Re: [PATCH 1/8] tpm: block messages while suspended

From: Jason Gunthorpe
Date: Mon Jun 17 2019 - 18:56:36 EST


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 <apronin@xxxxxxxxxxxx>
> > >
> > > 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 <apronin@xxxxxxxxxxxx>
> > > Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
> > >
> > > 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