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Subject: Re: [PATCH v2 09/16] OvmfPkg/CpuHotplugSmm: add function for collecting CPUs with events
To: =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= <philmd@redhat.com>,
 edk2-devel-groups-io <devel@edk2.groups.io>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>,
 Igor Mammedov <imammedo@redhat.com>, Jiewen Yao <jiewen.yao@intel.com>,
 Jordan Justen <jordan.l.justen@intel.com>,
 Michael Kinney <michael.d.kinney@intel.com>
References: <20200226221156.29589-1-lersek@redhat.com>
 <20200226221156.29589-10-lersek@redhat.com>
 <d693f2ff-e577-24ee-252d-53d8e986149f@redhat.com>
From: "Laszlo Ersek" <lersek@redhat.com>
Message-ID: <3b172735-2b25-919a-6762-02775d334daa@redhat.com>
Date: Tue, 3 Mar 2020 11:31:40 +0100
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On 03/02/20 21:34, Philippe Mathieu-Daud=C3=A9 wrote:
> On 2/26/20 11:11 PM, Laszlo Ersek wrote:
>> Add a function that collects the APIC IDs of CPUs that have just been
>> hot-plugged, or are about to be hot-unplugged.
>>
>> Pending events are only located and never cleared; QEMU's AML needs the
>> firmware to leave the status bits intact in the hotplug register block.
>>
>> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>> Cc: Igor Mammedov <imammedo@redhat.com>
>> Cc: Jiewen Yao <jiewen.yao@intel.com>
>> Cc: Jordan Justen <jordan.l.justen@intel.com>
>> Cc: Michael Kinney <michael.d.kinney@intel.com>
>> Cc: Philippe Mathieu-Daud=C3=A9 <philmd@redhat.com>
>> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3D1512
>> Signed-off-by: Laszlo Ersek <lersek@redhat.com>
>> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>> ---
>>
>> Notes:
>> =C2=A0=C2=A0=C2=A0=C2=A0 v2:
>> =C2=A0=C2=A0=C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0 - Pick up Ard's Acked-=
by, which is conditional on approval
>> from Intel
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 reviewers on Cc. (I'd like to save =
Ard the churn of re-acking
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 unmodified patches.)
>>
>> =C2=A0 OvmfPkg/Include/IndustryStandard/QemuCpuHotplug.h |=C2=A0=C2=A0 2=
 +
>> =C2=A0 OvmfPkg/CpuHotplugSmm/CpuHotplugSmm.inf=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 |=C2=A0=C2=A0 1 +
>> =C2=A0 OvmfPkg/CpuHotplugSmm/ApicId.h=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0 |=C2=A0 23 +++
>> =C2=A0 OvmfPkg/CpuHotplugSmm/QemuCpuhp.h=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 |=C2=A0 =
20 ++-
>> =C2=A0 OvmfPkg/CpuHotplugSmm/QemuCpuhp.c=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 | 171
>> +++++++++++++++++++-
>> =C2=A0 5 files changed, 211 insertions(+), 6 deletions(-)
>>
>> diff --git a/OvmfPkg/Include/IndustryStandard/QemuCpuHotplug.h
>> b/OvmfPkg/Include/IndustryStandard/QemuCpuHotplug.h
>> index 3d013633501b..a34a6d3fae61 100644
>> --- a/OvmfPkg/Include/IndustryStandard/QemuCpuHotplug.h
>> +++ b/OvmfPkg/Include/IndustryStandard/QemuCpuHotplug.h
>> @@ -13,32 +13,34 @@
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 The new ("modern") hotplug interface appe=
ared in QEMU v2.7.0.
>> =C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 The macros in this header file map=
 to the minimal subset of
>> the modern
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 interface that OVMF needs.
>> =C2=A0 **/
>> =C2=A0 =C2=A0 #ifndef QEMU_CPU_HOTPLUG_H_
>> =C2=A0 #define QEMU_CPU_HOTPLUG_H_
>> =C2=A0 =C2=A0 #include <Base.h>
>> =C2=A0 =C2=A0 //
>> =C2=A0 // Each register offset is:
>> =C2=A0 // - relative to the board-dependent IO base address of the regis=
ter
>> block,
>> =C2=A0 // - named QEMU_CPUHP_(R|W|RW)_*, according to the possible acces=
s
>> modes of the
>> =C2=A0 //=C2=A0=C2=A0 register,
>> =C2=A0 // - followed by distinguished bitmasks or values in the register=
.
