James Bottomley wrote: > On Mon, 2009-01-19 at 10:10 +0900, Kenji Kaneshige wrote: >> James Bottomley wrote: >>> On Fri, 2009-01-16 at 15:07 +0900, Kenji Kaneshige wrote: >>>>> It looks like acpi_pci_get_bridge_handle() is returning NULL, so this is >>>>> the fix that works for me. >>>>> >>>> I'm sorry for troubling you, and thank you for your patience. >>>> >>>> The patch seems to avoid the kernel panic, but I still don't know >>>> why acpi_pci_get_bridge_handle() returns NULL here. I assumed >>>> it should return non-NULL value here. So I'd like to investigate >>>> it more. >>> Sure, Len and I couldn't work out why it was returning NULL on this box >>> (other than that perhaps it doesn't have an ACPI entry). The two >>> offending busses which trigger this are the two internal ones (which >>> aren't hotplug). The layout of the box is: >>> >>> sparkweed:~# lspci -t >>> -+-[0000:0c]---00.0 >>> +-[0000:0a]---00.0 >>> +-[0000:08]---00.0 >>> +-[0000:06]---00.0 >>> +-[0000:04]---00.0 >>> +-[0000:02]---00.0 >>> +-[0000:01]-+-00.0 >>> | +-01.0 >>> | +-01.1 >>> | \-02.0 >>> \-[0000:00]-+-00.0 >>> +-01.0 >>> +-03.0 >>> +-03.1 >>> +-03.2 >>> +-0f.0 >>> +-0f.1 >>> \-0f.3 >>> sparkweed:~# lspci >>> 00:00.0 Host bridge: IBM Calgary PCI-X Host Bridge (rev 02) >>> 00:01.0 VGA compatible controller: ATI Technologies Inc Radeon RV100 QY >>> [Radeon 7000/VE] >>> 00:03.0 USB Controller: NEC Corporation USB (rev 43) >>> 00:03.1 USB Controller: NEC Corporation USB (rev 43) >>> 00:03.2 USB Controller: NEC Corporation USB 2.0 (rev 04) >>> 00:0f.0 Host bridge: Broadcom CSB6 South Bridge (rev a0) >>> 00:0f.1 IDE interface: Broadcom CSB6 RAID/IDE Controller (rev a0) >>> 00:0f.3 ISA bridge: Broadcom GCLE-2 Host Bridge >>> 01:00.0 Host bridge: IBM Calgary PCI-X Host Bridge (rev 02) >>> 01:01.0 Ethernet controller: Broadcom Corporation NetXtreme BCM5704 >>> Gigabit Ethernet (rev 10) >>> 01:01.1 Ethernet controller: Broadcom Corporation NetXtreme BCM5704 >>> Gigabit Ethernet (rev 10) >>> 01:02.0 SCSI storage controller: Adaptec AIC-9410W SAS (Razor ASIC >>> non-RAID) (rev 08) >>> 02:00.0 Host bridge: IBM Calgary PCI-X Host Bridge (rev 02) >>> 04:00.0 Host bridge: IBM Calgary PCI-X Host Bridge (rev 02) >>> 06:00.0 Host bridge: IBM Calgary PCI-X Host Bridge (rev 02) >>> 08:00.0 Host bridge: IBM Calgary PCI-X Host Bridge (rev 02) >>> 0a:00.0 Host bridge: IBM Calgary PCI-X Host Bridge (rev 02) >>> 0c:00.0 Host bridge: IBM Calgary PCI-X Host Bridge (rev 02) >>> >>> And when I annotate the problem, the two busses returning NULL are >>> 0000:00 and 0000:01 >>> >> Thank you very much for the information. It seems there are >> something special in the data structure of host bridge for >> 0000:00 and 0000:01. > > Yes, len speculates the non hotplug buses are missing some acpi entries. > >> I'm making a debug patch now and will send it to you as soon >> as possible. I'm sorry to trouble you, but could you try it >> later. > > Sure ... I'm travelling this week, but the machine is usually remotely > accessible. > I appreciate your kindness. I'm sending the debug patch against 2.6.29-rc1 below. I'm also sending it as an attachment. It also contains the code to prevent the kernel panic from you. Please note that you will see two WARN_ON(1) messages with the patch. Those are shown by my debug patch. Could you try it and send me the whole dmsg output? Thanks, Kenji Kaneshige