From: Dov Murik <dovmurik@linux.ibm.com>
To: Tom Lendacky <thomas.lendacky@amd.com>, qemu-devel@nongnu.org
Cc: "Ashish Kalra" <ashish.kalra@amd.com>,
"Brijesh Singh" <brijesh.singh@amd.com>,
"Eduardo Habkost" <ehabkost@redhat.com>,
"James Bottomley" <jejb@linux.ibm.com>,
"Marcelo Tosatti" <mtosatti@redhat.com>,
"Dr. David Alan Gilbert" <dgilbert@redhat.com>,
"Dov Murik" <dovmurik@linux.ibm.com>,
"Tobin Feldman-Fitzthum" <tobin@linux.ibm.com>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Philippe Mathieu-Daudé" <philmd@redhat.com>
Subject: Re: [PATCH 1/3] sev/i386: Allow launching with -kernel if no OVMF hashes table found
Date: Mon, 1 Nov 2021 19:56:39 +0200 [thread overview]
Message-ID: <ea41121f-80df-f336-c63e-33ede8bac2d5@linux.ibm.com> (raw)
In-Reply-To: <24823e7a-b4e6-150c-df41-a373850301a7@amd.com>
On 01/11/2021 16:25, Tom Lendacky wrote:
> On 11/1/21 5:21 AM, Dov Murik wrote:
>> Commit cff03145ed3c ("sev/i386: Introduce sev_add_kernel_loader_hashes
>> for measured linux boot", 2021-09-30) introduced measured direct boot
>> with -kernel, using an OVMF-designated hashes table which QEMU fills.
>>
>> However, if OVMF doesn't designate such an area, QEMU would completely
>> abort the VM launch. This breaks launching with -kernel using older
>> OVMF images which don't publish the SEV_HASH_TABLE_RV_GUID.
>>
>> Instead, just warn the user that -kernel was supplied by OVMF doesn't
>> specify the GUID for the hashes table. The following warning will be
>> displayed during VM launch:
>>
>> qemu-system-x86_64: warning: SEV: kernel specified but OVMF has
>> no hash table guid
>>
>> Signed-off-by: Dov Murik <dovmurik@linux.ibm.com>
>> Reported-by: Tom Lendacky <thomas.lendacky@amd.com>
>
> Just a few minor comments/questions below, otherwise:
>
> Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
>
>> ---
>> target/i386/sev.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/target/i386/sev.c b/target/i386/sev.c
>> index eede07f11d..682b8ccf6c 100644
>> --- a/target/i386/sev.c
>> +++ b/target/i386/sev.c
>> @@ -1204,7 +1204,7 @@ bool
>> sev_add_kernel_loader_hashes(SevKernelLoaderContext *ctx, Error **errp)
>> int aligned_len;
>> if (!pc_system_ovmf_table_find(SEV_HASH_TABLE_RV_GUID, &data,
>> NULL)) {
>> - error_setg(errp, "SEV: kernel specified but OVMF has no hash
>> table guid");
>> + warn_report("SEV: kernel specified but OVMF has no hash table
>> guid");
>
> Not sure if warn or info would be better, either way works for me,
> though, since this allows the guest to boot now.
OK.
>
> Unrelated to this change, but do we explicitly want to say OVMF? Can't
> another BIOS/UEFI implementation have this support?
>
I don't mind saying "guest firmware" or "VM firmware" or "guest flash"
instead. Note that the function name has "ovmf" in it...
> and should guid be GUID?
I agree; if we change "OVMF" I'll fix that as well.
-Dov
>
> Thanks,
> Tom
>
>> return false;
>> }
>> area = (SevHashTableDescriptor *)data;
>>
next prev parent reply other threads:[~2021-11-01 18:53 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-01 10:21 [PATCH 0/3] SEV: fixes for -kernel launch with incompatible OVMF Dov Murik
2021-11-01 10:21 ` [PATCH 1/3] sev/i386: Allow launching with -kernel if no OVMF hashes table found Dov Murik
2021-11-01 14:25 ` Tom Lendacky
2021-11-01 17:56 ` Dov Murik [this message]
2021-11-03 16:02 ` Daniel P. Berrangé
2021-11-04 18:18 ` Dr. David Alan Gilbert
2021-11-04 18:22 ` Daniel P. Berrangé
2021-11-05 7:41 ` Dov Murik
2021-11-01 10:21 ` [PATCH 2/3] sev/i386: Warn if using -kernel with invalid OVMF hashes table area Dov Murik
2021-11-02 12:36 ` Dr. David Alan Gilbert
2021-11-02 12:56 ` Dov Murik
2021-11-02 18:38 ` Dr. David Alan Gilbert
2021-11-02 19:00 ` Philippe Mathieu-Daudé
2021-11-03 16:07 ` Daniel P. Berrangé
2021-11-05 7:52 ` Dov Murik
2021-11-01 10:21 ` [PATCH 3/3] sev/i386: Perform padding calculations at compile-time Dov Murik
2021-11-02 11:36 ` Dr. David Alan Gilbert
2021-11-02 11:50 ` Dov Murik
2021-11-03 14:49 ` Philippe Mathieu-Daudé
2021-11-02 10:52 ` [PATCH 0/3] SEV: fixes for -kernel launch with incompatible OVMF Brijesh Singh
2021-11-02 13:22 ` Dov Murik
2021-11-02 14:48 ` Brijesh Singh
2021-11-03 14:08 ` Dr. David Alan Gilbert
2021-11-03 15:44 ` Brijesh Singh
2021-11-05 7:38 ` Dov Murik
2021-11-05 18:32 ` Dov Murik
2021-11-08 21:22 ` Brijesh Singh
2021-11-09 7:34 ` Dov Murik
2021-11-03 16:10 ` Daniel P. Berrangé
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=ea41121f-80df-f336-c63e-33ede8bac2d5@linux.ibm.com \
--to=dovmurik@linux.ibm.com \
--cc=ashish.kalra@amd.com \
--cc=brijesh.singh@amd.com \
--cc=dgilbert@redhat.com \
--cc=ehabkost@redhat.com \
--cc=jejb@linux.ibm.com \
--cc=mtosatti@redhat.com \
--cc=pbonzini@redhat.com \
--cc=philmd@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=thomas.lendacky@amd.com \
--cc=tobin@linux.ibm.com \
/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).