>> =C2=A0 //
>> =C2=A0 #define QEMU_CPUHP_R_CMD_DATA2=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0x0
>> =C2=A0 =C2=A0 #define QEMU_CPUHP_R_CPU_STAT=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0x4
>> =C2=A0 #define QEMU_CPUHP_STAT_ENABLED=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 BIT0
>> +#define QEMU_CPUHP_STAT_INSERT=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 BIT1
>> +#define QEMU_CPUHP_STAT_REMOVE=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 BIT2
>> =C2=A0 =C2=A0 #define QEMU_CPUHP_RW_CMD_DATA=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0x8
>> =C2=A0 =C2=A0 #define QEMU_CPUHP_W_CPU_SEL=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0x0
>> =C2=A0 =C2=A0 #define QEMU_CPUHP_W_CMD=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0 0x5
>> =C2=A0 #define QEMU_CPUHP_CMD_GET_PENDING=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0x0
>> =C2=A0 #define QEMU_CPUHP_CMD_GET_ARCH_ID=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0x3
>> =C2=A0 =C2=A0 #endif // QEMU_CPU_HOTPLUG_H_
>> diff --git a/OvmfPkg/CpuHotplugSmm/CpuHotplugSmm.inf
>> b/OvmfPkg/CpuHotplugSmm/CpuHotplugSmm.inf
>> index ac4ca4c1f4f2..ab690a9e5e20 100644
>> --- a/OvmfPkg/CpuHotplugSmm/CpuHotplugSmm.inf
>> +++ b/OvmfPkg/CpuHotplugSmm/CpuHotplugSmm.inf
>> @@ -3,44 +3,45 @@
>> =C2=A0 #
>> =C2=A0 # Copyright (c) 2020, Red Hat, Inc.
>> =C2=A0 #
>> =C2=A0 # SPDX-License-Identifier: BSD-2-Clause-Patent
>> =C2=A0 ##
>> =C2=A0 =C2=A0 [Defines]
>> =C2=A0=C2=A0=C2=A0 INF_VERSION=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 =3D 1.29
>> =C2=A0=C2=A0=C2=A0 PI_SPECIFICATION_VERSION=C2=A0=C2=A0 =3D 0x00010046=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0
>> # PI-1.7.0
>> =C2=A0=C2=A0=C2=A0 BASE_NAME=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 =3D CpuHotplug=
Smm
>> =C2=A0=C2=A0=C2=A0 FILE_GUID=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 =3D 84EEA114-C=
6BE-4445-8F90-51D97863E363
>> =C2=A0=C2=A0=C2=A0 MODULE_TYPE=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 =3D DXE_SMM_DRIVER
>> =C2=A0=C2=A0=C2=A0 ENTRY_POINT=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 =3D CpuHotplugEntry
>> =C2=A0 =C2=A0 #
>> =C2=A0 # The following information is for reference only and not require=
d
>> by the build
>> =C2=A0 # tools.
