From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nayna Subject: Re: [PATCH v7 1/2] tpm: enhance read_log_of() to support Physical TPM event log Date: Fri, 16 Dec 2016 21:58:13 +0530 Message-ID: <5854161D.6010006@linux.vnet.ibm.com> References: <1481434533-3453-1-git-send-email-nayna@linux.vnet.ibm.com> <1481434533-3453-2-git-send-email-nayna@linux.vnet.ibm.com> <20161212144004.ojrbp6e3whxyydi4@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20161212144004.ojrbp6e3whxyydi4@intel.com> Sender: owner-linux-security-module@vger.kernel.org To: Jarkko Sakkinen 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 List-Id: tpmdd-devel@lists.sourceforge.net On 12/12/2016 08:10 PM, Jarkko Sakkinen wrote: > On Sun, Dec 11, 2016 at 12:35:32AM -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. > > Will other device tree using firmwares than OF use the same bindings? Yes, that is what expected that all other device tree using firmware will also use same bindings. Thanks & Regards, - Nayna > >> 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..de57d4a 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 size; >> + u64 base; >> >> 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) { >> + size = be32_to_cpup(sizep); >> + base = be64_to_cpup(basep); >> + } else { >> + size = *sizep; >> + base = *basep; >> + } >> + >> + if (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(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 + size; >> >> - memcpy(log->bios_event_log, __va(*basep), *sizep); >> + memcpy(log->bios_event_log, __va(base), size); >> >> return 0; >> } >> -- >> 2.5.0 >> > > Reviewed-by: Jarkko Sakkinen > > /Jarkko >