From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhang Rui Subject: Re: [PATCHv4 14/48] thermal: core: move trips attributes to tz->device.groups Date: Fri, 17 Jun 2016 16:44:56 +0800 Message-ID: <1466153096.9422.34.camel@intel.com> References: <1464675535-2433-1-git-send-email-edubezval@gmail.com> <1464675535-2433-15-git-send-email-edubezval@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1464675535-2433-15-git-send-email-edubezval@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Eduardo Valentin Cc: Linux PM , LKML , Keerthy List-Id: linux-pm@vger.kernel.org On =E4=B8=80, 2016-05-30 at 23:18 -0700, Eduardo Valentin wrote: > Finally, move the last thermal zone sysfs attributes to > tz->device.groups: trips attributes. This requires adding a > attribute_group to thermal_zone_device, creating it dynamically, and > then setting all trips attributes in it. The trips attribute is then > added to the tz->device.groups. >=20 > As the removal of all attributes are handled by device core, the > device > remove calls are not needed anymore. >=20 > Cc: Zhang Rui > Cc: linux-pm@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Eduardo Valentin > --- > =C2=A0drivers/thermal/thermal_core.c | 77 +++++++++++++++++++++------= ----- > ---------- > =C2=A0include/linux/thermal.h=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0|=C2=A0=C2=A02 ++ > =C2=A02 files changed, 41 insertions(+), 38 deletions(-) >=20 > diff --git a/drivers/thermal/thermal_core.c > b/drivers/thermal/thermal_core.c > index ba4f7a9..0b60b04 100644 > --- a/drivers/thermal/thermal_core.c > +++ b/drivers/thermal/thermal_core.c > @@ -1188,8 +1188,9 @@ static const struct attribute_group > *thermal_zone_attribute_groups[] =3D { > =C2=A0 */ > =C2=A0static int create_trip_attrs(struct thermal_zone_device *tz, in= t > mask) > =C2=A0{ > - int indx; > =C2=A0 int size =3D sizeof(struct thermal_attr) * tz->trips; > + struct attribute **attrs; > + int indx; > =C2=A0 > =C2=A0 tz->trip_type_attrs =3D kzalloc(size, GFP_KERNEL); > =C2=A0 if (!tz->trip_type_attrs) > @@ -1210,6 +1211,15 @@ static int create_trip_attrs(struct > thermal_zone_device *tz, int mask) > =C2=A0 } > =C2=A0 } > =C2=A0 > + attrs =3D kzalloc(sizeof(*attrs) * tz->trips * 3 + 1, > GFP_KERNEL); > + if (!attrs) { > + kfree(tz->trip_type_attrs); > + kfree(tz->trip_temp_attrs); > + if (tz->ops->get_trip_hyst) > + kfree(tz->trip_hyst_attrs); > + return -ENOMEM; > + } > + > =C2=A0 for (indx =3D 0; indx < tz->trips; indx++) { > =C2=A0 /* create trip type attribute */ > =C2=A0 snprintf(tz->trip_type_attrs[indx].name, > THERMAL_NAME_LENGTH, > @@ -1220,9 +1230,7 @@ static int create_trip_attrs(struct > thermal_zone_device *tz, int mask) > =C2=A0 tz- > >trip_type_attrs[indx].name; > =C2=A0 tz->trip_type_attrs[indx].attr.attr.mode =3D S_IRUGO; > =C2=A0 tz->trip_type_attrs[indx].attr.show =3D > trip_point_type_show; > - > - device_create_file(&tz->device, > - =C2=A0=C2=A0=C2=A0&tz->trip_type_attrs[indx].attr); > + attrs[indx] =3D &tz->trip_type_attrs[indx].attr.attr; > =C2=A0 > =C2=A0 /* create trip temp attribute */ > =C2=A0 snprintf(tz->trip_temp_attrs[indx].name, > THERMAL_NAME_LENGTH, > @@ -1239,9 +1247,7 @@ static int create_trip_attrs(struct > thermal_zone_device *tz, int mask) > =C2=A0 tz->trip_temp_attrs[indx].attr.store =3D > =C2=A0 trip_point_t > emp_store; > =C2=A0 } > - > - device_create_file(&tz->device, > - =C2=A0=C2=A0=C2=A0&tz->trip_temp_attrs[indx].attr); > + attrs[indx + tz->trips] =3D &tz- > >trip_temp_attrs[indx].attr.attr; > =C2=A0 > =C2=A0 /* create Optional trip hyst attribute */ > =C2=A0 if (!tz->ops->get_trip_hyst) > @@ -1259,45 +1265,38 @@ static int create_trip_attrs(struct > thermal_zone_device *tz, int mask) > =C2=A0 tz->trip_hyst_attrs[indx].attr.store =3D > =C2=A0 trip_point_hyst_store; > =C2=A0 } > - > - device_create_file(&tz->device, > - =C2=A0=C2=A0=C2=A0&tz->trip_hyst_attrs[indx].attr); > + attrs[indx + tz->trips * 2] =3D > + &tz- > >trip_hyst_attrs[indx].attr.attr; > =C2=A0 } > - return 0; > -} > + attrs[tz->trips * 3] =3D NULL; why bother clearing it explicitly? kzalloc already handles this, right? > -static void remove_trip_attrs(struct thermal_zone_device *tz) > -{ > - int indx; > + tz->trips_attribute_group.attrs =3D attrs; > =C2=A0 > - for (indx =3D 0; indx < tz->trips; indx++) { > - device_remove_file(&tz->device, > - =C2=A0=C2=A0=C2=A0&tz->trip_type_attrs[indx].attr); > - device_remove_file(&tz->device, > - =C2=A0=C2=A0=C2=A0&tz->trip_temp_attrs[indx].attr); > - if (tz->ops->get_trip_hyst) > - device_remove_file(&tz->device, > - =C2=A0=C2=A0=C2=A0&tz- > >trip_hyst_attrs[indx].attr); > - } > - kfree(tz->trip_type_attrs); > - kfree(tz->trip_temp_attrs); > - kfree(tz->trip_hyst_attrs); > + return 0; > =C2=A0} > =C2=A0 > -static int thermal_zone_create_device_groups(struct > thermal_zone_device *tz) > +static int thermal_zone_create_device_groups(struct > thermal_zone_device *tz, > + =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0int mask) > =C2=A0{ > =C2=A0 const struct attribute_group **groups; > - int i, size; > + int i, size, result; > + > + result =3D create_trip_attrs(tz, mask); > + if (result) > + return result; > =C2=A0 > - size =3D ARRAY_SIZE(thermal_zone_attribute_groups) + 1; > + /* we need one extra for trips and the NULL to terminate the > array */ > + size =3D ARRAY_SIZE(thermal_zone_attribute_groups) + 2; > =C2=A0 /* This also takes care of API requirement to be NULL > terminated */ > =C2=A0 groups =3D kcalloc(size, sizeof(*groups), GFP_KERNEL); > =C2=A0 if (!groups) > =C2=A0 return -ENOMEM; > =C2=A0 > - for (i =3D 0; i < size - 1; i++) > + for (i =3D 0; i < size - 2; i++) > =C2=A0 groups[i] =3D thermal_zone_attribute_groups[i]; > =C2=A0 > + groups[size - 2] =3D &tz->trips_attribute_group; > + Problem is that, previously, create_trip_attrs() does not handle the case that tz->trips =3D=3D 0 good enough, it happens to not bring big problem. tz->trip_type_attrs/tz->trip_temp_attrs/tz->trip_hyst_attrs is set to=C2=A0ZERO_SIZE_PTR when tz->trips equals 0, kfree() handles this. But registering a sysfs group with one invalid attribute item is wrong. And this causes oops in my machine when test_power driver, which has no trip point, is unloaded. And maybe this is also the root cause of this report=C2=A0http://www.spinics.net/lists/kernel/msg2280260.html Attached is an updated version, which creates trip attributes only if tz->trips > 0, which solves the problem for me. =46rom e1e917e790b70b88bd418545a29b1eefa01a5566 Mon Sep 17 00:00:00 200= 1 =46rom: Eduardo Valentin Date: Mon, 30 May 2016 23:18:21 -0700 Subject: [PATCH] thermal: core: move trips attributes to tz->device.gro= ups =46inally, move the last thermal zone sysfs attributes to tz->device.groups: trips attributes. This requires adding a attribute_group to thermal_zone_device, creating it dynamically, and then setting all trips attributes in it. The trips attribute is then added to the tz->device.groups. As the removal of all attributes are handled by device core, the device remove calls are not needed anymore. Cc: Zhang Rui Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Eduardo Valentin Signed-off-by: Zhang Rui --- =C2=A0drivers/thermal/thermal_core.c | 78 ++++++++++++++++++++++-------= ------------- =C2=A0include/linux/thermal.h=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0|=C2=A0=C2=A02 ++ =C2=A02 