>> =C2=A0 #
>> =C2=A0 # VALID_ARCHITECTURES=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 =
=3D IA32 X64
>> =C2=A0 #
>> =C2=A0 =C2=A0 [Sources]
>> +=C2=A0 ApicId.h
>> =C2=A0=C2=A0=C2=A0 CpuHotplug.c
>> =C2=A0=C2=A0=C2=A0 QemuCpuhp.c
>> =C2=A0=C2=A0=C2=A0 QemuCpuhp.h
>> =C2=A0 =C2=A0 [Packages]
>> =C2=A0=C2=A0=C2=A0 MdePkg/MdePkg.dec
>> =C2=A0=C2=A0=C2=A0 OvmfPkg/OvmfPkg.dec
>> =C2=A0 =C2=A0 [LibraryClasses]
>> =C2=A0=C2=A0=C2=A0 BaseLib
>> =C2=A0=C2=A0=C2=A0 DebugLib
>> =C2=A0=C2=A0=C2=A0 MmServicesTableLib
>> =C2=A0=C2=A0=C2=A0 PcdLib
>> =C2=A0=C2=A0=C2=A0 UefiDriverEntryPoint
>> =C2=A0 =C2=A0 [Protocols]
>> =C2=A0=C2=A0=C2=A0 gEfiMmCpuIoProtocolGuid=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0
>> ## CONSUMES
>> =C2=A0 =C2=A0 [Pcd]
>> =C2=A0=C2=A0=C2=A0 gUefiOvmfPkgTokenSpaceGuid.PcdQ35SmramAtDefaultSmbase=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0
>> ## CONSUMES
>> =C2=A0 =C2=A0 [FeaturePcd]
>> diff --git a/OvmfPkg/CpuHotplugSmm/ApicId.h
>> b/OvmfPkg/CpuHotplugSmm/ApicId.h
>> new file mode 100644
>> index 000000000000..3c365148ed02
>> --- /dev/null
>> +++ b/OvmfPkg/CpuHotplugSmm/ApicId.h
>> @@ -0,0 +1,23 @@
>> +/** @file
>> +=C2=A0 Type and macro definitions for representing and printing APIC ID=
s,
>> compatibly
>> +=C2=A0 with the LocalApicLib and PrintLib classes, respectively.
>> +
>> +=C2=A0 Copyright (c) 2020, Red Hat, Inc.
>> +
>> +=C2=A0 SPDX-License-Identifier: BSD-2-Clause-Patent
>> +**/
>> +
>> +#ifndef APIC_ID_H_
>> +#define APIC_ID_H_
>> +
>> +//
>> +// The type that LocalApicLib represents an APIC ID with.
>> +//
>> +typedef UINT32 APIC_ID;
>> +
>> +//
>> +// The PrintLib conversion specification for formatting an APIC_ID.
>> +//
>> +#define FMT_APIC_ID "0x%08x"
>> +
>> +#endif // APIC_ID_H_
>> diff --git a/OvmfPkg/CpuHotplugSmm/QemuCpuhp.h
>> b/OvmfPkg/CpuHotplugSmm/QemuCpuhp.h
>> index 82f88f0b73bb..8adaa0ad91f0 100644
>> --- a/OvmfPkg/CpuHotplugSmm/QemuCpuhp.h
>> +++ b/OvmfPkg/CpuHotplugSmm/QemuCpuhp.h
>> @@ -1,47 +1,61 @@
>> =C2=A0 /** @file
>> -=C2=A0 Simple wrapper functions that access QEMU's modern CPU hotplug
>> register
>> -=C2=A0 block.
>> +=C2=A0 Simple wrapper functions and utility functions that access QEMU'=
s
>> modern CPU
>> +=C2=A0 hotplug register block.
>> =C2=A0 -=C2=A0 These functions thinly wrap some of the registers describ=
ed in
>> +=C2=A0 These functions manipulate some of the registers described in
>> =C2=A0=C2=A0=C2=A0 "docs/specs/acpi_cpu_hotplug.txt" in the QEMU source.=
 IO Ports are
>> accessed
>> =C2=A0=C2=A0=C2=A0 via EFI_MM_CPU_IO_PROTOCOL. If a protocol call fails,=
 these
>> functions don't
>> =C2=A0=C2=A0=C2=A0 return.
>> =C2=A0 =C2=A0=C2=A0=C2=A0 Copyright (c) 2020, Red Hat, Inc.
