From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: [PATCH] vTPM: Fix Atmel timeout bug. Date: Thu, 30 Oct 2014 12:58:22 +0000 Message-ID: <545235EE.4040000@citrix.com> References: <1414674330-2779-1-git-send-email-emilcondrea@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1414674330-2779-1-git-send-email-emilcondrea@gmail.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Emil Condrea , xen-devel@lists.xen.org Cc: dgdegra@tycho.nsa.gov List-Id: xen-devel@lists.xenproject.org On 30/10/14 13:05, Emil Condrea wrote: > Some versions of Atmel TPMs provide invalid values for TPM_CAP_PROP_TIS_TIMEOUT query. > Because timeouts are invalid, every other command after tpm_get_timeouts will fail. > It is a known issue and it was fixed recently in linux kernel tpm_tis.c on 2014-07-29. > This patch does not allow timeouts to be less than standard values. > I tested it on a Dell Latitude E5520 and after making the changes I was able to start vtpmmgr-stubdom. > > Signed-off-by: Emil Condrea > --- > extras/mini-os/tpm_tis.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/extras/mini-os/tpm_tis.c b/extras/mini-os/tpm_tis.c > index b067cb7..81d426a 100644 > --- a/extras/mini-os/tpm_tis.c > +++ b/extras/mini-os/tpm_tis.c > @@ -33,6 +33,11 @@ > #ifndef min > #define min( a, b ) ( ((a) < (b)) ? (a) : (b) ) > #endif > +#define ADJUST_TIMEOUTS_TO_STANDARD(initial,standard,timeout_no) \ > + if((initial) < (standard)){ \ > + (initial) = (standard); \ > + printk("Timeout %c was adjusted to standard value.\n",timeout_no); \ > + } > > #define TPM_HEADER_SIZE 10 > > @@ -997,15 +1002,22 @@ int tpm_get_timeouts(struct tpm_chip *chip) > } > if (timeout) > chip->timeout_a = MICROSECS(timeout * scale); /*Convert to msec */ > + ADJUST_TIMEOUTS_TO_STANDARD(chip->timeout_a,MILLISECS(TIS_SHORT_TIMEOUT),'a'); Surely each of these are just chip->timeout_a = max(MICROSECS(timeout * scale), MILLISECS(TIS_SHORT_TIMEOUT)) Also, are you certain that the units here are correct? The micro vs milli seconds looks odd. ~Andrew