Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752508AbcKZQSo (ORCPT ); Sat, 26 Nov 2016 11:18:44 -0500 Received: from mga02.intel.com ([134.134.136.20]:3024 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752435AbcKZQSf (ORCPT ); Sat, 26 Nov 2016 11:18:35 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,701,1473145200"; d="scan'208";a="9701928" Date: Sat, 26 Nov 2016 18:15:22 +0200 From: Jarkko Sakkinen To: Nayna Jain Cc: tpmdd-devel@lists.sourceforge.net, peterhuewe@gmx.de, tpmdd@selhorst.net, jgunthorpe@obsidianresearch.com, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v6 1/2] tpm: enhance read_log_of() to support Physical TPM event log Message-ID: <20161126161522.umra77n3yqbpwn5u@intel.com> References: <1480164339-26409-1-git-send-email-nayna@linux.vnet.ibm.com> <1480164339-26409-2-git-send-email-nayna@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1480164339-26409-2-git-send-email-nayna@linux.vnet.ibm.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.6.2-neo (2016-08-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2481 Lines: 78 On Sat, Nov 26, 2016 at 07:45:38AM -0500, Nayna Jain wrote: > Physical TPMs use Open Firmware Device Tree bindings that are similar > to the IBM Power virtual TPM to support event log. However, these > properties store the values in different endianness for Physical > and Virtual TPM. > > This patch fixes the endianness issue by doing appropriate conversion > based on Physical or Virtual TPM. > > Signed-off-by: Nayna Jain > --- > drivers/char/tpm/tpm_of.c | 27 +++++++++++++++++++++++---- > 1 file changed, 23 insertions(+), 4 deletions(-) > > diff --git a/drivers/char/tpm/tpm_of.c b/drivers/char/tpm/tpm_of.c > index 7dee42d7..4b0d5e6 100644 > --- a/drivers/char/tpm/tpm_of.c > +++ b/drivers/char/tpm/tpm_of.c > @@ -27,6 +27,8 @@ int tpm_read_log_of(struct tpm_chip *chip) > const u32 *sizep; > const u64 *basep; > struct tpm_bios_log *log; > + u32 log_size; > + u64 log_base; Maybe just base and size? > > log = &chip->log; > if (chip->dev.parent && chip->dev.parent->of_node) > @@ -41,18 +43,35 @@ int tpm_read_log_of(struct tpm_chip *chip) > if (sizep == NULL || basep == NULL) > return -EIO; > > - if (*sizep == 0) { > + /* > + * For both vtpm/tpm, firmware has log addr and log size in big > + * endian format. But in case of vtpm, there is a method called > + * sml-handover which is run during kernel init even before > + * device tree is setup. This sml-handover function takes care > + * of endianness and writes to sml-base and sml-size in little > + * endian format. For this reason, vtpm doesn't need conversion > + * but physical tpm needs the conversion. > + */ > + if (of_property_match_string(np, "compatible", "IBM,vtpm") < 0) { > + log_size = be32_to_cpup(sizep); > + log_base = be64_to_cpup(basep); > + } else { > + log_size = *sizep; > + log_base = *basep; > + } > + > + if (log_size == 0) { > dev_warn(&chip->dev, "%s: Event log area empty\n", __func__); > return -EIO; > } > > - log->bios_event_log = kmalloc(*sizep, GFP_KERNEL); > + log->bios_event_log = kmalloc(log_size, GFP_KERNEL); > if (!log->bios_event_log) > return -ENOMEM; > > - log->bios_event_log_end = log->bios_event_log + *sizep; > + log->bios_event_log_end = log->bios_event_log + log_size; > > - memcpy(log->bios_event_log, __va(*basep), *sizep); > + memcpy(chip->log.bios_event_log, __va(log_base), log_size); Why did you change the first parameter? > > return 0; > } > -- > 2.5.0 > /Jarkko