>> =C2=A0 =C2=A0=C2=A0=C2=A0 SPDX-License-Identifier: BSD-2-Clause-Patent
>> =C2=A0 **/
>> =C2=A0 =C2=A0 #ifndef QEMU_CPUHP_H_
>> =C2=A0 #define QEMU_CPUHP_H_
>> =C2=A0 =C2=A0 #include <Protocol/MmCpuIo.h>=C2=A0 // EFI_MM_CPU_IO_PROTO=
COL
>> +#include <Uefi/UefiBaseType.h> // EFI_STATUS
>> +
>> +#include "ApicId.h"=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0 // APIC_ID
>> =C2=A0 =C2=A0 UINT32
>> =C2=A0 QemuCpuhpReadCommandData2 (
>> =C2=A0=C2=A0=C2=A0 IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo
>> =C2=A0=C2=A0=C2=A0 );
>> =C2=A0 =C2=A0 UINT8
>> =C2=A0 QemuCpuhpReadCpuStatus (
>> =C2=A0=C2=A0=C2=A0 IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo
>> =C2=A0=C2=A0=C2=A0 );
>> =C2=A0 =C2=A0 UINT32
>> =C2=A0 QemuCpuhpReadCommandData (
>> =C2=A0=C2=A0=C2=A0 IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo
>> =C2=A0=C2=A0=C2=A0 );
>> =C2=A0 =C2=A0 VOID
>> =C2=A0 QemuCpuhpWriteCpuSelector (
>> =C2=A0=C2=A0=C2=A0 IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo,
>> =C2=A0=C2=A0=C2=A0 IN UINT32=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0 Selector
>> =C2=A0=C2=A0=C2=A0 );
>> =C2=A0 =C2=A0 VOID
>> =C2=A0 QemuCpuhpWriteCommand (
>> =C2=A0=C2=A0=C2=A0 IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo,
>> =C2=A0=C2=A0=C2=A0 IN UINT8=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0 Command
>> =C2=A0=C2=A0=C2=A0 );
>> =C2=A0 +EFI_STATUS
>> +QemuCpuhpCollectApicIds (
>> +=C2=A0 IN=C2=A0 CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo,
>> +=C2=A0 IN=C2=A0 UINT32=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 PossibleCpuCount,
>> +=C2=A0 IN=C2=A0 UINT32=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 ApicIdCount,
>> +=C2=A0 OUT APIC_ID=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
 *PluggedApicIds,
>> +=C2=A0 OUT UINT32=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0 *PluggedCount,
>> +=C2=A0 OUT APIC_ID=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
 *ToUnplugApicIds,
>> +=C2=A0 OUT UINT32=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0 *ToUnplugCount
>> +=C2=A0 );
>> +
>> =C2=A0 #endif // QEMU_CPUHP_H_
>> diff --git a/OvmfPkg/CpuHotplugSmm/QemuCpuhp.c
>> b/OvmfPkg/CpuHotplugSmm/QemuCpuhp.c
>> index 31e46f51934a..8d4a6693c8d6 100644
>> --- a/OvmfPkg/CpuHotplugSmm/QemuCpuhp.c
>> +++ b/OvmfPkg/CpuHotplugSmm/QemuCpuhp.c
>> @@ -1,27 +1,27 @@
>> =C2=A0 /** @file
>> -=C2=A0 Simple wrapper functions that access QEMU's modern CPU hotplug
>> register
>> -=C2=A0 block.
>> +=C2=A0 Simple wrapper functions and utility functions that access QEMU'=
s
>> modern CPU
>> +=C2=A0 hotplug register block.
>> =C2=A0 -=C2=A0 These functions thinly wrap some of the registers describ=
ed in
>> +=C2=A0 These functions manipulate some of the registers described in
>> =C2=A0=C2=A0=C2=A0 "docs/specs/acpi_cpu_hotplug.txt" in the QEMU source.=
 IO Ports are
>> accessed
>> =C2=A0=C2=A0=C2=A0 via EFI_MM_CPU_IO_PROTOCOL. If a protocol call fails,=
 these
>> functions don't
>> =C2=A0=C2=A0=C2=A0 return.
>> =C2=A0 =C2=A0=C2=A0=C2=A0 Copyright (c) 2020, Red Hat, Inc.