files changed, 42 insertions(+), 38 deletions(-) diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_c= ore.c index 657ba02..9926c89 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -1188,8 +1188,9 @@ static const struct attribute_group *thermal_zone= _attribute_groups[] =3D { =C2=A0 */ =C2=A0static int create_trip_attrs(struct thermal_zone_device *tz, int = mask) =C2=A0{ - int indx; =C2=A0 int size =3D sizeof(struct thermal_attr) * tz->trips; + struct attribute **attrs; + int indx; =C2=A0 =C2=A0 tz->trip_type_attrs =3D kzalloc(size, GFP_KERNEL); =C2=A0 if (!tz->trip_type_attrs) @@ -1210,6 +1211,15 @@ static int create_trip_attrs(struct thermal_zone= _device *tz, int mask) =C2=A0 } =C2=A0 } =C2=A0 + attrs =3D kzalloc(sizeof(*attrs) * tz->trips * 3 + 1, GFP_KERNEL); + if (!attrs) { + kfree(tz->trip_type_attrs); + kfree(tz->trip_temp_attrs); + if (tz->ops->get_trip_hyst) + kfree(tz->trip_hyst_attrs); + return -ENOMEM; + } + =C2=A0 for (indx =3D 0; indx < tz->trips; indx++) { =C2=A0 /* create trip type attribute */ =C2=A0 snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH, @@ -1220,9 +1230,7 @@ static int create_trip_attrs(struct thermal_zone_= device *tz, int mask) =C2=A0 tz->trip_type_attrs[indx].name; =C2=A0 tz->trip_type_attrs[indx].attr.attr.mode =3D S_IRUGO; =C2=A0 tz->trip_type_attrs[indx].attr.show =3D trip_point_type_show; - - device_create_file(&tz->device, - =C2=A0=C2=A0=C2=A0&tz->trip_type_attrs[indx].attr); + attrs[indx] =3D &tz->trip_type_attrs[indx].attr.attr; =C2=A0 =C2=A0 /* create trip temp attribute */ =C2=A0 snprintf(tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH, @@ -1239,9 +1247,7 @@ static int create_trip_attrs(struct thermal_zone_= device *tz, int mask) =C2=A0 tz->trip_temp_attrs[indx].attr.store =3D =C2=A0 trip_point_temp_store; =C2=A0 } - - device_create_file(&tz->device, - =C2=A0=C2=A0=C2=A0&tz->trip_temp_attrs[indx].attr); + attrs[indx + tz->trips] =3D &tz->trip_temp_attrs[indx].attr.attr; =C2=A0 =C2=A0 /* create Optional trip hyst attribute */ =C2=A0 if (!tz->ops->get_trip_hyst) @@ -1259,45 +1265,39 @@ static int create_trip_attrs(struct thermal_zon= e_device *tz, int mask) =C2=A0 tz->trip_hyst_attrs[indx].attr.store =3D =C2=A0 trip_point_hyst_store; =C2=A0 } - - device_create_file(&tz->device, - =C2=A0=C2=A0=C2=A0&tz->trip_hyst_attrs[indx].attr); + attrs[indx + tz->trips * 2] =3D + &tz->trip_hyst_attrs[indx].attr.attr; =C2=A0 } - return 0; -} + attrs[tz->trips * 3] =3D NULL; =C2=A0 -static void remove_trip_attrs(struct thermal_zone_device *tz) -{ - int indx; + tz->trips_attribute_group.attrs =3D attrs; =C2=A0 - for (indx =3D 0; indx < tz->trips; indx++) { - device_remove_file(&tz->device, - =C2=A0=C2=A0=C2=A0&tz->trip_type_attrs[indx].attr); - device_remove_file(&tz->device, - =C2=A0=C2=A0=C2=A0&tz->trip_temp_attrs[indx].attr); - if (tz->ops->get_trip_hyst) - device_remove_file(&tz->device, - =C2=A0=C2=A0=C2=A0&tz->trip_hyst_attrs[indx].attr); - } - kfree(tz->trip_type_attrs); - kfree(tz->trip_temp_attrs); - kfree(tz->trip_hyst_attrs); + return 0; =C2=A0} =C2=A0 -static int thermal_zone_create_device_groups(struct thermal_zone_devic= e *tz) +static int thermal_zone_create_device_groups(struct thermal_zone_devic= e *tz, + =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0int mask) =C2=A0{ =C2=A0 const struct attribute_group **groups; - int i, size; + int i, size, result; =C2=A0 - size =3D ARRAY_SIZE(thermal_zone_attribute_groups) + 1; + /* we need one extra for trips and the NULL to terminate the array */ + size =3D ARRAY_SIZE(thermal_zone_attribute_groups) + 2; =C2=A0 /* This also takes care of API requirement to be NULL terminated= */ =C2=A0 groups =3D