All of lore.kernel.org
 help / color / mirror / Atom feed
From: Tom Lendacky <thomas.lendacky@amd.com>
To: Borislav Petkov <bp@alien8.de>, Alexey Kardashevskiy <aik@amd.com>
Cc: kvm@vger.kernel.org, x86@kernel.org,
	linux-kernel@vger.kernel.org,
	Venu Busireddy <venu.busireddy@oracle.com>,
	Tony Luck <tony.luck@intel.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Sean Christopherson <seanjc@google.com>,
	Sandipan Das <sandipan.das@amd.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Michael Roth <michael.roth@amd.com>,
	Mario Limonciello <mario.limonciello@amd.com>,
	Jan Kara <jack@suse.cz>, Ingo Molnar <mingo@redhat.com>,
	Huang Rui <ray.huang@amd.com>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Daniel Sneddon <daniel.sneddon@linux.intel.com>,
	Brijesh Singh <brijesh.singh@amd.com>,
	Arnaldo Carvalho de Melo <acme@redhat.com>,
	Andrew Cooper <andrew.cooper3@citrix.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Adrian Hunter <adrian.hunter@intel.com>,
	"Jason A. Donenfeld" <Jason@zx2c4.com>,
	"H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH kernel v2 2/3] KVM: SEV: Enable data breakpoints in SEV-ES
Date: Thu, 12 Jan 2023 08:32:46 -0600	[thread overview]
Message-ID: <50e9a5df-b574-5fa5-466e-7bed48523897@amd.com> (raw)
In-Reply-To: <Y7/u76mREet2IrtQ@zn.tnic>

On 1/12/23 05:28, Borislav Petkov wrote:
> On Thu, Jan 12, 2023 at 04:45:34PM +1100, Alexey Kardashevskiy wrote:
>> Well, SEV-ES KVM (ES == Encrypted State) does not save/restore them for the
>> guest (well, as I would expect) as the guest registers are not visible to
>> host to save, they are intercepted and the VM does this GHCB dance with
>> VMGEXIT(SVM_EXIT_WRITE_DR7).
> 
> But they're saved in the VMSA, as Table B-3 says.

Correct, when this feature is enabled, the VMRUN execution will restore 
the guest debug registers on guest entry and save them on guest exit.

Thanks,
Tom

> 
>> Well, the only place in APM is that "Table B-3. Swap Types and the AMD APM
>> volume 2", and it is pretty brief, do I miss something?
> 
> I don't understand that question - please elaborate.
> 
> Thx.
> 

  reply	other threads:[~2023-01-12 14:45 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-12-09  4:38 [PATCH kernel v2 0/3] KVM: SEV: Enable AMD SEV-ES DebugSwap Alexey Kardashevskiy
2022-12-09  4:38 ` [PATCH kernel v2 1/3] x86/amd: Cache values in percpu variables Alexey Kardashevskiy
2023-01-10 16:05   ` Borislav Petkov
2023-01-12  5:21     ` Alexey Kardashevskiy
2023-01-12 11:12       ` Borislav Petkov
2022-12-09  4:38 ` [PATCH kernel v2 2/3] KVM: SEV: Enable data breakpoints in SEV-ES Alexey Kardashevskiy
2023-01-10 18:00   ` Borislav Petkov
2023-01-10 19:06     ` Tom Lendacky
2023-01-12  5:45     ` Alexey Kardashevskiy
2023-01-12 11:28       ` Borislav Petkov
2023-01-12 14:32         ` Tom Lendacky [this message]
2022-12-09  4:38 ` [PATCH kernel v2 3/3] x86/sev: Do not handle #VC for DR7 read/write Alexey Kardashevskiy
2023-01-10 20:04   ` Borislav Petkov
2023-01-09  5:20 ` [PATCH kernel v2 0/3] KVM: SEV: Enable AMD SEV-ES DebugSwap Alexey Kardashevskiy
2023-01-10 17:41 ` Borislav Petkov

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=50e9a5df-b574-5fa5-466e-7bed48523897@amd.com \
    --to=thomas.lendacky@amd.com \
    --cc=Jason@zx2c4.com \
    --cc=acme@redhat.com \
    --cc=adrian.hunter@intel.com \
    --cc=aik@amd.com \
    --cc=alexander.shishkin@linux.intel.com \
    --cc=andrew.cooper3@citrix.com \
    --cc=bp@alien8.de \
    --cc=brijesh.singh@amd.com \
    --cc=daniel.sneddon@linux.intel.com \
    --cc=dave.hansen@linux.intel.com \
    --cc=hpa@zytor.com \
    --cc=jack@suse.cz \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mario.limonciello@amd.com \
    --cc=michael.roth@amd.com \
    --cc=mingo@redhat.com \
    --cc=pawan.kumar.gupta@linux.intel.com \
    --cc=pbonzini@redhat.com \
    --cc=peterz@infradead.org \
    --cc=ray.huang@amd.com \
    --cc=sandipan.das@amd.com \
    --cc=seanjc@google.com \
    --cc=tglx@linutronix.de \
    --cc=tony.luck@intel.com \
    --cc=venu.busireddy@oracle.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: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.