>> =C2=A0 =C2=A0=C2=A0=C2=A0 SPDX-License-Identifier: BSD-2-Clause-Patent
>> =C2=A0 **/
>> =C2=A0 =C2=A0 #include <IndustryStandard/Q35MchIch9.h>=C2=A0=C2=A0=C2=A0=
=C2=A0 // ICH9_CPU_HOTPLUG_BASE
>> =C2=A0 #include <IndustryStandard/QemuCpuHotplug.h> // QEMU_CPUHP_R_CMD_=
DATA2
>> =C2=A0 #include <Library/BaseLib.h>=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 // CpuDeadLoop=
()
>> =C2=A0 #include <Library/DebugLib.h>=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 // DEBUG()
>> =C2=A0 =C2=A0 #include "QemuCpuhp.h"
>> =C2=A0 =C2=A0 UINT32
>> =C2=A0 QemuCpuhpReadCommandData2 (
>> =C2=A0=C2=A0=C2=A0 IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo
>> =C2=A0=C2=A0=C2=A0 )
>> =C2=A0 {
>> =C2=A0=C2=A0=C2=A0 UINT32=C2=A0=C2=A0=C2=A0=C2=A0 CommandData2;
>> @@ -115,22 +115,187 @@ QemuCpuhpWriteCpuSelector (
>> =C2=A0 =C2=A0 VOID
>> =C2=A0 QemuCpuhpWriteCommand (
>> =C2=A0=C2=A0=C2=A0 IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo,
>> =C2=A0=C2=A0=C2=A0 IN UINT8=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0 Command
>> =C2=A0=C2=A0=C2=A0 )
>> =C2=A0 {
>> =C2=A0=C2=A0=C2=A0 EFI_STATUS Status;
>> =C2=A0 =C2=A0=C2=A0=C2=A0 Status =3D MmCpuIo->Io.Write (
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 MmCpuIo,
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 MM_IO_UINT8,
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 ICH9_CPU_HOTPLUG_BASE + QEMU_CPUHP_W_CMD,
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 1,
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 &Command
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 );
>> =C2=A0=C2=A0=C2=A0 if (EFI_ERROR (Status)) {
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 DEBUG ((DEBUG_ERROR, "%a: %r\n", __FUNCTI=
ON__, Status));
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ASSERT (FALSE);
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 CpuDeadLoop ();
>> =C2=A0=C2=A0=C2=A0 }
>> =C2=A0 }
>> +
>> +/**
>> +=C2=A0 Collect the APIC IDs of
>> +=C2=A0 - the CPUs that have been hot-plugged,
>> +=C2=A0 - the CPUs that are about to be hot-unplugged.
>> +
>> +=C2=A0 This function only scans for events -- it does not modify them -=
-
>> in the
>> +=C2=A0 hotplug registers.
>> +
>> +=C2=A0 On error, the contents of the output parameters are undefined.
>> +
>> +=C2=A0 @param[in] MmCpuIo=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0 The EFI_MM_CPU_IO_PROTOCOL instance for
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 accessing IO Ports.
>> +
>> +=C2=A0 @param[in] PossibleCpuCount=C2=A0 The number of possible CPUs in=
 the
>> system. Must
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 be positive.
>=20
> Maybe nitpicking: "positive (non zero)"?

Zero is not positive, zero is zero. Positive implies nonzero. :)

Thanks
Laszlo

>=20
>> +
>> +=C2=A0 @param[in] ApicIdCount=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 The n=
umber of elements each one of the
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 PluggedApicIds and ToUnplugApicIds
>> arrays can
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 accommodate. Must be positive.
>> +
>> +=C2=A0 @param[out] PluggedApicIds=C2=A0=C2=A0 The APIC IDs of the CPUs =
that have been
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 hot-plugged.
>> +
>> +=C2=A0 @param[out] PluggedCount=C2=A0=C2=A0=C2=A0=C2=A0 The number of f=
illed-in APIC IDs in
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 PluggedApicIds.
>> +
>> +=C2=A0 @param[out] ToUnplugApicIds=C2=A0 The APIC IDs of the CPUs that =
are
>> about to be
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 hot-unplugged.
>> +
>> +=C2=A0 @param[out] ToUnplugCount=C2=A0=C2=A0=C2=A0 The number of filled=
-in APIC IDs in
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ToUnplugApicIds.
>> +
>> +=C2=A0 @retval EFI_INVALID_PARAMETER=C2=A0 PossibleCpuCount is zero, or
>> ApicIdCount is
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 zero.
>> +
>> +=C2=A0 @retval EFI_PROTOCOL_ERROR=C2=A0=C2=A0=C2=A0=C2=A0 Invalid bitma=
p detected in the
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 QEMU_CPUHP_R_CPU_STAT regi=
ster.
>> +
>> +=C2=A0 @retval EFI_BUFFER_TOO_SMALL=C2=A0=C2=A0 There was an attempt to=
 place more than
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ApicIdCount APIC IDs into =
one of the
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 PluggedApicIds and ToUnplu=
gApicIds
>> arrays.
>> +
>> +=C2=A0 @retval EFI_SUCCESS=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0 Output parameters have been set
>> successfully.