kcalloc(size, sizeof(*groups), GFP_KERNEL); =C2=A0 if (!groups) =C2=A0 return -ENOMEM; =C2=A0 - for (i =3D 0; i < size - 1; i++) + for (i =3D 0; i < size - 2; i++) =C2=A0 groups[i] =3D thermal_zone_attribute_groups[i]; =C2=A0 + if (tz->trips) { + result =3D create_trip_attrs(tz, mask); + if (result) + return result; + groups[size - 2] =3D &tz->trips_attribute_group; + } + =C2=A0 tz->device.groups =3D groups; =C2=A0 =C2=A0 return 0; @@ -1934,8 +1934,12 @@ struct thermal_zone_device *thermal_zone_device_= register(const char *type, =C2=A0 tz->passive_delay =3D passive_delay; =C2=A0 tz->polling_delay =3D polling_delay; =C2=A0 + /* sys I/F */ =C2=A0 /* Add nodes that are always present via .groups */ - thermal_zone_create_device_groups(tz); + result =3D thermal_zone_create_device_groups(tz, mask); + if (result) + goto unregister; + =C2=A0 /* A new thermal zone needs to be updated anyway. */ =C2=A0 atomic_set(&tz->need_update, 1); =C2=A0 @@ -1947,11 +1951,6 @@ struct thermal_zone_device *thermal_zone_device_= register(const char *type, =C2=A0 return ERR_PTR(result); =C2=A0 } =C2=A0 - /* sys I/F */ - result =3D create_trip_attrs(tz, mask); - if (result) - goto unregister; - =C2=A0 for (count =3D 0; count < trips; count++) { =C2=A0 if (tz->ops->get_trip_type(tz, count, &trip_type)) =C2=A0 set_bit(count, &tz->trips_disabled); @@ -2056,7 +2055,10 @@ void thermal_zone_device_unregister(struct therm= al_zone_device *tz) =C2=A0 =C2=A0 thermal_zone_device_set_polling(tz, 0); =C2=A0 - remove_trip_attrs(tz); + kfree(tz->trip_type_attrs); + kfree(tz->trip_temp_attrs); + kfree(tz->trip_hyst_attrs); + kfree(tz->trips_attribute_group.attrs); =C2=A0 thermal_set_governor(tz, NULL); =C2=A0 =C2=A0 thermal_remove_hwmon_sysfs(tz); diff --git a/include/linux/thermal.h b/include/linux/thermal.h index ee517be..580809c 100644 --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -28,6 +28,7 @@ =C2=A0#include =C2=A0#include =C2=A0#include +#include =C2=A0#include =C2=A0#include =C2=A0 @@ -187,6 +188,7 @@ struct thermal_zone_device { =C2=A0 int id; =C2=A0 char type[THERMAL_NAME_LENGTH]; =C2=A0 struct device device; + struct attribute_group trips_attribute_group; =C2=A0 struct thermal_attr *trip_temp_attrs; =C2=A0 struct thermal_attr *trip_type_attrs; =C2=A0 struct thermal_attr *trip_hyst_attrs; --=C2=A0 2.7.4 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755455AbcFQIpG (ORCPT ); Fri, 17 Jun 2016 04:45:06 -0400 Received: from mga11.intel.com ([192.55.52.93]:11809 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752337AbcFQIpA (ORCPT ); Fri, 17 Jun 2016 04:45:00 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.26,482,1459839600"; d="scan'208";a="720621342" Message-ID: <1466153096.9422.34.camel@intel.com> Subject: Re: [PATCHv4 14/48] thermal: core: move trips attributes to tz->device.groups From: Zhang Rui To: Eduardo Valentin Cc: Linux PM , LKML , Keerthy Date: Fri, 17 Jun 2016 16:44:56 +0800 In-Reply-To: <1464675535-2433-15-git-send-email-edubezval@gmail.com> References: <1464675535-2433-1-git-send-email-edubezval@gmail.com> <1464675535-2433-15-git-send-email-edubezval@gmail.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.18.5.2-0ubuntu3 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 一, 2016-05-30 at 23:18 -0700, Eduardo Valentin wrote: > Finally, move the last thermal zone sysfs attributes to > tz->device.groups: trips attributes. This requires adding a > attribute_group to thermal_zone_device, creating it dynamically, and > then setting all trips attributes in it. The trips attribute is then > added to the tz->device.groups. > > As the removal of all attributes are handled by device core, the > device > remove calls are not needed anymore. > > Cc: Zhang Rui > Cc: linux-pm@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Eduardo Valentin > --- >  drivers/thermal/thermal_core.c | 77 +++++++++++++++++++++----------- > ---------- >  include/linux/thermal.h        |  2 ++ >  2 files changed, 41 insertions(+), 38 deletions(-) > > diff --git a/drivers/thermal/thermal_core.c > b/drivers/thermal/thermal_core.c > index ba4f7a9..0b60b04 100644 > --- a/drivers/thermal/thermal_core.c > +++ b/drivers/thermal/thermal_core.c > @@ -1188,8 +1188,9 @@ static const struct attribute_group > *thermal_zone_attribute_groups[] = { >   */ >  static int create_trip_attrs(struct thermal_zone_device *tz, int > mask) >  { > - int indx; >   int size = sizeof(struct thermal_attr) * tz->trips; > + struct attribute **attrs; > + int indx; >   >   tz->trip_type_attrs = kzalloc(size, GFP_KERNEL); >   if (!tz->trip_type_attrs) > @@ -1210,6 +1211,15 @@ static int create_trip_attrs(struct > thermal_zone_device *tz, int mask) >   } >   } >   > + attrs = kzalloc(sizeof(*attrs) * tz->trips * 3 + 1, > GFP_KERNEL); > + if (!attrs) { > + kfree(tz->trip_type_attrs); > + kfree(tz->trip_temp_attrs); > + if (tz->ops->get_trip_hyst) > + kfree(tz->trip_hyst_attrs); > + return -ENOMEM; > + } > + >   for (indx = 0; indx < tz->trips; indx++) { >   /* create trip type attribute */ >   snprintf(tz->trip_type_attrs[indx].name, > THERMAL_NAME_LENGTH, > @@ -1220,9 +1230,7 @@ static int create_trip_attrs(struct > thermal_zone_device *tz, int mask) >   tz- > >trip_type_attrs[indx].name; >   tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO; >   tz->trip_type_attrs[indx].attr.show = > trip_point_type_show; > - > - device_create_file(&tz->device, > -    &tz->trip_type_attrs[indx].attr); > + attrs[indx] = &tz->trip_type_attrs[indx].attr.attr; >   >   /* create trip temp attribute */ >   snprintf(tz->trip_temp_attrs[indx].name, > THERMAL_NAME_LENGTH, > @@ -1239,9 +1247,7 @@ static int create_trip_attrs(struct > thermal_zone_device *tz, int mask) >   tz->trip_temp_attrs[indx].attr.store = >   trip_point_t > emp_store; >   } > - > - device_create_file(&tz->device, > -    &tz->trip_temp_attrs[indx].attr); > + attrs[indx + tz->trips] = &tz- > >trip_temp_attrs[indx].attr.attr; >   >   /* create Optional trip hyst attribute */ >   if (!tz->ops->get_trip_hyst) > @@ -1259,45 +1265,38 @@ static int create_trip_attrs(struct > thermal_zone_device *tz, int mask) >   tz->trip_hyst_attrs[indx].attr.store = >   trip_point_hyst_store; >   } > - > - device_create_file(&tz->device, > -    &tz->trip_hyst_attrs[indx].attr); > + attrs[indx + tz->trips * 2] = > + &tz- > >trip_hyst_attrs[indx].attr.attr; >   } > - return 0; > -} > + attrs[tz->trips * 3] = NULL; why bother clearing it explicitly? kzalloc already handles this, right? > -static void remove_trip_attrs(struct thermal_zone_device *tz) > -{ > - int indx; > + tz->trips_attribute_group.attrs = attrs; >   > - for (indx = 0; indx < tz->trips; indx++) { > - device_remove_file(&tz->device, > -    &tz->trip_type_attrs[indx].attr); > - device_remove_file(&tz->device, > -    &tz->trip_temp_attrs[indx].attr); > - if (tz->ops->get_trip_hyst) > - device_remove_file(&tz->device, > -    &tz- > >trip_hyst_attrs[indx].attr); > - } > - kfree(tz->trip_type_attrs); > - kfree(tz->trip_temp_attrs); > - kfree(tz->trip_hyst_attrs); > + return 0; >  } >   > -static int thermal_zone_create_device_groups(struct > thermal_zone_device *tz) > +static int thermal_zone_create_device_groups(struct > thermal_zone_device *tz, > +      int mask) >  { >   const struct attribute_group **groups; > - int i, size; > + int i, size, result; > + > + result = create_trip_attrs(tz, mask); > + if (result) > + return