On Wed, 21 Jul 2021 12:09:01 -0400 "Michael S. Tsirkin" <m...@redhat.com> 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 <lviv...@redhat.com> wrote: > > > > > >> On 20/07/2021 13:38, Laurent Vivier wrote: > > >>> On 16/07/2021 17:15, Michael S. Tsirkin wrote: > > >>>> From: Julia Suvorova <jus...@redhat.com> > > >>>> > > >>>> 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 <jus...@redhat.com> > > >>>> Reviewed-by: Igor Mammedov <imamm...@redhat.com> > > >>>> Message-Id: <20210713004205.775386-6-jus...@redhat.com> > > >>>> Reviewed-by: Michael S. Tsirkin <m...@redhat.com> > > >>>> Signed-off-by: Michael S. Tsirkin <m...@redhat.com> > > >>>> Reviewed-by: David Gibson <da...@gibson.dropbear.id.au> > > >>>> --- > > >>>> 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. > > > > Thanks, > > Laurent > > > I agree, port itself can be multifunction, slot behind it is a single > function. Looks like a bug to me. Julia? I quickly cobbled up acpi hack to do it. But kernel refuses to see bridges described in ACPI other than on function 0. I'll play with it tomorrow some more. PS: (it's a bit more than I'm comfortable to push as a fix for 6.1 anyways)
