From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=209.132.183.28; helo=mx1.redhat.com; envelope-from=lersek@redhat.com; receiver=edk2-devel@lists.01.org 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 7E43F20355234 for ; Wed, 8 Nov 2017 06:32:50 -0800 (PST) Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id AB48080C18; Wed, 8 Nov 2017 14:36:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com AB48080C18 Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=lersek@redhat.com Received: from lacos-laptop-7.usersys.redhat.com (ovpn-120-142.rdu2.redhat.com [10.10.120.142]) by smtp.corp.redhat.com (Postfix) with ESMTP id 709E95FFEF; Wed, 8 Nov 2017 14:36:49 +0000 (UTC) To: Jian J Wang , edk2-devel@lists.01.org Cc: Eric Dong , Jiewen Yao References: <20171108105224.9560-1-jian.j.wang@intel.com> From: Laszlo Ersek Message-ID: Date: Wed, 8 Nov 2017 15:36:48 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: <20171108105224.9560-1-jian.j.wang@intel.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Wed, 08 Nov 2017 14:36:50 +0000 (UTC) Subject: Re: [PATCH v3] UefiCpuPkg/CpuDxe: Fix multiple entries of RT_CODE in memory map X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 08 Nov 2017 14:32:50 -0000 Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit On 11/08/17 11:52, Jian J Wang wrote: >> v3: >> a. Add comment to explain more on updating memory capabilities >> b. Fix logic hole in updating attributes >> c. Instead of checking illegal memory space address and size, use return >> status of gDS->SetMemorySpaceCapabilities() to skip memory block which >> cannot be updated with new capabilities. > >> v2 >> a. Fix an issue which will cause setting capability failure if size is smaller >> than a page. > > More than one entry of RT_CODE memory might cause boot problem for some > old OSs. This patch will fix this issue to keep OS compatibility as much > as possible. > > More detailed information, please refer to > https://bugzilla.tianocore.org/show_bug.cgi?id=753 > > Cc: Eric Dong > Cc: Jiewen Yao > Cc: Laszlo Ersek > Contributed-under: TianoCore Contribution Agreement 1.1 > Signed-off-by: Jian J Wang > --- > UefiCpuPkg/CpuDxe/CpuPageTable.c | 48 +++++++++++++++++++++++++++++++--------- > 1 file changed, 38 insertions(+), 10 deletions(-) > > diff --git a/UefiCpuPkg/CpuDxe/CpuPageTable.c b/UefiCpuPkg/CpuDxe/CpuPageTable.c > index d312eb66f8..455c713dfc 100644 > --- a/UefiCpuPkg/CpuDxe/CpuPageTable.c > +++ b/UefiCpuPkg/CpuDxe/CpuPageTable.c > @@ -789,7 +789,6 @@ RefreshGcdMemoryAttributesFromPaging ( > UINT64 BaseAddress; > UINT64 PageStartAddress; > UINT64 Attributes; > - UINT64 Capabilities; > BOOLEAN DoUpdate; > UINTN Index; > > @@ -803,7 +802,6 @@ RefreshGcdMemoryAttributesFromPaging ( > GetCurrentPagingContext (&PagingContext); > > DoUpdate = FALSE; > - Capabilities = 0; > Attributes = 0; > BaseAddress = 0; > PageLength = 0; > @@ -813,6 +811,27 @@ RefreshGcdMemoryAttributesFromPaging ( > continue; > } > > + // > + // Sync the actual paging related capabilities back to GCD service first. > + // As a side effect (good one), this can also help to avoid unnecessary > + // memory map entries due to the different capabilities of the same type > + // memory, such as multiple RT_CODE and RT_DATA entries in memory map, > + // which could cause boot failure of some old Linux distro (before v4.3). > + // > + Status = gDS->SetMemorySpaceCapabilities ( > + MemorySpaceMap[Index].BaseAddress, > + MemorySpaceMap[Index].Length, > + MemorySpaceMap[Index].Capabilities | > + EFI_MEMORY_PAGETYPE_MASK > + ); > + if (EFI_ERROR (Status)) { > + // > + // If we cannot udpate the capabilities, we cannot update its > + // attributes either. So just simply skip current block of memory. > + // (1) Can you perhaps add a DEBUG_WARN here? > + continue; > + } > + > if (MemorySpaceMap[Index].BaseAddress >= (BaseAddress + PageLength)) { > // > // Current memory space starts at a new page. Resetting PageLength will > @@ -826,7 +845,9 @@ RefreshGcdMemoryAttributesFromPaging ( > PageLength -= (MemorySpaceMap[Index].BaseAddress - BaseAddress); > } > > - // Sync real page attributes to GCD > + // > + // Sync actual page attributes to GCD > + // > BaseAddress = MemorySpaceMap[Index].BaseAddress; > MemorySpaceLength = MemorySpaceMap[Index].Length; > while (MemorySpaceLength > 0) { > @@ -845,8 +866,6 @@ RefreshGcdMemoryAttributesFromPaging ( > > if (Attributes != (MemorySpaceMap[Index].Attributes & EFI_MEMORY_PAGETYPE_MASK)) { > DoUpdate = TRUE; > - Attributes |= (MemorySpaceMap[Index].Attributes & ~EFI_MEMORY_PAGETYPE_MASK); > - Capabilities = Attributes | MemorySpaceMap[Index].Capabilities; > } else { > DoUpdate = FALSE; > } (2) To me it seems like we can remove the "DoUpdate" local variable completely. Below, we can replace the DoUpdate check with the actual (Attributes != (MemorySpaceMap[Index].Attributes & EFI_MEMORY_PAGETYPE_MASK)) check. The point is that we check the EFI_MEMORY_PAGETYPE_MASK bit-field of the entry's attributes. If they do not match Attributes, we clear the full bit-field, and then add Attributes back in. I.e., we set the bit-field to the desired Attributes. > @@ -854,11 +873,20 @@ RefreshGcdMemoryAttributesFromPaging ( > > Length = MIN (PageLength, MemorySpaceLength); > if (DoUpdate) { > - gDS->SetMemorySpaceCapabilities (BaseAddress, Length, Capabilities); > - gDS->SetMemorySpaceAttributes (BaseAddress, Length, Attributes); > - DEBUG ((DEBUG_INFO, "Update memory space attribute: [%02d] %016lx - %016lx (%08lx -> %08lx)\r\n", > - Index, BaseAddress, BaseAddress + Length - 1, > - MemorySpaceMap[Index].Attributes, Attributes)); > + Status = gDS->SetMemorySpaceAttributes ( > + BaseAddress, > + Length, > + (MemorySpaceMap[Index].Attributes > + & ~EFI_MEMORY_PAGETYPE_MASK) | Attributes > + ); > + ASSERT_EFI_ERROR (Status); > + DEBUG (( > + DEBUG_INFO, > + "Update memory space attribute: [%02d] %016lx - %016lx (%016lx -> %016lx)\r\n", > + Index, BaseAddress, BaseAddress + Length - 1, > + MemorySpaceMap[Index].Attributes, > + (MemorySpaceMap[Index].Attributes & ~EFI_MEMORY_PAGETYPE_MASK) | Attributes > + )); > } (3) I suggest introducing a new variable called "NewMemorySpaceAttributes", and using that for both the debug message and the SetMemorySpaceAttributes() call. (4) Not closely related to this patch, but I'll mention it: the "%d" format specifier is not right for printing UINTN values. The 32-bit/64-bit clean way to print UINTN is: - cast the variable to UINT64 explicitly, - print it with "%lu". Thanks! Laszlo > > PageLength -= Length; >