From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4E1633074A3; Wed, 25 Jun 2025 12:02:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750852975; cv=none; b=ULNRNotwj1Hp5+YGbKKuVrEHPfeg8KD/wixpB7UCUNSjpMh5xPKotbalF0PrO5SsflsiE/AzhI6rcHxiFBwzQAnTIrbMBoF4XkwOZcbCM8/0GUYApFIMdRqKC3aUV/i94LNerL8Du4t2hW8ucYSlU7yaewPzbMkwNdmwF7mSBq8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750852975; c=relaxed/simple; bh=mlZPeHhKRfK4QPugHv3jcEFJFQvdWnNs9NsJQp8STP8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=CniZhWAILlmKlob9GssYjsuRMGoONnwTShd0TMs99+A8M+bU7Uvye5EE1eaVhn51reiF1qe1omNZDOxM/vmh2RJ51z3UxAZ8iXDPoghu4+W7o41Hsc8R12MBd9GJZAGf1hky4sp3bLyVG9/SXV95WjUVkZ3Cl+lzGi7gMYxWfpU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Ej94voEo; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ej94voEo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4A936C4CEEA; Wed, 25 Jun 2025 12:02:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1750852973; bh=mlZPeHhKRfK4QPugHv3jcEFJFQvdWnNs9NsJQp8STP8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Ej94voEoj0IPEuwI8HfFWhG6IxvQc28nyxODnTWBqR5Piq4D+Cpi15LUKzLWStBO8 zjV4FMbheJC5F198UnVnPP98CyeSWC3MId1nxkjZ7PcssbcLhEicNqlBSXShcGUG5x CQAAU1Uc0QFaWNsMXvikE4gs4WydmFTQOpOXlJyRqiS/3C75FnEBn/uzXCIl/hvJDT pyNhvIFdWCS23sXWOFQqnEudEsFlDiNcwrvsg3FQvP5/G0kak91NUFq3hmHxIP8btu R6UMG6d+Xplq3rfzWYPMEL+uZpLl2TtSrC1lHWXB1WQDKxbZIlriv5gp/S2ad2dZ83 qtvlOcnajiMYQ== Date: Wed, 25 Jun 2025 15:02:49 +0300 From: Jarkko Sakkinen To: Stefano Garzarella Cc: linux-kernel@vger.kernel.org, Nicolas Ferre , Naveen N Rao , Sumit Garg , linux-integrity@vger.kernel.org, Peter Huewe , Jens Wiklander , James Bottomley , linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, Christophe Leroy , Nicholas Piggin , Jason Gunthorpe , Michael Ellerman , Alexandre Belloni , Claudiu Beznea , Madhavan Srinivasan Subject: Re: [PATCH v6 4/4] tpm/tpm_svsm: support TPM_CHIP_FLAG_SYNC Message-ID: References: <20250620130810.99069-1-sgarzare@redhat.com> <20250620130810.99069-5-sgarzare@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250620130810.99069-5-sgarzare@redhat.com> On Fri, Jun 20, 2025 at 03:08:10PM +0200, Stefano Garzarella wrote: > From: Stefano Garzarella > > This driver does not support interrupts, and receiving the response is > synchronous with sending the command. > > Enable synchronous send() with TPM_CHIP_FLAG_SYNC, which implies that > ->send() already fills the provided buffer with a response, and ->recv() > is not implemented. > > Keep using the same pre-allocated buffer to avoid having to allocate > it for each command. We need the buffer to have the header required by > the SVSM protocol and the command contiguous in memory. > > Signed-off-by: Stefano Garzarella > --- > v5: > - changed order and parameter names to match tpm_try_transmit() [Jarkko] > v4: > - reworked commit description [Jarkko] > --- > drivers/char/tpm/tpm_svsm.c | 27 +++++++++++---------------- > 1 file changed, 11 insertions(+), 16 deletions(-) > > diff --git a/drivers/char/tpm/tpm_svsm.c b/drivers/char/tpm/tpm_svsm.c > index 0847cbf450b4..f5ba0f64850b 100644 > --- a/drivers/char/tpm/tpm_svsm.c > +++ b/drivers/char/tpm/tpm_svsm.c > @@ -26,37 +26,31 @@ struct tpm_svsm_priv { > }; > > static int tpm_svsm_send(struct tpm_chip *chip, u8 *buf, size_t bufsiz, > - size_t len) > + size_t cmd_len) > { > struct tpm_svsm_priv *priv = dev_get_drvdata(&chip->dev); > int ret; > > - ret = svsm_vtpm_cmd_request_fill(priv->buffer, 0, buf, len); > + ret = svsm_vtpm_cmd_request_fill(priv->buffer, 0, buf, cmd_len); > if (ret) > return ret; > > /* > * The SVSM call uses the same buffer for the command and for the > - * response, so after this call, the buffer will contain the response > - * that can be used by .recv() op. > + * response, so after this call, the buffer will contain the response. > + * > + * Note: we have to use an internal buffer because the device in SVSM > + * expects the svsm_vtpm header + data to be physically contiguous. > */ > - return snp_svsm_vtpm_send_command(priv->buffer); > -} > - > -static int tpm_svsm_recv(struct tpm_chip *chip, u8 *buf, size_t len) > -{ > - struct tpm_svsm_priv *priv = dev_get_drvdata(&chip->dev); > + ret = snp_svsm_vtpm_send_command(priv->buffer); > + if (ret) > + return ret; > > - /* > - * The internal buffer contains the response after we send the command > - * to SVSM. > - */ > - return svsm_vtpm_cmd_response_parse(priv->buffer, buf, len); > + return svsm_vtpm_cmd_response_parse(priv->buffer, buf, bufsiz); > } > > static struct tpm_class_ops tpm_chip_ops = { > .flags = TPM_OPS_AUTO_STARTUP, > - .recv = tpm_svsm_recv, > .send = tpm_svsm_send, > }; > > @@ -85,6 +79,7 @@ static int __init tpm_svsm_probe(struct platform_device *pdev) > > dev_set_drvdata(&chip->dev, priv); > > + chip->flags |= TPM_CHIP_FLAG_SYNC; > err = tpm2_probe(chip); > if (err) > return err; > -- > 2.49.0 > Reviewed-by: Jarkko Sakkinen BR, Jarkko