result; >   > - size = ARRAY_SIZE(thermal_zone_attribute_groups) + 1; > + /* we need one extra for trips and the NULL to terminate the > array */ > + size = ARRAY_SIZE(thermal_zone_attribute_groups) + 2; >   /* This also takes care of API requirement to be NULL > terminated */ >   groups = kcalloc(size, sizeof(*groups), GFP_KERNEL); >   if (!groups) >   return -ENOMEM; >   > - for (i = 0; i < size - 1; i++) > + for (i = 0; i < size - 2; i++) >   groups[i] = thermal_zone_attribute_groups[i]; >   > + groups[size - 2] = &tz->trips_attribute_group; > + Problem is that, previously, create_trip_attrs() does not handle the case that tz->trips == 0 good enough, it happens to not bring big problem. tz->trip_type_attrs/tz->trip_temp_attrs/tz->trip_hyst_attrs is set to ZERO_SIZE_PTR when tz->trips equals 0, kfree() handles this. But registering a sysfs group with one invalid attribute item is wrong. And this causes oops in my machine when test_power driver, which has no trip point, is unloaded. And maybe this is also the root cause of this report http://www.spinics.net/lists/kernel/msg2280260.html Attached is an updated version, which creates trip attributes only if tz->trips > 0, which solves the problem for me. >>From e1e917e790b70b88bd418545a29b1eefa01a5566 Mon Sep 17 00:00:00 2001 From: Eduardo Valentin Date: Mon, 30 May 2016 23:18:21 -0700 Subject: [PATCH] thermal: core: move trips attributes to tz->device.groups Finally, move the last thermal zone sysfs attributes to tz->device.groups: trips attributes. This requires adding a attribute_group to thermal_zone_device, creating it dynamically, and then setting all trips attributes in it. The trips attribute is then added to the tz->device.groups. As the removal of all attributes are handled by device core, the device remove calls are not needed anymore. Cc: Zhang Rui Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Eduardo Valentin Signed-off-by: Zhang Rui ---  drivers/thermal/thermal_core.c | 78 ++++++++++++++++++++++--------------------  include/linux/thermal.h        |  2 ++  2 files changed, 42 insertions(+), 38 deletions(-) diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index 657ba02..9926c89 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -1188,8 +1188,9 @@ static const struct attribute_group *thermal_zone_attribute_groups[] = {   */  static int create_trip_attrs(struct thermal_zone_device *tz, int mask)  { - int indx;   int size = sizeof(struct thermal_attr) * tz->trips; + struct attribute **attrs; + int indx;     tz->trip_type_attrs = kzalloc(size, GFP_KERNEL);   if (!tz->trip_type_attrs) @@ -1210,6 +1211,15 @@ static int create_trip_attrs(struct thermal_zone_device *tz, int mask)   }   }   + attrs = kzalloc(sizeof(*attrs) * tz->trips * 3 + 1, GFP_KERNEL); + if (!attrs) { + kfree(tz->trip_type_attrs); + kfree(tz->trip_temp_attrs); + if (tz->ops->get_trip_hyst) + kfree(tz->trip_hyst_attrs); + return -ENOMEM; + } +   for (indx = 0; indx < tz->trips; indx++) {   /* create trip type attribute */   snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH, @@ -1220,9 +1230,7 @@ static int create_trip_attrs(struct thermal_zone_device *tz, int mask)   tz->trip_type_attrs[indx].name;   tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO;   tz->trip_type_attrs[indx].attr.show = trip_point_type_show; - - device_create_file(&tz->device, -    &tz->trip_type_attrs[indx].attr); + attrs[indx] = &tz->trip_type_attrs[indx].attr.attr;     /* create trip temp attribute */   snprintf(tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH, @@ -1239,9 +1247,7 @@ static int create_trip_attrs(struct thermal_zone_device *tz, int mask)   tz->trip_temp_attrs[indx].attr.store =   