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Subject: Re: [PATCH] KVM: SVM: Add support for KVM_SEV_SEND_CANCEL command
To:     Steve Rutherford <srutherford@google.com>, kvm@vger.kernel.org
References: <20210402014438.1721086-1-srutherford@google.com>
From:   Brijesh Singh <brijesh.singh@amd.com>
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On 4/1/21 8:44 PM, Steve Rutherford wrote:
> After completion of SEND_START, but before SEND_FINISH, the source VMM can
> issue the SEND_CANCEL command to stop a migration. This is necessary so
> that a cancelled migration can restart with a new target later.
>
> Signed-off-by: Steve Rutherford <srutherford@google.com>
> ---
>  .../virt/kvm/amd-memory-encryption.rst        |  9 +++++++
>  arch/x86/kvm/svm/sev.c                        | 24 +++++++++++++++++++
>  include/linux/psp-sev.h                       | 10 ++++++++
>  include/uapi/linux/kvm.h                      |  2 ++
>  4 files changed, 45 insertions(+)


Can we add a new case statement in sev_cmd_buffer_len()
[drivers/crypto/ccp/sev-dev.c] for this command ? I understand that the
command just contains the handle. I have found dyndbg very helpful. If
the command is not added in the sev_cmd_buffer_len() then we don't dump
the command buffer.

With that fixed.

Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>