Re: [PATCH v3 01/11] i3c: master: Remove i3c_dev_disable_ibi_locked(olddev) on device hotjoin

From: Miquel Raynal <miquel.raynal@bootlin.com>
To: Frank Li <Frank.li@nxp.com>
Cc: Stanley Chu <stanley.chuys@gmail.com>,
	Alexandre Belloni <alexandre.belloni@bootlin.com>,
	Boris Brezillon <boris.brezillon@collabora.com>,
	Parshuram Thombare <pthombar@cadence.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Boris Brezillon <bbrezillon@kernel.org>,
	Arnd Bergmann <arnd@arndb.de>,
	Conor Culhane <conor.culhane@silvaco.com>,
	linux-i3c@lists.infradead.org, linux-kernel@vger.kernel.org,
	imx@lists.linux.dev
Subject: Re: [PATCH v3 01/11] i3c: master: Remove i3c_dev_disable_ibi_locked(olddev) on device hotjoin
Date: Fri, 23 Aug 2024 17:53:20 +0200	[thread overview]
Message-ID: <20240823175320.4948f0ce@xps-13> (raw)
In-Reply-To: <ZsSr+vmyzcmQIN3e@lizhi-Precision-Tower-5810>

Hi Frank,

Frank.li@nxp.com wrote on Tue, 20 Aug 2024 10:45:14 -0400:

> On Tue, Aug 20, 2024 at 09:34:11AM +0800, Stanley Chu wrote:
> > On Tue, Aug 20, 2024 at 12:02 AM Frank Li <Frank.Li@nxp.com> wrote:  
> > >
> > > When a new device hotjoins, a new dynamic address is assigned.
> > > i3c_master_add_i3c_dev_locked() identifies that the device was previously
> > > attached to the bus and locates the olddev.
> > >
> > > i3c_master_add_i3c_dev_locked()
> > > {
> > >     ...
> > >     olddev = i3c_master_search_i3c_dev_duplicate(newdev);
> > >     ...
> > >     if (olddev) {
> > >         ...
> > >         i3c_dev_disable_ibi_locked(olddev);
> > >         ^^^^^^
> > >         The olddev should not receive any commands on the i3c bus as it
> > >         does not exist and has been assigned a new address. This will
> > >         result in NACK or timeout. So remove it.
> > >     }
> > > }
> > >
> > > Fixes: 317bacf960a4 ("i3c: master: add enable(disable) hot join in sys entry")
> > > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > > ---
> > >  drivers/i3c/master.c | 4 +---
> > >  1 file changed, 1 insertion(+), 3 deletions(-)
> > >
> > > diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> > > index 7028f03c2c42e..852b32178b722 100644
> > > --- a/drivers/i3c/master.c
> > > +++ b/drivers/i3c/master.c
> > > @@ -2039,10 +2039,8 @@ int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
> > >                         ibireq.max_payload_len = olddev->ibi->max_payload_len;
> > >                         ibireq.num_slots = olddev->ibi->num_slots;
> > >
> > > -                       if (olddev->ibi->enabled) {
> > > +                       if (olddev->ibi->enabled)
> > >                                 enable_ibi = true;
> > > -                               i3c_dev_disable_ibi_locked(olddev);
> > > -                       }
> > >
> > >                         i3c_dev_free_ibi_locked(olddev);  
> >
> > i3c_dev_free_ibi_locked will still encounter WARN_ON(dev->ibi->enabled).  
> 
> Thank you test it. The below patch should fix this problem.
> 
> https://lore.kernel.org/imx/20240820043818.3352614-1-ravindra.yashvant.shinde@nxp.com/T/#u

It should indeed. With this change added:

Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>

Thanks,
Miquèl