On 21/07/2021 18:37, Michael S. Tsirkin wrote: > On Wed, Jul 21, 2021 at 06:27:33PM +0200, Igor Mammedov wrote: >> On Wed, 21 Jul 2021 12:09:01 -0400 >> "Michael S. Tsirkin" <[email protected]> wrote: >> >>> On Wed, Jul 21, 2021 at 05:49:16PM +0200, Laurent Vivier wrote: >>>> On 21/07/2021 16:59, Igor Mammedov wrote: >>>>> On Tue, 20 Jul 2021 14:56:06 +0200 >>>>> Laurent Vivier <[email protected]> wrote: >>>>> >>>>>> On 20/07/2021 13:38, Laurent Vivier wrote: >>>>>>> On 16/07/2021 17:15, Michael S. Tsirkin wrote: >>>>>>>> From: Julia Suvorova <[email protected]> >>>>>>>> >>>>>>>> Q35 has three different types of PCI devices hot-plug: PCIe Native, >>>>>>>> SHPC Native and ACPI hot-plug. This patch changes the default choice >>>>>>>> for cold-plugged bridges from PCIe Native to ACPI Hot-plug with >>>>>>>> ability to use SHPC and PCIe Native for hot-plugged bridges. >>>>>>>> >>>>>>>> This is a list of the PCIe Native hot-plug issues that led to this >>>>>>>> change: >>>>>>>> * no racy behavior during boot (see 110c477c2ed) >>>>>>>> * no delay during deleting - after the actual power off software >>>>>>>> must wait at least 1 second before indicating about it. This case >>>>>>>> is quite important for users, it even has its own bug: >>>>>>>> https://bugzilla.redhat.com/show_bug.cgi?id=1594168 >>>>>>>> * no timer-based behavior - in addition to the previous example, >>>>>>>> the attention button has a 5-second waiting period, during which >>>>>>>> the operation can be canceled with a second press. While this >>>>>>>> looks fine for manual button control, automation will result in >>>>>>>> the need to queue or drop events, and the software receiving >>>>>>>> events in all sort of unspecified combinations of attention/power >>>>>>>> indicator states, which is racy and uppredictable. >>>>>>>> * fixes: >>>>>>>> * https://bugzilla.redhat.com/show_bug.cgi?id=1752465 >>>>>>>> * https://bugzilla.redhat.com/show_bug.cgi?id=1690256 >>>>>>>> >>>>>>>> To return to PCIe Native hot-plug: >>>>>>>> -global ICH9-LPC.acpi-pci-hotplug-with-bridge-support=off >>>>>>>> >>>>>>>> Known issue: older linux guests need the following flag >>>>>>>> to allow hotplugged pci express devices to use io: >>>>>>>> -device pcie-root-port,io-reserve=4096. >>>>>>>> io is unusual for pci express so this seems minor. >>>>>>>> We'll fix this by a follow up patch. >>>>>>>> >>>>>>>> Signed-off-by: Julia Suvorova <[email protected]> >>>>>>>> Reviewed-by: Igor Mammedov <[email protected]> >>>>>>>> Message-Id: <[email protected]> >>>>>>>> Reviewed-by: Michael S. Tsirkin <[email protected]> >>>>>>>> Signed-off-by: Michael S. Tsirkin <[email protected]> >>>>>>>> Reviewed-by: David Gibson <[email protected]> >>>>>>>> --- >>>>>>>> hw/acpi/ich9.c | 2 +- >>>>>>>> hw/i386/pc.c | 1 + >>>>>>>> 2 files changed, 2 insertions(+), 1 deletion(-) >>>>>>>> >>>>>>>> diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c >>>>>>>> index 2f4eb453ac..778e27b659 100644 >>>>>>>> --- a/hw/acpi/ich9.c >>>>>>>> +++ b/hw/acpi/ich9.c >>>>>>>> @@ -427,7 +427,7 @@ void ich9_pm_add_properties(Object *obj, >>>>>>>> ICH9LPCPMRegs *pm) >>>>>>>> pm->disable_s3 = 0; >>>>>>>> pm->disable_s4 = 0; >>>>>>>> pm->s4_val = 2; >>>>>>>> - pm->use_acpi_hotplug_bridge = false; >>>>>>>> + pm->use_acpi_hotplug_bridge = true; >>>>>>>> >>>>>>>> object_property_add_uint32_ptr(obj, ACPI_PM_PROP_PM_IO_BASE, >>>>>>>> &pm->pm_io_base, >>>>>>>> OBJ_PROP_FLAG_READ); >>>>>>>> diff --git a/hw/i386/pc.c b/hw/i386/pc.c >>>>>>>> index aa79c5e0e6..f4c7a78362 100644 >>>>>>>> --- a/hw/i386/pc.c >>>>>>>> +++ b/hw/i386/pc.c >>>>>>>> @@ -99,6 +99,7 @@ GlobalProperty pc_compat_6_0[] = { >>>>>>>> { "qemu64" "-" TYPE_X86_CPU, "model", "6" }, >>>>>>>> { "qemu64" "-" TYPE_X86_CPU, "stepping", "3" }, >>>>>>>> { TYPE_X86_CPU, "x-vendor-cpuid-only", "off" }, >>>>>>>> + { "ICH9-LPC", "acpi-pci-hotplug-with-bridge-support", "off" }, >>>>>>>> }; >>>>>>>> const size_t pc_compat_6_0_len = G_N_ELEMENTS(pc_compat_6_0); >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> There is an issue with this patch. >>>>>>> >>>>>>> When I try to unplug a VFIO device I have the following error and the >>>>>>> device is not unplugged: >>>>>>> >>>>>>> (qemu) device_del hostdev0 >>>>>>> >>>>>>> [ 34.116714] ACPI BIOS Error (bug): Could not resolve symbol >>>>>>> [^S0B.PCNT], AE_NOT_FOUND >>>>>>> (20201113/psargs-330) >>>>>>> [ 34.117987] ACPI Error: Aborting method \_SB.PCI0.PCNT due to >>>>>>> previous error >>>>>>> (AE_NOT_FOUND) (20201113/psparse-531) >>>>>>> [ 34.119318] ACPI Error: Aborting method \_GPE._E01 due to previous >>>>>>> error (AE_NOT_FOUND) >>>>>>> (20201113/psparse-531) >>>>>>> [ 34.120600] ACPI Error: AE_NOT_FOUND, while evaluating GPE method >>>>>>> [_E01] >>>>>>> (20201113/evgpe-515) >>>>>>> >>>>>>> We can see device is not unplugged (03:00.0) >>>>>>> >>>>>>> # lspci -v -s 03:00.0 >>>>>>> 03:00.0 Ethernet controller: Intel Corporation Ethernet Virtual >>>>>>> Function 700 Series (rev 02) >>>>>>> Subsystem: Intel Corporation Device 0000 >>>>>>> Flags: bus master, fast devsel, latency 0 >>>>>>> Memory at fe800000 (64-bit, prefetchable) [size=64K] >>>>>>> Memory at fe810000 (64-bit, prefetchable) [size=16K] >>>>>>> Capabilities: [70] MSI-X: Enable+ Count=5 Masked- >>>>>>> Capabilities: [a0] Express Endpoint, MSI 00 >>>>>>> Capabilities: [100] Advanced Error Reporting >>>>>>> Capabilities: [1a0] Transaction Processing Hints >>>>>>> Capabilities: [1d0] Access Control Services >>>>>>> Kernel driver in use: iavf >>>>>>> Kernel modules: iavf >>>>>>> >>>>>>> My guest kernel is from RHEL 8.5 (4.18.0-310.el8.x86_64) and my command >>>>>>> line is: >>>>>>> >>>>>>> $QEMU \ >>>>>>> -L .../pc-bios \ >>>>>>> -nodefaults \ >>>>>>> -nographic \ >>>>>>> -machine q35 \ >>>>>>> -device >>>>>>> pcie-root-port,id=pcie-root-port-0,multifunction=on,bus=pcie.0,addr=0x1,chassis=1 >>>>>>> \ >>>>>>> -device >>>>>>> pcie-pci-bridge,id=pcie-pci-bridge-0,addr=0x0,bus=pcie-root-port-0 \ >>>>>>> -device >>>>>>> pcie-root-port,id=pcie-root-port-1,port=0x1,addr=0x1.0x1,bus=pcie.0,chassis=2 >>>>>>> \ >>>>>>> -device >>>>>>> pcie-root-port,id=pcie-root-port-2,port=0x2,addr=0x1.0x2,bus=pcie.0,chassis=3 >>>>>>> \ >>>>>>> -device >>>>>>> pcie-root-port,id=pcie-root-port-3,port=0x3,addr=0x1.0x3,bus=pcie.0,chassis=4 >>>>>>> \ >>>>>>> -device >>>>>>> pcie-root-port,id=pcie_extra_root_port_0,multifunction=on,bus=pcie.0,addr=0x3,chassis=5 >>>>>>> \ >>>>>>> -nodefaults \ >>>>>>> -m 4066 \ >>>>>>> -smp 4 \ >>>>>>> -device >>>>>>> virtio-scsi-pci,id=virtio_scsi_pci0,bus=pcie-root-port-2,addr=0x0 \ >>>>>>> -blockdev >>>>>>> node-name=file_image1,driver=file,auto-read-only=on,discard=unmap,aio=threads,filename=$IMAGE,cache.direct=on,cache.no-fl\ >>>>>>> -blockdev >>>>>>> node-name=drive_image1,driver=qcow2,read-only=off,cache.direct=on,cache.no-flush=off,file=file_image1 >>>>>>> \ >>>>>>> -device scsi-hd,id=image1,drive=drive_image1,write-cache=on \ >>>>>>> -enable-kvm \ >>>>>>> -serial mon:stdio \ >>>>>>> -device vfio-pci,host=04:02.0,bus=pcie-root-port-1,addr=0x0,id=hostdev0 >>>>>>> >>>>>>> PCI 04:02.0 is: >>>>>>> >>>>>>> $ lspci -v -s 04:02.0 >>>>>>> 04:02.0 Ethernet controller: Intel Corporation Ethernet Virtual >>>>>>> Function 700 Series (rev 02) >>>>>>> Subsystem: Intel Corporation Device 0000 >>>>>>> Flags: fast devsel, NUMA node 0, IOMMU group 53 >>>>>>> Memory at 92400000 (64-bit, prefetchable) [virtual] [size=64K] >>>>>>> Memory at 92910000 (64-bit, prefetchable) [virtual] [size=16K] >>>>>>> Capabilities: <access denied> >>>>>>> Kernel driver in use: vfio-pci >>>>>>> Kernel modules: iavf >>>>>>> >>>>>>> Any idea? >>>>>> >>>>>> It also happens with non-VFIO device like e1000e: >>>>>> >>>>>> ... >>>>>> -device e1000e,bus=pcie-root-port-1,addr=0x0,id=hostdev0 \ >>>>> ^^^^^^^^^^^^^ >>>>> ACPI hotplug operates on slot level, so functions greater than 0 are not >>>>> considered, >>>>> hence unexpected ACPI error. For above CLI, setting 'addr' on root-ports >>>>> to dedicated slots >>>>> should fix issue. >>>>> >>>> >>>> Thank you for your answer. >>>> >>>> It works well with something like this: >>>> >>>> ... >>>> -device pcie-root-port,id=pcie-root-port-0,addr=0x1,bus=pcie.0,chassis=1 \ >>>> -device pcie-root-port,id=pcie-root-port-1,addr=0x2,bus=pcie.0,chassis=2 \ >>>> -device pcie-root-port,id=pcie-root-port-2,addr=0x3,bus=pcie.0,chassis=3 \ >>>> -device pcie-root-port,id=pcie-root-port-3,addr=0x4,bus=pcie.0,chassis=4 \ >>>> -device e1000e,mac=52:54:00:12:34:56,id=hostdev0,bus=pcie-root-port-1 \ >>>> ... >>>> >>>> Is this what you meant? >> yep >> >>>> >>>> On an other hand, the previous configuration worked well before this >>>> patch, can we see >>>> that as a regression? >> >> Maybe for 6.1 we should flip default back to native (revert 17858a16950860), >> until we sort out multifunction issues. > > Revert had advantages and disadvantages as usual. Let's see what the fix > is, then we can decide.
This patch breaks also virtio-net failover when the migration is canceled: the unplugged card is not plugged back. Thanks, Laurent
