From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Sakkinen Subject: Re: [PATCH v2] msleep() delays - replace with usleep_range() in TPM 1.2/2.0 generic drivers Date: Sat, 19 Aug 2017 15:16:20 +0300 Message-ID: <20170819121620.4zxnvz5ki76jbbe4@linux.intel.com> References: <20170814180916.GA5574@dev-HP-EliteBook-Folio-1040-G1> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20170814180916.GA5574@dev-HP-EliteBook-Folio-1040-G1> Sender: owner-linux-security-module@vger.kernel.org To: Hamza Attak Cc: tpmdd-devel@lists.sourceforge.net, nigel.edwards@hpe.com, ludo@hpe.com, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org List-Id: tpmdd-devel@lists.sourceforge.net On Mon, Aug 14, 2017 at 07:09:16PM +0100, Hamza Attak wrote: > The patch simply replaces all msleep function calls with usleep_range calls > in the generic drivers. > > Tested with an Infineon TPM 1.2, using the generic tpm-tis module, for a > thousand PCR extends, we see results going from 1m57s unpatched to 40s > with the new patch. We obtain similar results when using the original and > patched tpm_infineon driver, which is also part of the patch. > Similarly with a STM TPM 2.0, using the CRB driver, it takes about 20ms per > extend unpatched and around 7ms with the new patch. > > Note that the PCR consistency is untouched with this patch, each TPM has > been tested with 10 million extends and the aggregated PCR value is > continuously verified to be correct. > > As an extension of this work, this could potentially and easily be applied > to other vendor's drivers. Still, these changes are not included in the > proposed patch as they are untested. > > Signed-off-by: Hamza Attak Applying this. Tested-by: Jarkko Sakkine PS. Your short summary is broken. See how I fixed it. Otherwise, no complains. /Jarkko