Re: [PATCH v8 10/28] sev/i386: add command to initialize the memory encryption context

From: Eduardo Habkost <ehabkost@redhat.com>
To: Brijesh Singh <brijesh.singh@amd.com>
Cc: qemu-devel@nongnu.org,
	Alistair Francis <alistair.francis@xilinx.com>,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	Cornelia Huck <cornelia.huck@de.ibm.com>,
	"Daniel P . Berrange" <berrange@redhat.com>,
	"Dr. David Alan Gilbert" <dgilbert@redhat.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	"Edgar E. Iglesias" <edgar.iglesias@xilinx.com>,
	Eric Blake <eblake@redhat.com>,
	kvm@vger.kernel.org, Marcel Apfelbaum <marcel@redhat.com>,
	Markus Armbruster <armbru@redhat.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Peter Crosthwaite <crosthwaite.peter@gmail.com>,
	Peter Maydell <peter.maydell@linaro.org>,
	Richard Henderson <richard.henderson@linaro.org>,
	Stefan Hajnoczi <stefanha@gmail.com>,
	Thomas Lendacky <Thomas.Lendacky@amd.com>,
	Borislav Petkov <bp@suse.de>,
Subject: Re: [PATCH v8 10/28] sev/i386: add command to initialize the memory encryption context
Date: Mon, 12 Feb 2018 16:57:13 -0200	[thread overview]
Message-ID: <20180212185713.GS13981@localhost.localdomain> (raw)
In-Reply-To: <20180212153715.87555-11-brijesh.singh@amd.com>

On Mon, Feb 12, 2018 at 09:36:57AM -0600, Brijesh Singh wrote:
[...]
> +#define SEV_FW_MAX_ERROR      0x17
> +
> +static const char *const sev_fw_errlist[] = {

This requires anybody reading the code to manually count the
number of items on the array to be sure fw_error_to_str() is
safe.

What about:
  #define SEV_FW_MAX_ERROR ARRAY_SIZE(sev_fw_errlist)

> +    "",
> +    "Platform state is invalid",
> +    "Guest state is invalid",
> +    "Platform configuration is invalid",
> +    "Buffer too small",
> +    "Platform is already owned",
> +    "Certificate is invalid",
> +    "Policy is not allowed",
> +    "Guest is not active",
> +    "Invalid address",
> +    "Bad signature",
> +    "Bad measurement",
> +    "Asid is already owned",
> +    "Invalid ASID",
> +    "WBINVD is required",
> +    "DF_FLUSH is required",
> +    "Guest handle is invalid",
> +    "Invalid command",
> +    "Guest is active",
> +    "Hardware error",
> +    "Hardware unsafe",
> +    "Feature not supported",
> +    "Invalid parameter"
> +};
[...]
> +fw_error_to_str(int code)
> +{
> +    if (code >= SEV_FW_MAX_ERROR) {
> +        return "unknown error";
> +    }
> +
> +    return sev_fw_errlist[code];
> +}
> +

-- 
Eduardo