8 > [<a0000001004b3ba0>] pcie_portdrv_remove+0xc0/0xe0 > sp=e000000fd629fe10 bsp=e000000fd62995c8 > [<a000000100499670>] pci_device_remove+0x90/0x1e0 > sp=e000000fd629fe10 bsp=e000000fd6299598 > [<a000000100636490>] __device_release_driver+0x150/0x280 > sp=e000000fd629fe10 bsp=e000000fd6299560 > [<a000000100636830>] device_release_driver+0x30/0x60 > sp=e000000fd629fe10 bsp=e000000fd6299538 > [<a000000100634a40>] bus_remove_device+0x2c0/0x3c0 > sp=e000000fd629fe10 bsp=e000000fd62994f0 > [<a0000001006306d0>] device_del+0x290/0x440 > sp=e000000fd629fe10 bsp=e000000fd62994a8 > [<a00000010048d550>] pci_stop_bus_device+0x150/0x200 > sp=e000000fd629fe10 bsp=e000000fd6299478 > [<a00000010048d470>] pci_stop_bus_device+0x70/0x200 > sp=e000000fd629fe10 bsp=e000000fd6299448 > [<a00000010048d470>] pci_stop_bus_device+0x70/0x200 > sp=e000000fd629fe10 bsp=e000000fd6299418 > [<a00000010048d9a0>] pci_stop_and_remove_bus_device+0x20/0x60 > sp=e000000fd629fe10 bsp=e000000fd62993f0 > [<a0000002089aa100>] acpiphp_disable_slot+0x240/0x4e0 [acpiphp] > sp=e000000fd629fe10 bsp=e000000fd62993a0 > [<a0000002089a8a30>] disable_slot+0x50/0x160 [acpiphp] > sp=e000000fd629fe20 bsp=e000000fd6299378 > [<a0000001004ba080>] power_write_file+0x140/0x2a0 > sp=e000000fd629fe20 bsp=e000000fd6299348 > [<a0000001004a6320>] pci_slot_attr_store+0x60/0xa0 > sp=e000000fd629fe20 bsp=e000000fd6299310 > [<a00000010032a100>] sysfs_write_file+0x240/0x340 > sp=e000000fd629fe20 bsp=e000000fd62992b8 > [<a00000010023c910>] vfs_write+0x1b0/0x3a0 > sp=e000000fd629fe20 bsp=e000000fd6299270 > [<a00000010023cc90>] sys_write+0x90/0xe0 > sp=e000000fd629fe20 bsp=e000000fd62991f0 > [<a00000010000bce0>] ia64_ret_from_syscall+0x0/0x20 > sp=e000000fd629fe30 bsp=e000000fd62991f0 > [<a000000000040720>] __kernel_syscall_via_break+0x0/0x20 > sp=e000000fd62a0000 bsp=e000000fd62991f0 > ---[ end trace 34d87c78dbff78ce ]--- > GSI 37 (level, low) -> CPU 15 (0x01e0) vector 68 unregistered > pcie_pme 0000:00:07.0:pcie01: unloading service driver pcie_pme > aer 0000:00:07.0:pcie02: unloading service driver aer > > Signed-off-by: Yijing Wang <wangyijing@xxxxxxxxxx> > Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx> > Cc: Yinghai Lu <yinghai@xxxxxxxxxx> > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > Cc: Thierry Reding <thierry.reding@xxxxxxxxxxxxxxxxx> > Cc: "Rafael J. Wysocki" <rafael.j.wysocki@xxxxxxxxx> > --- > arch/ia64/pci/pci.c | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c > index 60532ab..a557096 100644 > --- a/arch/ia64/pci/pci.c > +++ b/arch/ia64/pci/pci.c > @@ -383,6 +383,7 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) > } > > pci_scan_child_bus(pbus); > + pci_enable_bridges(pbus); > return pbus; > > out3: I think that with this patch, if you hot-add a PCI host bridge, you will call pci_enable_bridges() twice (once in pci_acpi_scan_root() and again in acpi_pci_root_add()), so there will be an enable_cnt error in the opposite direction. I'd like to see the pci_enable_bridges() calls pushed up into the generic code because I don't think there's anything arch-specific about it. Bjorn -- 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