>> +**/
>> +EFI_STATUS
>> +QemuCpuhpCollectApicIds (
>> +=C2=A0 IN=C2=A0 CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo,
>> +=C2=A0 IN=C2=A0 UINT32=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 PossibleCpuCount,
>> +=C2=A0 IN=C2=A0 UINT32=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 ApicIdCount,
>> +=C2=A0 OUT APIC_ID=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
 *PluggedApicIds,
>> +=C2=A0 OUT UINT32=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0 *PluggedCount,
>> +=C2=A0 OUT APIC_ID=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
 *ToUnplugApicIds,
>> +=C2=A0 OUT UINT32=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0 *ToUnplugCount
>> +=C2=A0 )
>> +{
>> +=C2=A0 UINT32 CurrentSelector;
>> +
>> +=C2=A0 if (PossibleCpuCount =3D=3D 0 || ApicIdCount =3D=3D 0) {
>> +=C2=A0=C2=A0=C2=A0 return EFI_INVALID_PARAMETER;
>> +=C2=A0 }
>> +
>> +=C2=A0 *PluggedCount =3D 0;
>> +=C2=A0 *ToUnplugCount =3D 0;
>> +
>> +=C2=A0 CurrentSelector =3D 0;
>> +=C2=A0 do {
>> +=C2=A0=C2=A0=C2=A0 UINT32=C2=A0 PendingSelector;
>> +=C2=A0=C2=A0=C2=A0 UINT8=C2=A0=C2=A0 CpuStatus;
>> +=C2=A0=C2=A0=C2=A0 APIC_ID *ExtendIds;
>> +=C2=A0=C2=A0=C2=A0 UINT32=C2=A0 *ExtendCount;
>> +=C2=A0=C2=A0=C2=A0 APIC_ID NewApicId;
>> +
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 // Write CurrentSelector (which is valid) to the CPU=
 selector
>> register.
>> +=C2=A0=C2=A0=C2=A0 // Consequences:
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 // - Other register accesses will be permitted.
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 // - The QEMU_CPUHP_CMD_GET_PENDING command will sta=
rt scanning
>> for a CPU
>> +=C2=A0=C2=A0=C2=A0 //=C2=A0=C2=A0 with pending events at CurrentSelecto=
r (inclusive).
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 QemuCpuhpWriteCpuSelector (MmCpuIo, CurrentSelector)=
;
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 // Write the QEMU_CPUHP_CMD_GET_PENDING command. Con=
sequences
>> +=C2=A0=C2=A0=C2=A0 // (independently of each other):
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 // - If there is a CPU with pending events, starting=
 at
>> CurrentSelector
>> +=C2=A0=C2=A0=C2=A0 //=C2=A0=C2=A0 (inclusive), the CPU selector will be=
 updated to that CPU.
>> Note that
>> +=C2=A0=C2=A0=C2=A0 //=C2=A0=C2=A0 the scanning in QEMU may wrap around,=
 because we must never
>> clear the
>> +=C2=A0=C2=A0=C2=A0 //=C2=A0=C2=A0 event bits.
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 // - The QEMU_CPUHP_RW_CMD_DATA register will return=
 the
>> (possibly updated)
>> +=C2=A0=C2=A0=C2=A0 //=C2=A0=C2=A0 CPU selector value.
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 QemuCpuhpWriteCommand (MmCpuIo, QEMU_CPUHP_CMD_GET_P=
ENDING);
>> +=C2=A0=C2=A0=C2=A0 PendingSelector =3D QemuCpuhpReadCommandData (MmCpuI=
o);
>> +=C2=A0=C2=A0=C2=A0 if (PendingSelector < CurrentSelector) {
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 DEBUG ((DEBUG_VERBOSE, "%a: CurrentSelec=
tor=3D%u
>> PendingSelector=3D%u: "
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 "wrap-around\n", __FUNCTION_=
_, CurrentSelector,
>> PendingSelector));
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 break;
>> +=C2=A0=C2=A0=C2=A0 }
>> +=C2=A0=C2=A0=C2=A0 CurrentSelector =3D PendingSelector;
>> +
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 // Check the known status / event bits for the curre=
ntly selected
>> CPU.
