From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [PATCH 1/8] tpm: block messages while suspended Date: Mon, 17 Jun 2019 19:51:34 -0300 Message-ID: <20190617225134.GA30762@ziepe.ca> References: <20190613180931.65445-1-swboyd@chromium.org> <20190613180931.65445-2-swboyd@chromium.org> <20190613232613.GH22901@ziepe.ca> <5d03e394.1c69fb81.f028c.bffb@mx.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <5d03e394.1c69fb81.f028c.bffb@mx.google.com> Sender: linux-kernel-owner@vger.kernel.org To: Stephen Boyd Cc: Peter Huewe , Jarkko Sakkinen , Andrey Pronin , linux-kernel@vger.kernel.org, Arnd Bergmann , Greg Kroah-Hartman , linux-integrity@vger.kernel.org, devicetree@vger.kernel.org, Duncan Laurie , Guenter Roeck List-Id: devicetree@vger.kernel.org On Fri, Jun 14, 2019 at 11:12:36AM -0700, Stephen Boyd wrote: > Quoting Jason Gunthorpe (2019-06-13 16:26:13) > > On Thu, Jun 13, 2019 at 11:09:24AM -0700, Stephen Boyd wrote: > > > From: Andrey Pronin > > > > > > Other drivers or userspace may initiate sending a message to the tpm > > > while the device itself and the controller of the bus it is on are > > > suspended. That may break the bus driver logic. > > > Block sending messages while the device is suspended. > > > > > > Signed-off-by: Andrey Pronin > > > Signed-off-by: Stephen Boyd > > > > > > I don't think this was ever posted before. > > > > Use a real lock. > > > > To make sure the bit is tested under a lock so that suspend/resume can't > update the bit in parallel? No, just use a real lock, don't make locks out of test bit/set bit Jason