Received-SPF: pass (google.com: domain of linux-kernel+bounces-61281-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) client-ip=139.178.88.99;
Precedence: bulk
MIME-Version: 1.0
References: <cover.1705965634.git.isaku.yamahata@intel.com> <a4d44b01523c935595c8ee00622ab8766e269ef4.1705965634.git.isaku.yamahata@intel.com>
In-Reply-To: <a4d44b01523c935595c8ee00622ab8766e269ef4.1705965634.git.isaku.yamahata@intel.com>
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Mon, 12 Feb 2024 11:05:39 +0100
Message-ID: <CABgObfbjKb0x+uO=LRLqU8CZ35L7Tgg9B1i0NUwNRG5aQK9ixA@mail.gmail.com>
Subject: Re: [PATCH v18 015/121] KVM: TDX: Retry SEAMCALL on the lack of
 entropy error
To: isaku.yamahata@intel.com
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, 
	isaku.yamahata@gmail.com, erdemaktas@google.com, 
	Sean Christopherson <seanjc@google.com>, Sagi Shahar <sagis@google.com>, Kai Huang <kai.huang@intel.com>, 
	chen.bo@intel.com, hang.yuan@intel.com, tina.zhang@intel.com
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Tue, Jan 23, 2024 at 12:55=E2=80=AFAM <isaku.yamahata@intel.com> wrote:
>
> From: Isaku Yamahata <isaku.yamahata@intel.com>
>
> Some SEAMCALL may return TDX_RND_NO_ENTROPY error when the entropy is
> lacking.  Retry SEAMCALL on the error following rdrand_long() to retry
> RDRAND_RETRY_LOOPS times.
>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>

This patch should not be needed anymore, just...

> +       /* Mimic the existing rdrand_long() to retry RDRAND_RETRY_LOOPS t=
imes. */
> +       retry =3D RDRAND_RETRY_LOOPS;
> +       do {
> +               /* As __seamcall_ret() overwrites out, init out on each l=
oop. */
>                 *out =3D *in;
>                 ret =3D __seamcall_ret(op, out);
> -       } else
> -               ret =3D __seamcall(op, in);

.. use seamcall() and seamcall_ret() here instead of the "__" versions.

Paolo