Re: [PATCH] hwmon: (adm1026) Properly terminate sysfs groups (Was:panic about sysfs with adm1026)

From: Jean Delvare
Date: Tue Feb 12 2008 - 03:27:42 EST


Hi Yinghai,

On Mon, 11 Feb 2008 15:39:39 -0800, Yinghai Lu wrote:
> On Feb 10, 2008 10:01 AM, Jean Delvare <khali@xxxxxxxxxxxx> wrote:
> > Yeah, I am an idiot. In 5b34dbcd88251508d02e48ad9b0f9b8232a13ee0 I
> > introduced two new sysfs file groups but forgot to NULL-terminate them.
> > Sorry about that, here's the fix:
> >
> > * * * * *
> >
> > The missing NULL at the end of two sysfs file groups causes a kernel
> > crash when calling sysfs_create_group().
> >
> > Signed-off-by: Jean Delvare <khali@xxxxxxxxxxxx>
> > ---
> > drivers/hwmon/adm1026.c | 2 ++
> > 1 file changed, 2 insertions(+)
> >
> > --- linux-2.6.25-rc0.orig/drivers/hwmon/adm1026.c 2008-02-10 11:21:54.000000000 +0100
> > +++ linux-2.6.25-rc0/drivers/hwmon/adm1026.c 2008-02-10 18:51:00.000000000 +0100
> > @@ -1624,6 +1624,7 @@ static struct attribute *adm1026_attribu
> > &dev_attr_temp3_crit_enable.attr,
> > &dev_attr_temp3_auto_point1_pwm.attr,
> > &dev_attr_temp3_auto_point2_pwm.attr,
> > + NULL
> > };
> >
> > static const struct attribute_group adm1026_group_temp3 = {
> > @@ -1639,6 +1640,7 @@ static struct attribute *adm1026_attribu
> > &sensor_dev_attr_in9_max.dev_attr.attr,
> > &sensor_dev_attr_in9_min.dev_attr.attr,
> > &sensor_dev_attr_in9_alarm.dev_attr.attr,
> > + NULL
> > };
> >
> > static const struct attribute_group adm1026_group_in8_9 = {
> >
> > * * * * *
>
> it works. Thanks

Great, thanks. Mark, please include this patch in your next patch to
Linus for 2.6.25.

> > Yinghai, the bug crept in because I do not have an ADM1026 chip to test
> > my changes. Could you please send a dump of your chip to me, so that I
> > can emulate it? This would avoid similar problems in the future.
> >
> > First you have to find out at which address the ADM1026 chip lives. The
> > first line of "sensors" should tell, otherwise you can run "i2cdetect
> > 1". The ADM1026 can live at 0x2c, 0x2d or 0x2e. Once you know the
> > address, run the following command to get the dump:
> >
> > rmmod adm1026
> > i2cdump 1 0x2d b
>
> LBSuse:/x/kernel.org # ./i2cdetect 1
> WARNING! This program can confuse your I2C bus, cause data loss and worse!
> I will probe file /dev/i2c-1.
> I will probe address range 0x03-0x77.
> Continue? [Y/n] y
> 0 1 2 3 4 5 6 7 8 9 a b c d e f
> 00: -- -- -- -- -- 08 -- -- -- -- -- -- --
> 10: -- -- -- -- -- -- -- -- 18 19 -- -- 1c 1d -- --
> 20: -- -- -- -- -- -- -- -- -- -- -- -- UU UU -- --
> 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
> 40: 40 41 -- -- -- -- -- -- 48 49 4a -- -- -- -- --
> 50: UU UU UU UU UU UU -- -- -- -- -- -- -- -- -- --
> 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
> 70: -- -- -- -- -- -- -- --
> LBSuse:/x/kernel.org # ./i2cdump 1 0x2c b
> Error: Could not set address to 0x2c: Device or resource busy
> LBSuse:/x/kernel.org # ./i2cdump 1 0x2d b
> Error: Could not set address to 0x2d: Device or resource busy

You must unload the adm1026 driver before dumping (see the "rmmod
adm1026" above in my example.)

Thanks,
--
Jean Delvare
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