From: Andy Lutomirski <luto@amacapital.net> To: Borislav Petkov <bp@alien8.de> Cc: "Tom Lendacky" <thomas.lendacky@amd.com>, linux-arch <linux-arch@vger.kernel.org>, "linux-efi@vger.kernel.org" <linux-efi@vger.kernel.org>, "kvm list" <kvm@vger.kernel.org>, "linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>, "X86 ML" <x86@kernel.org>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, kasan-dev <kasan-dev@googlegroups.com>, "linux-mm@kvack.org" <linux-mm@kvack.org>, iommu@lists.linux-foundation.org, "Radim Krčmář" <rkrcmar@redhat.com>, "Arnd Bergmann" <arnd@arndb.de>, "Jonathan Corbet" <corbet@lwn.net>, "Matt Fleming" <matt@codeblueprint.co.uk>, "Joerg Roedel" <joro@8bytes.org>, "Konrad Rzeszutek Wilk" <konrad.wilk@oracle.com>, "Paolo Bonzini" <pbonzini@redhat.com>, "Ingo Molnar" <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>, "Andrey Ryabinin" <aryabinin@virtuozzo.com>, "Alexander Potapenko" <glider@google.com> Subject: Re: [RFC PATCH v1 01/18] x86: Set the write-protect cache mode for AMD processors Date: Wed, 27 Apr 2016 08:34:42 -0700 [thread overview] Message-ID: <CALCETrUUL+2CJvo8WWWCw7LB6+osrsx5VfLNBLW=FWiRZchtjg@mail.gmail.com> (raw) In-Reply-To: <20160427153158.GJ21011@pd.tnic> On Wed, Apr 27, 2016 at 8:31 AM, Borislav Petkov <bp@alien8.de> wrote: > On Wed, Apr 27, 2016 at 08:12:56AM -0700, Andy Lutomirski wrote: >> I think there are some errata > > Isn't that addressed by the first branch of the if-test in pat_init(): > > if ((c->x86_vendor == X86_VENDOR_INTEL) && > (((c->x86 == 0x6) && (c->x86_model <= 0xd)) || > ((c->x86 == 0xf) && (c->x86_model <= 0x6)))) { > That's the intent, but I'm unconvinced that it's complete. The reason that WT is in slot 7 is that if it accidentally ends up using the slot 3 entry instead of 7 (e.g. if a 2M page gets confused due to an erratum we didn't handle or similar), then it falls back to UC, which is safe. But this is mostly moot in this case. There is no safe fallback for WP, but it doesn't really matter, because no one will actually try to use it except on a system will full PAT support anyway. So I'm not really concerned. > > -- > Regards/Gruss, > Boris. > > ECO tip #101: Trim your mails when you reply. -- Andy Lutomirski AMA Capital Management, LLC -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
WARNING: multiple messages have this Message-ID (diff)
From: Andy Lutomirski <luto@amacapital.net> To: Borislav Petkov <bp@alien8.de> Cc: "Tom Lendacky" <thomas.lendacky@amd.com>, linux-arch <linux-arch@vger.kernel.org>, "linux-efi@vger.kernel.org" <linux-efi@vger.kernel.org>, "kvm list" <kvm@vger.kernel.org>, "linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>, "X86 ML" <x86@kernel.org>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, kasan-dev <kasan-dev@googlegroups.com>, "linux-mm@kvack.org" <linux-mm@kvack.org>, iommu@lists.linux-foundation.org, "Radim Krčmář" <rkrcmar@redhat.com>, "Arnd Bergmann" <arnd@arndb.de>, "Jonathan Corbet" <corbet@lwn.net>, "Matt Fleming" <matt@codeblueprint.co.uk>, "Joerg Roedel" <joro@8bytes.org>, "Konrad Rzeszutek Wilk" <konrad.wilk@oracle.com>, "Paolo Bonzini" <pbonzini@redhat.com>, "Ingo Molnar" <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>, "Andrey Ryabinin" <aryabinin@virtuozzo.com>, "Alexander Potapenko" <glider@google.com>, "Thomas Gleixner" <tglx@linutronix.de>, "Dmitry