From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 790AF82215 for ; Tue, 21 Feb 2017 00:32:16 -0800 (PST) Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0928B4E04A; Tue, 21 Feb 2017 08:32:17 +0000 (UTC) Received: from lacos-laptop-7.usersys.redhat.com (ovpn-116-47.phx2.redhat.com [10.3.116.47]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v1L8WEox003194; Tue, 21 Feb 2017 03:32:15 -0500 To: "Fan, Jeff" , "edk2-devel@ml01.01.org" References: <20170220084005.21924-1-jeff.fan@intel.com> <542CF652F8836A4AB8DBFAAD40ED192A4C540B8D@shsmsx102.ccr.corp.intel.com> Cc: "Kinney, Michael D" , "Tian, Feng" , "Yao, Jiewen" From: Laszlo Ersek Message-ID: <15be8f9c-bbd1-fefe-7016-ffde8ae7b436@redhat.com> Date: Tue, 21 Feb 2017 09:32:13 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: <542CF652F8836A4AB8DBFAAD40ED192A4C540B8D@shsmsx102.ccr.corp.intel.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 21 Feb 2017 08:32:17 +0000 (UTC) Subject: Re: [PATCH] UefiCpuPkg/CpuDxe: Add Local APIC memory mapped space in gDS X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 21 Feb 2017 08:32:16 -0000 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit On 02/21/17 02:33, Fan, Jeff wrote: > Laszlo, > > I added my feedback as below. Thanks! > > -----Original Message----- > From: Laszlo Ersek [mailto:lersek@redhat.com] > Sent: Monday, February 20, 2017 5:11 PM > To: Fan, Jeff; edk2-devel@ml01.01.org > Cc: Kinney, Michael D; Tian, Feng; Yao, Jiewen > Subject: Re: [edk2] [PATCH] UefiCpuPkg/CpuDxe: Add Local APIC memory mapped space in gDS > > Hi Jeff, > > On 02/20/17 09:40, Jeff Fan wrote: >> Local APIC memory mapped space should be added into gDS and be allocated. >> Otherwise, UEFI firmware cannot get correct memory map for it. For >> example, SMM profile feature needs to get the completed MMIO map to protect them. >> >> https://bugzilla.tianocore.org/show_bug.cgi?id=390 >> >> Cc: Jiewen Yao >> Cc: Feng Tian >> Cc: Michael D Kinney >> Contributed-under: TianoCore Contribution Agreement 1.0 >> Signed-off-by: Jeff Fan >> --- >> UefiCpuPkg/CpuDxe/CpuDxe.c | 39 >> +++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 39 insertions(+) >> >> diff --git a/UefiCpuPkg/CpuDxe/CpuDxe.c b/UefiCpuPkg/CpuDxe/CpuDxe.c >> index 9fb6d76..71a08cd 100644 >> --- a/UefiCpuPkg/CpuDxe/CpuDxe.c >> +++ b/UefiCpuPkg/CpuDxe/CpuDxe.c >> @@ -887,6 +887,40 @@ IdleLoopEventCallback ( >> CpuSleep (); >> } >> >> +/** >> + Add and allocate CPU local APIC memory mapped space. >> + >> + @param[in]ImageHandle Image handle this driver. >> + >> +**/ >> +VOID >> +AddLocalApicMemorySpace ( >> + IN EFI_HANDLE ImageHandle >> + ) >> +{ >> + EFI_STATUS Status; >> + EFI_PHYSICAL_ADDRESS BaseAddress; >> + >> + BaseAddress = (EFI_PHYSICAL_ADDRESS) GetLocalApicBaseAddress (); >> + Status = gDS->AddMemorySpace ( >> + EfiGcdMemoryTypeMemoryMappedIo, >> + BaseAddress, >> + SIZE_4KB, >> + EFI_MEMORY_UC >> + ); >> + ASSERT_EFI_ERROR (Status); > > (1) This would break OVMF: > >> Loading driver at 0x0007F510000 EntryPoint=0x0007F51027B CpuDxe.efi >> InstallProtocolInterface: [EfiLoadedImageDevicePathProtocol] 7EE08498 >> InstallProtocolInterface: [EfiCpuArchProtocol] 7F522480 >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> >> ASSERT_EFI_ERROR (Status = Access Denied) ASSERT >> .../UefiCpuPkg/CpuDxe/CpuDxe.c(891): !EFI_ERROR (Status) > > The reason for the assertion failure is that we add an uncacheable MMIO resource descriptor HOB for the LAPIC range earlier, in OvmfPkg/PlatformPei. When DXE starts up, it initializes the GCD memory space accordingly, hence the above addition failure. > > There was a similar issue in PciHostBridgeDxe: originally it tried to add uncacheable MMIO space for the PCI bridges' apertures, unconditionally. The solution was to check the GCD memory space map, and: > - for any existing, overlapping entries, check if their attributes were compatible with UC, > - missing gaps were filled with new additions. > > Please see commit 6474f1f156ee ("MdeModulePkg/PciHostBridge: Don't assume resources are fully NonExistent", 2016-02-25). > [Jeff] I agree. Platform Pei could use resource HOB to declare this range. I may sync the code from 6474f1f156ee to CpuDxe. Thanks for considering that! > (2) After the memory space addition, the allocation should be attempted, I agree. But for that too, if it fails, that shouldn't be a fatal error. > [Jeff] Actually, I don't think there is other module(except for Cpu Driver) allocating such range. If other module does it, we need to think if it does make sense and how to fix it. I wonder if it makes sense for CpuDxe to "own" the LAPIC address range. If CpuDxe can be said to "own" the LAPIC, then allocating the range in CpuDxe certainly makes sense. However, given that LocalApicLib is a widely usable (and widely used) library class, I wonder if such an "ownership" can be established. ... Either way, I think enforcing success for the MMIO range allocation is much less problematic than enforcing success for the MMIO range addition. So, from an OVMF platform perspective at least, I guess the second ASSERT_EFI_ERROR() might even stay as-is. Thank you! Laszlo > >> + >> + Status = gDS->AllocateMemorySpace ( >> + EfiGcdAllocateAddress, >> + EfiGcdMemoryTypeMemoryMappedIo, >> + 0, >> + SIZE_4KB, >> + &BaseAddress, >> + ImageHandle, >> + NULL >> + ); >> + ASSERT_EFI_ERROR (Status); >> +} >> >> /** >> Initialize the state information for the CPU Architectural Protocol. >> @@ -947,6 +981,11 @@ InitializeCpu ( >> RefreshGcdMemoryAttributes (); >> >> // >> + // Add and allocate local APIC memory mapped space // >> + AddLocalApicMemorySpace (ImageHandle); >> + >> + // >> // Setup a callback for idle events >> // >> Status = gBS->CreateEventEx ( >> >