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 CpuStatus =3D QemuCpuhpReadCpuStatus (MmCpuIo);
>> +=C2=A0=C2=A0=C2=A0 if ((CpuStatus & QEMU_CPUHP_STAT_INSERT) !=3D 0) {
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 // The "insert" event guarantees the "en=
abled" status; plus it
>> excludes
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 // the "remove" event.
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if ((CpuStatus & QEMU_CPUHP_STAT_ENABLED=
) =3D=3D 0 ||
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 (CpuStatus & QEM=
U_CPUHP_STAT_REMOVE) !=3D 0) {
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 DEBUG ((DEBUG_ERROR, "%a: Cu=
rrentSelector=3D%u CpuStatus=3D0x%x: "
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 "inconsistent CP=
U status\n", __FUNCTION__, CurrentSelector,
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 CpuStatus));
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 return EFI_PROTOCOL_ERROR;
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 }
>> +
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 DEBUG ((DEBUG_VERBOSE, "%a: CurrentSelec=
tor=3D%u: insert\n",
>> __FUNCTION__,
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 CurrentSelector));
>> +
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ExtendIds=C2=A0=C2=A0 =3D PluggedApicIds=
;
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ExtendCount =3D PluggedCount;
>> +=C2=A0=C2=A0=C2=A0 } else if ((CpuStatus & QEMU_CPUHP_STAT_REMOVE) !=3D=
 0) {
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 DEBUG ((DEBUG_VERBOSE, "%a: CurrentSelec=
tor=3D%u: remove\n",
>> __FUNCTION__,
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 CurrentSelector));
>> +
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ExtendIds=C2=A0=C2=A0 =3D ToUnplugApicId=
s;
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ExtendCount =3D ToUnplugCount;
>> +=C2=A0=C2=A0=C2=A0 } else {
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 DEBUG ((DEBUG_VERBOSE, "%a: CurrentSelec=
tor=3D%u: no event\n",
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 __FUNCTION__, CurrentSelecto=
r));
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 break;
>> +=C2=A0=C2=A0=C2=A0 }
>> +
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 // Save the APIC ID of the CPU with the pending even=
t, to the
>> corresponding
>> +=C2=A0=C2=A0=C2=A0 // APIC ID array.
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 if (*ExtendCount =3D=3D ApicIdCount) {
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 DEBUG ((DEBUG_ERROR, "%a: APIC ID array =
too small\n",
>> __FUNCTION__));
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 return EFI_BUFFER_TOO_SMALL;
>> +=C2=A0=C2=A0=C2=A0 }
>> +=C2=A0=C2=A0=C2=A0 QemuCpuhpWriteCommand (MmCpuIo, QEMU_CPUHP_CMD_GET_A=
RCH_ID);
>> +=C2=A0=C2=A0=C2=A0 NewApicId =3D QemuCpuhpReadCommandData (MmCpuIo);
>> +=C2=A0=C2=A0=C2=A0 DEBUG ((DEBUG_VERBOSE, "%a: ApicId=3D" FMT_APIC_ID "=
\n", __FUNCTION__,
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 NewApicId));
>> +=C2=A0=C2=A0=C2=A0 ExtendIds[(*ExtendCount)++] =3D NewApicId;
>> +
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 // We've processed the CPU with (known) pending even=
ts, but we
>> must never
>> +=C2=A0=C2=A0=C2=A0 // clear events. Therefore we need to advance past t=
his CPU
>> manually;
>> +=C2=A0=C2=A0=C2=A0 // otherwise, QEMU_CPUHP_CMD_GET_PENDING would stick=
 to the
>> currently
>> +=C2=A0=C2=A0=C2=A0 // selected CPU.
>> +=C2=A0=C2=A0=C2=A0 //
>> +=C2=A0=C2=A0=C2=A0 CurrentSelector++;
>> +=C2=A0 } while (CurrentSelector < PossibleCpuCount);
>> +
>> +=C2=A0 DEBUG ((DEBUG_VERBOSE, "%a: PluggedCount=3D%u ToUnplugCount=3D%u=
\n",
>> +=C2=A0=C2=A0=C2=A0 __FUNCTION__, *PluggedCount, *ToUnplugCount));
>> +=C2=A0 return EFI_SUCCESS;
>> +}
>>
>=20
> Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
>=20