Vyukov" <dvyukov@google.com> Subject: Re: [RFC PATCH v1 01/18] x86: Set the write-protect cache mode for AMD processors Date: Wed, 27 Apr 2016 08:34:42 -0700 [thread overview] Message-ID: <CALCETrUUL+2CJvo8WWWCw7LB6+osrsx5VfLNBLW=FWiRZchtjg@mail.gmail.com> (raw) Message-ID: <20160427153442.iXbTobomsmZrx-UoqHPZY1HML3B7g9mJwjE-eKPh-cc@z> (raw) In-Reply-To: <20160427153158.GJ21011@pd.tnic> On Wed, Apr 27, 2016 at 8:31 AM, Borislav Petkov <bp@alien8.de> wrote: > On Wed, Apr 27, 2016 at 08:12:56AM -0700, Andy Lutomirski wrote: >> I think there are some errata > > Isn't that addressed by the first branch of the if-test in pat_init(): > > if ((c->x86_vendor == X86_VENDOR_INTEL) && > (((c->x86 == 0x6) && (c->x86_model <= 0xd)) || > ((c->x86 == 0xf) && (c->x86_model <= 0x6)))) { > That's the intent, but I'm unconvinced that it's complete. The reason that WT is in slot 7 is that if it accidentally ends up using the slot 3 entry instead of 7 (e.g. if a 2M page gets confused due to an erratum we didn't handle or similar), then it falls back to UC, which is safe. But this is mostly moot in this case. There is no safe fallback for WP, but it doesn't really matter, because no one will actually try to use it except on a system will full PAT support anyway. So I'm not really concerned. > > -- > Regards/Gruss, > Boris. > > ECO tip #101: Trim your mails when you reply. -- Andy Lutomirski AMA Capital Management, LLC
next prev parent reply other threads:[~2016-04-27 15:34 UTC|newest] Thread overview: 149+ messages / expand[flat|nested] mbox.gz Atom feed top 2016-04-26 22:55 [RFC PATCH v1 00/18] x86: Secure Memory Encryption (AMD) Tom Lendacky 2016-03-22 13:00 ` Pavel Machek 2016-03-22 13:00 ` Pavel Machek [not found] ` <20160322130058.GA16528-5NIqAleC692hcjWhqY66xCZi+YwRKgec@public.gmane.org> 2016-04-27 14:05 ` Borislav Petkov 2016-04-27 14:05 ` Borislav Petkov 2016-04-27 14:30 ` Pavel Machek 2016-04-27 14:30 ` Pavel Machek 2016-04-27 14:39 ` Borislav Petkov 2016-04-27 14:39 ` Borislav Petkov [not found] ` <20160427143951.GH21011-fF5Pk5pvG8Y@public.gmane.org> 2016-04-27 14:58 ` Pavel Machek 2016-04-27 14:58 ` Pavel Machek 2016-04-27 15:47 ` Pavel Machek 2016-04-27 15:47 ` Pavel Machek 2016-04-27 14:21 ` Tom Lendacky 2016-04-27 14:21 ` Tom Lendacky 2016-04-26 22:55 ` Tom Lendacky 2016-04-26 22:56 ` [RFC PATCH v1 01/18] x86: Set the write-protect cache mode for AMD processors Tom Lendacky 2016-04-26 22:56 ` Tom Lendacky [not found] ` <20160426225604.13567.55443.stgit-qCXWGYdRb2BnqfbPTmsdiZQ+2ll4COg0XqFh9Ls21Oc@public.gmane.org> 2016-04-27 14:33 ` Andy Lutomirski 2016-04-27 14:33 ` Andy Lutomirski 2016-04-27 14:44 ` Tom Lendacky 2016-04-27 14:44 ` Tom Lendacky 2016-04-27 14:47 ` Andy Lutomirski 2016-04-27 14:47 ` Andy Lutomirski [not found] ` <CALCETrV+JzPZjrrqkhWSVfvKQt62Aq8NSW=ZvfdiAi8XKoLi8A-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2016-04-27 15:05 ` Tom Lendacky 2016-04-27 15:05 ` Tom Lendacky 2016-04-27 15:12 ` Andy Lutomirski 2016-04-27 15:12 ` Andy Lutomirski 2016-04-27 15:31 ` Borislav Petkov 2016-04-27 15:31 ` Borislav Petkov 2016-04-27 15:34 ` Andy Lutomirski [this message] 2016-04-27 15:34 ` Andy Lutomirski 2016-04-26 22:56 ` [RFC PATCH v1 02/18] x86: Secure Memory Encryption (SME) build enablement Tom Lendacky 2016-03-22 13:01 ` Pavel Machek 2016-03-22 13:01 ` Pavel Machek 2016-04-27 15:17 ` Tom Lendacky 2016-04-27 15:17 ` Tom