From: Sean Christopherson <seanjc@google.com>
To: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
x86@kernel.org,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
Juergen Gross <jgross@suse.com>,
"K. Y. Srinivasan" <kys@microsoft.com>,
Haiyang Zhang <haiyangz@microsoft.com>,
Wei Liu <wei.liu@kernel.org>, Dexuan Cui <decui@microsoft.com>,
Ajay Kaher <ajay.kaher@broadcom.com>,
Jan Kiszka <jan.kiszka@siemens.com>,
Paolo Bonzini <pbonzini@redhat.com>,
Andy Lutomirski <luto@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev,
virtualization@lists.linux.dev, linux-hyperv@vger.kernel.org,
kvm@vger.kernel.org, xen-devel@lists.xenproject.org,
Nikunj A Dadhania <nikunj@amd.com>,
Tom Lendacky <thomas.lendacky@amd.com>
Subject: Re: [PATCH 03/16] x86/tsc: Add helper to register CPU and TSC freq calibration routines
Date: Tue, 11 Feb 2025 09:43:23 -0800 [thread overview]
Message-ID: <Z6uMOyHD3C6-qCXz@google.com> (raw)
In-Reply-To: <20250211173238.GDZ6uJtkVBi8_X7kia@fat_crate.local>
On Tue, Feb 11, 2025, Borislav Petkov wrote:
> On Fri, Jan 31, 2025 at 06:17:05PM -0800, Sean Christopherson wrote:
>
> > Add a TODO to call out that AMD_MEM_ENCRYPT is a mess and doesn't depend on
> > HYPERVISOR_GUEST because it gates both guest and host code.
>
> Why is it a mess?
>
> I don't see it, frankly.
It conflates two very different things: host/bare metal support for memory
encryption, and SEV guest support. For kernels that will never run in a VM,
pulling in all the SEV guest code just to enable host-side support for SME (and
SEV) is very undesirable.
And in this case, because AMD_MEM_ENCRYPT gates both host and guest code, it
can't depend on HYPERVISOR_GUEST like it should, because taking a dependency on
HYPERVISOR_GUEST to enable SME is obviously wrong.
next prev parent reply other threads:[~2025-02-11 17:43 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-02-01 2:17 [PATCH 00/16] x86/tsc: Try to wrangle PV clocks vs. TSC Sean Christopherson
2025-02-01 2:17 ` [PATCH 01/16] x86/tsc: Add a standalone helpers for getting TSC info from CPUID.0x15 Sean Christopherson
2025-02-03 5:55 ` Nikunj A Dadhania
2025-02-03 22:03 ` Sean Christopherson
2025-02-05 22:13 ` Sean Christopherson
2025-02-11 15:01 ` Borislav Petkov
2025-02-11 17:25 ` Sean Christopherson
2025-02-11 18:40 ` Borislav Petkov
2025-02-11 19:03 ` Sean Christopherson
2025-02-01 2:17 ` [PATCH 02/16] x86/tsc: Add standalone helper for getting CPU frequency from CPUID Sean Christopherson
2025-02-01 2:17 ` [PATCH 03/16] x86/tsc: Add helper to register CPU and TSC freq calibration routines Sean Christopherson
2025-02-11 17:32 ` Borislav Petkov
2025-02-11 17:43 ` Sean Christopherson [this message]
2025-02-11 20:32 ` Borislav Petkov
2025-02-12 16:49 ` Tom Lendacky
2025-02-01 2:17 ` [PATCH 04/16] x86/sev: Mark TSC as reliable when configuring Secure TSC Sean Christopherson
2025-02-04 8:02 ` Nikunj A Dadhania
2025-02-01 2:17 ` [PATCH 05/16] x86/sev: Move check for SNP Secure TSC support to tsc_early_init() Sean Christopherson
2025-02-04 8:27 ` Nikunj A Dadhania
2025-02-01 2:17 ` [PATCH 06/16] x86/tdx: Override PV calibration routines with CPUID-based calibration Sean Christopherson
2025-02-04 10:16 ` Nikunj A Dadhania
2025-02-04 19:29 ` Sean Christopherson
2025-02-05 3:56 ` Nikunj A Dadhania
2025-02-01 2:17 ` [PATCH 07/16] x86/acrn: Mark TSC frequency as known when using ACRN for calibration Sean Christopherson
2025-02-01 2:17 ` [PATCH 08/16] x86/tsc: Pass KNOWN_FREQ and RELIABLE as params to registration Sean Christopherson
2025-02-03 14:48 ` Tom Lendacky
2025-02-03 19:52 ` Sean Christopherson
2025-02-01 2:17 ` [PATCH 09/16] x86/tsc: Rejects attempts to override TSC calibration with lesser routine Sean Christopherson
2025-02-01 2:17 ` [PATCH 10/16] x86/paravirt: Move handling of unstable PV clocks into paravirt_set_sched_clock() Sean Christopherson
2025-02-01 2:17 ` [PATCH 11/16] x86/paravirt: Don't use a PV sched_clock in CoCo guests with trusted TSC Sean Christopherson
2025-02-01 2:17 ` [PATCH 12/16] x86/kvmclock: Mark TSC as reliable when it's constant and nonstop Sean Christopherson
2025-02-01 2:17 ` [PATCH 13/16] x86/kvmclock: Get CPU base frequency from CPUID when it's available Sean Christopherson
2025-02-01 2:17 ` [PATCH 14/16] x86/kvmclock: Get TSC frequency from CPUID when its available Sean Christopherson
2025-02-01 2:17 ` [PATCH 15/16] x86/kvmclock: Stuff local APIC bus period when core crystal freq comes from CPUID Sean Christopherson
2025-02-01 2:17 ` [PATCH 16/16] x86/kvmclock: Use TSC for sched_clock if it's constant and non-stop Sean Christopherson
2025-02-07 17:23 ` Sean Christopherson
2025-02-08 18:03 ` Michael Kelley
2025-02-10 16:21 ` Sean Christopherson
2025-02-12 16:44 ` Michael Kelley
2025-02-12 22:55 ` Sean Christopherson
2025-02-11 14:39 ` [PATCH 00/16] x86/tsc: Try to wrangle PV clocks vs. TSC Borislav Petkov
2025-02-11 16:28 ` Sean Christopherson
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=Z6uMOyHD3C6-qCXz@google.com \
--to=seanjc@google.com \
--cc=ajay.kaher@broadcom.com \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=decui@microsoft.com \
--cc=haiyangz@microsoft.com \
--cc=jan.kiszka@siemens.com \
--cc=jgross@suse.com \
--cc=kirill.shutemov@linux.intel.com \
--cc=kvm@vger.kernel.org \
--cc=kys@microsoft.com \
--cc=linux-coco@lists.linux.dev \
--cc=linux-hyperv@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mingo@redhat.com \
--cc=nikunj@amd.com \
--cc=pbonzini@redhat.com \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
--cc=thomas.lendacky@amd.com \
--cc=virtualization@lists.linux.dev \
--cc=wei.liu@kernel.org \
--cc=x86@kernel.org \
--cc=xen-devel@lists.xenproject.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: link
Be 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).