* Re: [PATCH] gpiolib: fix race condition for gdev->srcu
2025-12-23 8:42 [PATCH] gpiolib: fix race condition for gdev->srcu Paweł Narewski
@ 2025-12-23 20:14 ` kernel test robot
2025-12-24 3:47 ` kernel test robot
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: kernel test robot @ 2025-12-23 20:14 UTC (permalink / raw)
To: Paweł Narewski, linux-gpio
Cc: oe-kbuild-all, linusw, brgl, Paweł Narewski, Jakub Lewalski
Hi Paweł,
kernel test robot noticed the following build errors:
[auto build test ERROR on brgl/gpio/for-next]
[also build test ERROR on linus/master v6.19-rc2 next-20251219]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Pawe-Narewski/gpiolib-fix-race-condition-for-gdev-srcu/20251223-165142
base: https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git gpio/for-next
patch link: https://lore.kernel.org/r/20251223084952.1847489-1-pawel.narewski%40nokia.com
patch subject: [PATCH] gpiolib: fix race condition for gdev->srcu
config: openrisc-allnoconfig (https://download.01.org/0day-ci/archive/20251224/202512240338.Efsr69oP-lkp@intel.com/config)
compiler: or1k-linux-gcc (GCC) 15.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251224/202512240338.Efsr69oP-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202512240338.Efsr69oP-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from include/linux/mm_types.h:13,
from include/linux/mmzone.h:22,
from include/linux/gfp.h:7,
from include/linux/slab.h:16,
from include/linux/resource_ext.h:11,
from include/linux/acpi.h:14,
from drivers/gpio/gpiolib.c:3:
drivers/gpio/gpiolib.c: In function 'gpiochip_add_data_with_key':
>> include/linux/notifier.h:86:35: error: 'struct raw_notifier_head' has no member named 'rwsem'
86 | init_rwsem(&(name)->rwsem); \
| ^~
include/linux/rwsem.h:121:23: note: in definition of macro 'init_rwsem'
121 | __init_rwsem((sem), #sem, &__key); \
| ^~~
drivers/gpio/gpiolib.c:1109:9: note: in expansion of macro 'BLOCKING_INIT_NOTIFIER_HEAD'
1109 | BLOCKING_INIT_NOTIFIER_HEAD(&gdev->line_state_notifier);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
vim +86 include/linux/notifier.h
eabc069401bcf4 Alan Stern 2006-10-04 80
e041c683412d5b Alan Stern 2006-03-27 81 #define ATOMIC_INIT_NOTIFIER_HEAD(name) do { \
e041c683412d5b Alan Stern 2006-03-27 82 spin_lock_init(&(name)->lock); \
e041c683412d5b Alan Stern 2006-03-27 83 (name)->head = NULL; \
e041c683412d5b Alan Stern 2006-03-27 84 } while (0)
e041c683412d5b Alan Stern 2006-03-27 85 #define BLOCKING_INIT_NOTIFIER_HEAD(name) do { \
e041c683412d5b Alan Stern 2006-03-27 @86 init_rwsem(&(name)->rwsem); \
e041c683412d5b Alan Stern 2006-03-27 87 (name)->head = NULL; \
e041c683412d5b Alan Stern 2006-03-27 88 } while (0)
e041c683412d5b Alan Stern 2006-03-27 89 #define RAW_INIT_NOTIFIER_HEAD(name) do { \
e041c683412d5b Alan Stern 2006-03-27 90 (name)->head = NULL; \
e041c683412d5b Alan Stern 2006-03-27 91 } while (0)
e041c683412d5b Alan Stern 2006-03-27 92
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] gpiolib: fix race condition for gdev->srcu
2025-12-23 8:42 [PATCH] gpiolib: fix race condition for gdev->srcu Paweł Narewski
2025-12-23 20:14 ` kernel test robot
@ 2025-12-24 3:47 ` kernel test robot
2025-12-24 6:21 ` kernel test robot