Lendacky 2016-04-27 15:30 ` Pavel Machek 2016-04-27 15:30 ` Pavel Machek 2016-04-27 15:41 ` Borislav Petkov 2016-04-27 15:41 ` Borislav Petkov 2016-04-27 16:41 ` Pavel Machek 2016-04-27 17:07 ` Robin Murphy 2016-04-27 17:07 ` Robin Murphy 2016-04-27 17:12 ` Borislav Petkov 2016-04-26 22:56 ` Tom Lendacky 2016-04-26 22:56 ` [RFC PATCH v1 03/18] x86: Secure Memory Encryption (SME) support Tom Lendacky 2016-03-22 13:03 ` Pavel Machek 2016-03-22 13:03 ` Pavel Machek 2016-04-27 16:20 ` Tom Lendacky 2016-04-27 16:20 ` Tom Lendacky 2016-04-26 22:56 ` Tom Lendacky 2016-04-26 22:56 ` [RFC PATCH v1 04/18] x86: Add the Secure Memory Encryption cpu feature Tom Lendacky 2016-04-26 22:56 ` Tom Lendacky 2016-04-26 22:56 ` [RFC PATCH v1 05/18] x86: Handle reduction in physical address size with SME Tom Lendacky 2016-04-26 22:56 ` Tom Lendacky 2016-04-26 22:56 ` [RFC PATCH v1 06/18] x86: Provide general kernel support for memory encryption Tom Lendacky 2016-04-26 22:56 ` Tom Lendacky 2016-04-26 22:57 ` [RFC PATCH v1 07/18] x86: Extend the early_memmap support with additional attrs Tom Lendacky 2016-04-26 22:57 ` Tom Lendacky 2016-04-26 22:57 ` [RFC PATCH v1 08/18] x86: Add support for early encryption/decryption of memory Tom Lendacky 2016-04-26 22:57 ` Tom Lendacky 2016-04-26 22:57 ` [RFC PATCH v1 09/18] x86: Insure that memory areas are encrypted when possible Tom Lendacky 2016-04-26 22:57 ` Tom Lendacky 2016-04-26 22:57 ` [RFC PATCH v1 10/18] x86/efi: Access EFI related tables in the clear Tom Lendacky 2016-04-26 22:57 ` Tom Lendacky [not found] ` <20160426225740.13567.85438.stgit-qCXWGYdRb2BnqfbPTmsdiZQ+2ll4COg0XqFh9Ls21Oc@public.gmane.org> 2016-05-10 13:43 ` Matt Fleming 2016-05-10 13:43 ` Matt Fleming [not found] ` <20160510134358.GR2839-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org> 2016-05-10 13:57 ` Borislav Petkov 2016-05-10 13:57 ` Borislav Petkov 2016-05-12 18:20 ` Tom Lendacky 2016-05-12 18:20 ` Tom Lendacky 2016-05-24 14:54 ` Tom Lendacky 2016-05-24 14:54 ` Tom Lendacky 2016-05-25 16:09 ` Daniel Kiper 2016-05-25 16:09 ` Daniel Kiper 2016-05-25 19:30 ` Matt Fleming 2016-05-25 19:30 ` Matt Fleming 2016-05-26 13:45 ` Tom Lendacky 2016-05-26 13:45 ` Tom Lendacky 2016-06-08 10:07 ` Matt Fleming 2016-06-08 10:07 ` Matt Fleming 2016-06-09 16:16 ` Tom Lendacky 2016-06-09 16:16 ` Tom Lendacky 2016-06-13 12:03 ` Matt Fleming 2016-06-13 12:03 ` Matt Fleming 2016-06-13 12:34 ` Matt Fleming 2016-06-13 12:34 ` Matt Fleming 2016-06-13 15:16 ` Tom Lendacky 2016-06-13 15:16 ` Tom Lendacky 2016-06-08 11:18 ` Matt Fleming 2016-06-08 11:18 ` Matt Fleming 2016-06-09 18:33 ` Tom Lendacky 2016-06-09 18:33 ` Tom Lendacky 2016-06-13 13:51 ` Matt Fleming 2016-06-13 13:51 ` Matt Fleming [not found] ` <20160613135110.GC2658-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org> 2016-06-15 13:17 ` Tom Lendacky 2016-06-15 13:17 ` Tom Lendacky [not found] ` <57615561.4090502-5C7GfCeVMHo@public.gmane.org> 2016-06-16 14:38 ` Tom Lendacky 2016-06-16 14:38 ` Tom Lendacky 2016-06-17 15:51 ` Matt Fleming 2016-06-17 15:51 ` Matt Fleming 2016-04-26 22:57 ` [RFC PATCH v1 11/18] x86: Decrypt trampoline area if memory encryption is active Tom Lendacky 2016-04-26 22:57 ` Tom Lendacky 2016-04-26 22:58 ` [RFC PATCH v1 12/18] x86: Access device tree in the clear Tom Lendacky 2016-04-26 22:58 ` Tom Lendacky 2016-04-26 22:58 ` [RFC PATCH v1 