trip_point_temp_store;   } - - device_create_file(&tz->device, -    &tz->trip_temp_attrs[indx].attr); + attrs[indx + tz->trips] = &tz->trip_temp_attrs[indx].attr.attr;     /* create Optional trip hyst attribute */   if (!tz->ops->get_trip_hyst) @@ -1259,45 +1265,39 @@ static int create_trip_attrs(struct thermal_zone_device *tz, int mask)   tz->trip_hyst_attrs[indx].attr.store =   trip_point_hyst_store;   } - - device_create_file(&tz->device, -    &tz->trip_hyst_attrs[indx].attr); + attrs[indx + tz->trips * 2] = + &tz->trip_hyst_attrs[indx].attr.attr;   } - return 0; -} + attrs[tz->trips * 3] = NULL;   -static void remove_trip_attrs(struct thermal_zone_device *tz) -{ - int indx; + tz->trips_attribute_group.attrs = attrs;   - for (indx = 0; indx < tz->trips; indx++) { - device_remove_file(&tz->device, -    &tz->trip_type_attrs[indx].attr); - device_remove_file(&tz->device, -    &tz->trip_temp_attrs[indx].attr); - if (tz->ops->get_trip_hyst) - device_remove_file(&tz->device, -    &tz->trip_hyst_attrs[indx].attr); - } - kfree(tz->trip_type_attrs); - kfree(tz->trip_temp_attrs); - kfree(tz->trip_hyst_attrs); + return 0;  }   -static int thermal_zone_create_device_groups(struct thermal_zone_device *tz) +static int thermal_zone_create_device_groups(struct thermal_zone_device *tz, +      int mask)  {   const struct attribute_group **groups; - int i, size; + int i, size, result;   - size = ARRAY_SIZE(thermal_zone_attribute_groups) + 1; + /* we need one extra for trips and the NULL to terminate the array */ + size = ARRAY_SIZE(thermal_zone_attribute_groups) + 2;   /* This also takes care of API requirement to be NULL terminated */   groups = kcalloc(size, sizeof(*groups), GFP_KERNEL);   if (!groups)   return -ENOMEM;   - for (i = 0; i < size - 1; i++) + for (i = 0; i < size - 2; i++)   groups[i] = thermal_zone_attribute_groups[i];   + if (tz->trips) { + result = create_trip_attrs(tz, mask); + if (result) + return result; + groups[size - 2] = &tz->trips_attribute_group; + } +   tz->device.groups = groups;     return 0; @@ -1934,8 +1934,12 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type,   tz->passive_delay = passive_delay;   tz->polling_delay = polling_delay;   + /* sys I/F */   /* Add nodes that are always present via .groups */ - thermal_zone_create_device_groups(tz); + result = thermal_zone_create_device_groups(tz, mask); + if (result) + goto unregister; +   /* A new thermal zone needs to be updated anyway. */   atomic_set(&tz->need_update, 1);   @@ -1947,11 +1951,6 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type,   return ERR_PTR(result);   }   - /* sys I/F */ - result = create_trip_attrs(tz, mask); - if (result) - goto unregister; -   for (count = 0; count < trips; count++) {   if (tz->ops->get_trip_type(tz, count, &trip_type))   set_bit(count, &tz->trips_disabled); @@ -2056,7 +2055,10 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz)     thermal_zone_device_set_polling(tz, 0);   - remove_trip_attrs(tz); + kfree(tz->trip_type_attrs); + kfree(tz->trip_temp_attrs); + kfree(tz->trip_hyst_attrs); + kfree(tz->trips_attribute_group.attrs);   thermal_set_governor(tz, NULL);     thermal_remove_hwmon_sysfs(tz); diff --git a/include/linux/thermal.h b/include/linux/thermal.h index ee517be..580809c 100644 --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -28,6 +28,7 @@  #include  #include  #include +#include  #include  #include   @@ -187,6 +188,7 @@ struct thermal_zone_device {   int id;   char type[THERMAL_NAME_LENGTH];   struct device device; + struct attribute_group trips_attribute_group;   struct thermal_attr *trip_temp_attrs;   struct thermal_attr *trip_type_attrs;   struct thermal_attr *trip_hyst_attrs; --  2.7.4