Re: [PATCH v2] power: supply: cpcap-battery: fix invalid usage of list cursor

From: Carl Philipp Klemm <philipp@uvos.xyz>
To: Tony Lindgren <tony@atomide.com>
Cc: zhuguangqing83@gmail.com, Sebastian Reichel <sre@kernel.org>,
	linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] power: supply: cpcap-battery: fix invalid usage of list cursor
Date: Wed, 21 Apr 2021 19:19:33 +0200	[thread overview]
Message-ID: <20210421191933.6fa083e0b2496aedaef4957a@uvos.xyz> (raw)
In-Reply-To: <YIBNDrHlwqn5hrl2@atomide.com>

Looks good to me, but dosent appear to solve the bootup bug.

(this time reply all)

Reviewed-by: Carl Philipp Klemm <philipp@uvos.xyz>
Tested-by: Carl Philipp Klemm <philipp@uvos.xyz>

-- 
Carl Philipp Klemm <philipp@uvos.xyz> <carl@uvos.xyz>

On Wed, 21 Apr 2021 19:04:30 +0300
Tony Lindgren <tony@atomide.com> wrote:

> Hi,
> 
> * zhuguangqing83@gmail.com <zhuguangqing83@gmail.com> [210421 14:38]:
> > From: Guangqing Zhu <zhuguangqing83@gmail.com>
> > 
> > Fix invalid usage of a list_for_each_entry in cpcap_battery_irq_thread().
> > Empty list or fully traversed list points to list head, which is not
> > NULL (and before the first element containing real data).
> > 
> > Signed-off-by: Guangqing Zhu <zhuguangqing83@gmail.com>
> > ---
> > v2:
> >   - Modify commit message and code as suggested by Sebastian.
> 
> Thanks looks OK to me. Looks like there's no flag we need to set there when
> the entry is found, so this should do for the check.
> 
> Hmm I wonder if this just might fix the issue where booting with a USB
> charger connected can hang..
> 
> Reviewed-by: Tony Lindgren <tony@atomide.com>
> 
> > ---
> >  drivers/power/supply/cpcap-battery.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/power/supply/cpcap-battery.c b/drivers/power/supply/cpcap-battery.c
> > index 6d5bcdb9f45d..a3fc0084cda0 100644
> > --- a/drivers/power/supply/cpcap-battery.c
> > +++ b/drivers/power/supply/cpcap-battery.c
> > @@ -786,7 +786,7 @@ static irqreturn_t cpcap_battery_irq_thread(int irq, void *data)
> >  			break;
> >  	}
> >  
> > -	if (!d)
> > +	if (list_entry_is_head(d, &ddata->irq_list, node))
> >  		return IRQ_NONE;
> >  
> >  	latest = cpcap_battery_latest(ddata);
> > -- 
> > 2.17.1
> > 