13/18] x86: DMA support for memory encryption Tom Lendacky 2016-04-26 22:58 ` Tom Lendacky 2016-04-29 7:17 ` Konrad Rzeszutek Wilk 2016-04-29 15:12 ` Tom Lendacky 2016-04-29 15:12 ` Tom Lendacky 2016-04-29 16:27 ` Konrad Rzeszutek Wilk [not found] ` <20160429162757.GA1191-he5eyhs8q0BAdwtm4QZOy9BPR1lH4CV8@public.gmane.org> 2016-04-29 23:49 ` Tom Lendacky 2016-04-29 23:49 ` Tom Lendacky 2016-04-26 22:58 ` [RFC PATCH v1 14/18] iommu/amd: AMD IOMMU " Tom Lendacky 2016-04-26 22:58 ` Tom Lendacky 2016-04-26 22:58 ` [RFC PATCH v1 15/18] x86: Enable memory encryption on the APs Tom Lendacky 2016-04-26 22:58 ` Tom Lendacky 2016-05-01 22:10 ` Huang, Kai [not found] ` <f37dd7de-23ad-f70f-c32d-a32f116215ce-VuQAYsv1563Yd54FQh9/CA@public.gmane.org> 2016-05-03 15:59 ` Tom Lendacky 2016-05-03 15:59 ` Tom Lendacky 2016-04-26 22:58 ` [RFC PATCH v1 16/18] x86: Do not specify encrypted memory for VGA mapping Tom Lendacky 2016-04-26 22:58 ` Tom Lendacky 2016-04-26 22:58 ` [RFC PATCH v1 17/18] x86/kvm: Enable Secure Memory Encryption of nested page tables Tom Lendacky 2016-04-26 22:58 ` Tom Lendacky 2016-04-26 22:59 ` [RFC PATCH v1 18/18] x86: Add support to turn on Secure Memory Encryption Tom Lendacky [not found] ` <20160426225904.13567.538.stgit-qCXWGYdRb2BnqfbPTmsdiZQ+2ll4COg0XqFh9Ls21Oc@public.gmane.org> 2016-03-22 13:13 ` Pavel Machek 2016-03-22 13:13 ` Pavel Machek 2016-04-26 22:59 ` Tom Lendacky [not found] ` <20160426225553.13567.19459.stgit-qCXWGYdRb2BnqfbPTmsdiZQ+2ll4COg0XqFh9Ls21Oc@public.gmane.org> 2016-04-27 14:39 ` [RFC PATCH v1 00/18] x86: Secure Memory Encryption (AMD) Andy Lutomirski 2016-04-27 14:39 ` Andy Lutomirski 2016-04-27 20:10 ` Tom Lendacky 2016-04-27 20:10 ` Tom Lendacky 2016-05-02 18:31 ` Andy Lutomirski 2016-05-02 18:31 ` Andy Lutomirski 2016-05-09 15:13 ` Paolo Bonzini 2016-05-09 15:13 ` Paolo Bonzini 2016-05-09 21:08 ` Tom Lendacky 2016-05-09 21:08 ` Tom Lendacky 2016-05-10 11:23 ` Paolo Bonzini 2016-05-10 11:23 ` Paolo Bonzini 2016-05-10 12:04 ` Borislav Petkov 2016-05-10 12:04 ` Borislav Petkov 2016-04-30 6:13 ` Elliott, Robert (Persistent Memory) 2016-04-30 6:13 ` Elliott, Robert (Persistent Memory) [not found] ` <94D0CD8314A33A4D9D801C0FE68B402963918FDA-wwDBVnaDRpYSZAcGdq5asR6epYMZPwEe5NbjCUgZEJk@public.gmane.org> 2016-05-03 15:55 ` Tom Lendacky 2016-05-03 15:55 ` Tom Lendacky -- strict thread matches above, loose matches on Subject: below -- 2016-04-26 22:45 Tom Lendacky 2016-04-26 22:45 ` [RFC PATCH v1 01/18] x86: Set the write-protect cache mode for AMD processors Tom Lendacky 2016-04-26 22:45 ` Tom Lendacky
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to='CALCETrUUL+2CJvo8WWWCw7LB6+osrsx5VfLNBLW=FWiRZchtjg@mail.gmail.com' \ --to=luto@amacapital.net \ --cc=arnd@arndb.de \ --cc=aryabinin@virtuozzo.com \ --cc=bp@alien8.de \ --cc=corbet@lwn.net \ --cc=glider@google.com \ --cc=hpa@zytor.com \ --cc=iommu@lists.linux-foundation.org \ --cc=joro@8bytes.org \ --cc=kasan-dev@googlegroups.com \ --cc=konrad.wilk@oracle.com \ --cc=kvm@vger.kernel.org \ --cc=linux-arch@vger.kernel.org \ --cc=linux-doc@vger.kernel.org \ --cc=linux-efi@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-mm@kvack.org \ --cc=matt@codeblueprint.co.uk \ --cc=mingo@redhat.com \ --cc=pbonzini@redhat.com \ --cc=rkrcmar@redhat.com \ --cc=thomas.lendacky@amd.com \ --cc=x86@kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).