drivers/pci/hotplug/acpiphp_glue.c | 18 ++++++++++++++++++ include/linux/pci-acpi.h | 25 ++++++++++++++++++++++--- 2 files changed, 40 insertions(+), 3 deletions(-) Index: linux-2.6.29-rc1/include/linux/pci-acpi.h =================================================================== --- linux-2.6.29-rc1.orig/include/linux/pci-acpi.h 2008-12-01 22:59:52.000000000 +0900 +++ linux-2.6.29-rc1/include/linux/pci-acpi.h 2009-01-19 10:27:13.000000000 +0900 @@ -65,9 +65,28 @@ { int seg = pci_domain_nr(pbus), busnr = pbus->number; struct pci_dev *bridge = pbus->self; - if (bridge) - return DEVICE_ACPI_HANDLE(&(bridge->dev)); - return acpi_get_pci_rootbridge_handle(seg, busnr); + acpi_handle handle; + char objname[64] = "<NULL>"; + struct acpi_buffer buffer = { .length = sizeof(objname), + .pointer = objname }; + + printk(KERN_INFO "%s: bridge(pbus->self) = %p, pbus->parent = %p\n", + __func__, bridge, pbus->parent); + + if (bridge) { + printk(KERN_INFO "%s: handle the bridge as PtoP.\n", __func__); + handle = DEVICE_ACPI_HANDLE(&(bridge->dev)); + } else { + printk(KERN_INFO "%s: handle the bridge as root.\n", __func__); + handle = acpi_get_pci_rootbridge_handle(seg, busnr); + } + + if (handle) + acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); + printk(KERN_INFO "%s: ACPI handle of the bridge for %04x:%02x: %p %s\n", + __func__, seg, busnr, handle, objname); + + return handle; } #else #if !defined(AE_ERROR) Index: linux-2.6.29-rc1/drivers/pci/hotplug/acpiphp_glue.c =================================================================== --- linux-2.6.29-rc1.orig/drivers/pci/hotplug/acpiphp_glue.c 2008-12-01 22:59:46.000000000 +0900 +++ linux-2.6.29-rc1/drivers/pci/hotplug/acpiphp_glue.c 2009-01-19 10:32:05.000000000 +0900 @@ -266,6 +266,12 @@ int found = acpi_pci_detect_ejectable(pbus); if (!found) { acpi_handle bridge_handle = acpi_pci_get_bridge_handle(pbus); + if (!bridge_handle) { + printk(KERN_INFO + "%s: NULL handle returned!!!\n", __func__); + WARN_ON(1); + return 0; + } acpi_walk_namespace(ACPI_TYPE_DEVICE, bridge_handle, (u32)1, is_pci_dock_device, (void *)&found, NULL); } @@ -459,6 +465,9 @@ int device, function; struct pci_dev *dev; struct pci_bus *pci_bus = context; + char objname[64]; + struct acpi_buffer buffer = { .length = sizeof(objname), + .pointer = objname }; status = acpi_get_handle(handle, "_ADR", &dummy_handle); if (ACPI_FAILURE(status)) @@ -478,6 +487,9 @@ if (!dev || !dev->subordinate) goto out; + acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); + printk(KERN_INFO "%s: Detecting slots under PtoP bridge (%s)\n", + __func__, objname); /* check if this bridge has ejectable slots */ if ((detect_ejectable_slots(dev->subordinate) > 0)) { dbg("found PCI-to-PCI bridge at PCI %s\n", pci_name(dev)); @@ -504,6 +516,9 @@ int seg, bus; acpi_handle dummy_handle; struct pci_bus *pci_bus; + char objname[64]; + struct acpi_buffer buffer = { .length = sizeof(objname), + .pointer = objname }; /* if the bridge doesn't have _STA, we assume it is always there */ status = acpi_get_handle(handle, "_STA", &dummy_handle); @@ -539,6 +554,9 @@ return 0; } + acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); + printk(KERN_INFO "%s: Detecting slots under root bridge (%s)\n", + __func__, objname); /* check if this bridge has ejectable slots */ if (detect_ejectable_slots(pci_bus) > 0) { dbg("found PCI host-bus bridge with hot-pluggable slots\n");
