Bug 43219
| Summary: | Fail to hot-remove multiple function devices in Linux VM | ||
|---|---|---|---|
| Product: | Drivers | Reporter: | Amos Kong (kongjianjun) |
| Component: | PCI | Assignee: | Amos Kong (kongjianjun) |
| Status: | RESOLVED CODE_FIX | ||
| Severity: | normal | CC: | alan, florian, jbarnes |
| Priority: | P1 | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Kernel Version: | 3.3.0 | Subsystem: | |
| Regression: | No | Bisected commit-id: | |
| Attachments: |
Dmesg -- acpiphp register
seabios ACPI DSDT (acpi-dsdt.dsl.i ssdt-pcihp.dsl.i) |
||
Created attachment 73229 [details]
seabios ACPI DSDT (acpi-dsdt.dsl.i ssdt-pcihp.dsl.i)
Posted patch to linux-pci maillist [PATCH v2] pci: clean all funcs when hot-removing multifunc device http://marc.info/?l=linux-pci&m=133657729118731&w=2
>>> Hotplug CallTrace:
int acpiphp_enable_slot(struct acpiphp_slot *slot)
\_enable_device(slot);
\_pci_bus_add_devices(bus); // all un-added new devs will be added
list_for_each_entry(dev, &bus->devices, bus_list) {
if (dev->is_added)
continue;
pci_bus_add_device(dev);
device_add(&dev->dev);
dev->is_added = 1;
'dev->is_added' is used to track if pci dev is added to bus, all funcs in
same slot would be added to bus in enable_device(slot). So we need to clean
all funcs of same slot in disable_device(slot).
A patch referencing this bug report has been merged in Linux v3.6-rc1: commit ce29ca3ea40744f24c2b5d88431e8ac566d257cc Author: Amos Kong <kongjianjun@gmail.com> Date: Wed May 23 10:20:35 2012 -0600 PCI: acpiphp: remove all functions in slot, even without ACPI _EJx |
Created attachment 73228 [details] Dmesg -- acpiphp register Boot up a Linux VM with 8 pci block devices which are the 8 functions in one pci slot. | # qemu-kvm ... | -drive file=images/u0,if=none,id=drv0,format=qcow2,cache=none \ | -device virtio-blk-pci,drive=drv0,id=v0,multifunction=on,addr=0x03.0 \ | .... | -drive file=images/u7,if=none,id=drv7,format=qcow2,cache=none \ | -device virtio-blk-pci,drive=drv7,id=v7,multifunction=on,addr=0x03.7 \ Check devices in guest. | vm)# ls /dev/vd* | vda vdb vdc vde vdf vdg vdh | vm)# lspci |grep block | 00:03.0 SCSI storage controller: Red Hat, Inc Virtio block device | ... | 00:03.7 SCSI storage controller: Red Hat, Inc Virtio block device | Func1~7 still exist in guest after hot-removing the whole slot through qemu monitor. | vm)# lspci |grep block (00:03.0 disappeared) | 00:03.1 SCSI storage controller: Red Hat, Inc Virtio block device (rev ff) | ... | 00:03.7 SCSI storage controller: Red Hat, Inc Virtio block device (rev ff) | vm)# ls /dev/vd* (vda disappeared) | vdb vdc vde vdf vdg vdh | vm)# mkfs /dev/vdb | INFO: task mkfs.ext2:1784 blocked for more than 120 seconds. expected result: all functions are removed in guest