Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Message-ID: <37f4ed0d6145dbe1e8724a5d05d0da82b593bf9c.camel@linux.intel.com>
Subject: Re: [PATCH v2] tpm_tis: reserve chip for duration of
 tpm_tis_core_init
From:   Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To:     Jerry Snitselaar <jsnitsel@redhat.com>
Cc:     Dan Williams <dan.j.williams@intel.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Christian Bundy <christianbundy@fraction.io>,
        Peter Huewe <peterhuewe@gmx.de>,
        Jason Gunthorpe <jgg@ziepe.ca>,
        Stefan Berger <stefanb@linux.vnet.ibm.com>,
        stable <stable@vger.kernel.org>, linux-integrity@vger.kernel.org
Date:   Thu, 19 Dec 2019 01:06:40 +0200
In-Reply-To: <20191217171844.huqlj5csr262zkkk@cantor>
References: <20191211231758.22263-1-jsnitsel@redhat.com>
         <20191211235455.24424-1-jsnitsel@redhat.com>
         <5aef0fbe28ed23b963c53d61445b0bac6f108642.camel@linux.intel.com>
         <CAPcyv4h60z889bfbiwvVhsj6MxmOPiPY8ZuPB_skxkZx-N+OGw@mail.gmail.com>
         <20191217020022.knh7uxt4pn77wk5m@cantor>
         <CAPcyv4iepQup4bwMuWzq6r5gdx83hgYckUWFF7yF=rszjz3dtQ@mail.gmail.com>
         <5d0763334def7d7ae1e7cf931ef9b14184dce238.camel@linux.intel.com>
         <20191217171844.huqlj5csr262zkkk@cantor>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo
Content-Type: text/plain; charset="UTF-8"
User-Agent: Evolution 3.34.1-2 
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Tue, 2019-12-17 at 10:18 -0700, Jerry Snitselaar wrote:
> On Tue Dec 17 19, Jarkko Sakkinen wrote:
> > On Mon, 2019-12-16 at 18:14 -0800, Dan Williams wrote:
> > > On Mon, Dec 16, 2019 at 6:00 PM Jerry Snitselaar <jsnitsel@redhat.com> wrote:
> > > > On Mon Dec 16 19, Dan Williams wrote:
> > > > > On Mon, Dec 16, 2019 at 4:59 PM Jarkko Sakkinen
> > > > > <jarkko.sakkinen@linux.intel.com> wrote:
> > > > > > On Wed, 2019-12-11 at 16:54 -0700, Jerry Snitselaar wrote:
> > > > > > > Instead of repeatedly calling tpm_chip_start/tpm_chip_stop when
> > > > > > > issuing commands to the tpm during initialization, just reserve the
> > > > > > > chip after wait_startup, and release it when we are ready to call
> > > > > > > tpm_chip_register.
> > > > > > > 
> > > > > > > Cc: Christian Bundy <christianbundy@fraction.io>
> > > > > > > Cc: Dan Williams <dan.j.williams@intel.com>
> > > > > > > Cc: Peter Huewe <peterhuewe@gmx.de>
> > > > > > > Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> > > > > > > Cc: Jason Gunthorpe <jgg@ziepe.ca>
> > > > > > > Cc: Stefan Berger <stefanb@linux.vnet.ibm.com>
> > > > > > > Cc: stable@vger.kernel.org
> > > > > > > Cc: linux-integrity@vger.kernel.org
> > > > > > > Fixes: a3fbfae82b4c ("tpm: take TPM chip power gating out of tpm_transmit()")
> > > > > > > Fixes: 5b359c7c4372 ("tpm_tis_core: Turn on the TPM before probing IRQ's")
> > > > > > > Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
> > > > > > 
> > > > > > I pushed to my master with minor tweaks and added my tags.
> > > > > > 
> > > > > > Please check before I put it to linux-next.
> > > > > 
> > > > > I don't see it yet here:
> > > > > 
> > > > > http://git.infradead.org/users/jjs/linux-tpmdd.git/shortlog/refs/heads/master
> > > > > 
> > > > > However, I wanted to make sure you captured that this does *not* fix
> > > > > the interrupt issue. I.e. make sure you remove the "Fixes:
> > > > > 5b359c7c4372 ("tpm_tis_core: Turn on the TPM before probing IRQ's")"
> > > > > tag.
> > > > > 
> > > > > With that said, are you going to include the revert of:
> > > > > 
> > > > > 1ea32c83c699 tpm_tis_core: Set TPM_CHIP_FLAG_IRQ before probing for interrupts
> > > > 
> > > > Dan, with the above reverted do you still get the screaming interrupt?
> > > 
> > > Yes, the screaming interrupt goes away, although it is replaced by
> > > these messages when the driver starts:
> > > 
> > > [    3.725131] tpm_tis IFX0740:00: 2.0 TPM (device-id 0x1B, rev-id 16)
> > > [    3.725358] tpm tpm0: tpm_try_transmit: send(): error -5
> > > [    3.725359] tpm tpm0: [Firmware Bug]: TPM interrupt not working,
> > > polling instead
> > > 
> > > If the choice is "error message + polled-mode" vs "pinning a cpu with
> > > interrupts" I'd accept the former, but wanted Jarkko with his
> > > maintainer hat to weigh in.
> > > 
> > > Is there a simple sanity check I can run to see if the TPM is still
> > > operational in this state?
> > 
> > What about T490S?
> > 
> > /Jarkko
> > 
> 
> Hi Jarkko, I'm waiting to hear back from the t490s user, but I imagine
> it still has the problem as well.
> 
> Christian, were you able to try this patch and verify it still
> resolves the issue you were having with the kernel failing to get the
> timeouts and durations from the tpm?

Including those reverts would be a bogus change at this point.

The fix that I already applied obviously fixes an issue even if
it does not fix all the issues.

/Jarkko