drivers/pci/hotplug/acpiphp_glue.c | 18 ++++++++++++++++++ include/linux/pci-acpi.h | 25 ++++++++++++++++++++++--- 2 files changed, 40 insertions(+), 3 deletions(-) Index: linux-2.6.29-rc1/include/linux/pci-acpi.h =================================================================== --- linux-2.6.29-rc1.orig/include/linux/pci-acpi.h 2008-12-01 22:59:52.000000000 +0900 +++ linux-2.6.29-rc1/include/linux/pci-acpi.h 2009-01-19 10:27:13.000000000 +0900 @@ -65,9 +65,28 @@ { int seg = pci_domain_nr(pbus), busnr = pbus->number; struct pci_dev *bridge = pbus->self; - if (bridge) - return DEVICE_ACPI_HANDLE(&(bridge->dev)); - return acpi_get_pci_rootbridge_handle(seg, busnr); + acpi_handle handle; + char objname[64] = "<NULL>"; + struct acpi_buffer buffer = { .length = sizeof(objname), + .pointer = objname }; + + printk(KERN_INFO "%s: bridge(pbus->self) = %p, pbus->parent = %p\n", + __func__, bridge, pbus->parent); + + if (bridge) { + printk(KERN_INFO "%s: handle the bridge as PtoP.\n", __func__); + handle = DEVICE_ACPI_HANDLE(&(bridge->dev)); + } else { + printk(KERN_INFO "%s: handle the bridge as root.\n", __func__); + handle = acpi_get_pci_rootbridge_handle(seg, busnr); + } + + if (handle) + acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); + printk(KERN_INFO "%s: ACPI handle of the bridge for %04x:%02x: %p %s\n", + __func__, seg, busnr, handle, objname); + + return handle; } #else #if !defined(AE_ERROR) Index: linux-2.6.29-rc1/drivers/pci/hotplug/acpiphp_glue.c =================================================================== --- linux-2.6.29-rc1.orig/drivers/pci/hotplug/acpiphp_glue.c 2008-12-01 22:59:46.000000000 +0900 +++ linux-2.6.29-rc1/drivers/pci/hotplug/acpiphp_glue.c 2009-01-19 10:32:05.000000000 +0900 @@ -266,6 +266,12 @@ int found = acpi_pci_detect_ejectable(pbus); if (!found) { acpi_handle bridge_handle = acpi_pci_get_bridge_handle(pbus); + if (!bridge_handle) { + printk(KERN_INFO + "%s: NULL handle returned!!!\n", __func__); + WARN_ON(1); + return 0; + } acpi_walk_namespace(ACPI_TYPE_DEVICE, bridge_handle, (u32)1, is_pci_dock_device, (void *)&found, NULL); } @@ -459,6 +465,9 @@ int device, function; struct pci_dev *dev; struct pci_bus *pci_bus = context; + char objname[64]; + struct acpi_buffer buffer = { .length = sizeof(objname), + .pointer = objname }; status = acpi_get_handle(handle, "_ADR", &dummy_handle); if (ACPI_FAILURE(status)) @@ -478,6 +487,9 @@ if (!dev || !dev->subordinate) goto out; + acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); + printk(KERN_INFO "%s: Detecting slots under PtoP bridge (%s)\n", + __func__, objname); /* check if this bridge has ejectable slots */ if ((detect_ejectable_slots(dev->subordinate) > 0)) { dbg("found PCI-to-PCI bridge at PCI %s\n", pci_name(dev)); @@ -504,6 +516,9 @@ int seg, bus; acpi_handle dummy_handle; struct pci_bus *pci_bus; + char objname[64]; + struct acpi_buffer buffer = { .length = sizeof(objname), + .pointer = objname }; /* if the bridge doesn't have _STA, we assume it is always there */ status = acpi_get_handle(handle, "_STA", &dummy_handle); @@ -539,6 +554,9 @@ return 0; } + acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); + printk(KERN_INFO "%s: Detecting slots under root bridge (%s)\n", + __func__, objname); /* check if this bridge has ejectable slots */ if (detect_ejectable_slots(pci_bus) > 0) { dbg("found PCI host-bus bridge with hot-pluggable slots\n");