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: kernel test robot @ 2025-12-24 3:47 UTC (permalink / raw)
To: Paweł Narewski, linux-gpio
Cc: llvm, oe-kbuild-all, linusw, brgl, Paweł Narewski,
Jakub Lewalski
Hi Paweł,
kernel test robot noticed the following build errors:
[auto build test ERROR on brgl/gpio/for-next]
[also build test ERROR on linus/master v6.19-rc2 next-20251219]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Pawe-Narewski/gpiolib-fix-race-condition-for-gdev-srcu/20251223-165142
base: https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git gpio/for-next
patch link: https://lore.kernel.org/r/20251223084952.1847489-1-pawel.narewski%40nokia.com
patch subject: [PATCH] gpiolib: fix race condition for gdev->srcu
config: x86_64-kexec (https://download.01.org/0day-ci/archive/20251224/202512240408.wrQcvO0t-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251224/202512240408.wrQcvO0t-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202512240408.wrQcvO0t-lkp@intel.com/
All errors (new ones prefixed by >>):
>> drivers/gpio/gpiolib.c:1109:2: error: no member named 'rwsem' in 'struct raw_notifier_head'
1109 | BLOCKING_INIT_NOTIFIER_HEAD(&gdev->line_state_notifier);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/notifier.h:86:23: note: expanded from macro 'BLOCKING_INIT_NOTIFIER_HEAD'
86 | init_rwsem(&(name)->rwsem); \
| ~~~~~~~~~~~~~~~~~~~~^~~~~~
include/linux/rwsem.h:121:16: note: expanded from macro 'init_rwsem'
121 | __init_rwsem((sem), #sem, &__key); \
| ^~~
1 error generated.
vim +1109 drivers/gpio/gpiolib.c
1044
1045 int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
1046 struct lock_class_key *lock_key,
1047 struct lock_class_key *request_key)
1048 {
1049 struct gpio_device *gdev;
1050 unsigned int desc_index;
1051 int base = 0;
1052 int ret;
1053
1054 /*
1055 * First: allocate and populate the internal stat container, and
1056 * set up the struct device.
1057 */
1058 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
1059 if (!gdev)
1060 return -ENOMEM;
1061
1062 gdev->dev.type = &gpio_dev_type;
1063 gdev->dev.bus = &gpio_bus_type;
1064 gdev->dev.parent = gc->parent;
1065 rcu_assign_pointer(gdev->chip, gc);
1066
1067 gc->gpiodev = gdev;
1068 gpiochip_set_data(gc, data);
1069
1070 device_set_node(&gdev->dev, gpiochip_choose_fwnode(gc));
1071
1072 ret = ida_alloc(&gpio_ida, GFP_KERNEL);
1073 if (ret < 0)
1074 goto err_free_gdev;
1075 gdev->id = ret;
1076
1077 ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
1078 if (ret)
1079 goto err_free_ida;
1080
1081 if (gc->parent && gc->parent->driver)
1082 gdev->owner = gc->parent->driver->owner;
1083 else if (gc->owner)
1084 /* TODO: remove chip->owner */
1085 gdev->owner = gc->owner;
1086 else
1087 gdev->owner = THIS_MODULE;
1088
1089 ret = gpiochip_get_ngpios(gc, &gdev->dev);
1090 if (ret)
1091 goto err_free_dev_name;
1092
1093 gdev->descs = kcalloc(gc->ngpio, sizeof(*gdev->descs), GFP_KERNEL);
1094 if (!gdev->descs) {
1095 ret = -ENOMEM;
1096 goto err_free_dev_name;
1097 }
1098
1099 gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL);
1100 if (!gdev->label) {
1101 ret = -ENOMEM;
1102 goto err_free_descs;
1103 }
1104
1105 gdev->ngpio = gc->ngpio;
1106 gdev->can_sleep = gc->can_sleep;
1107
1108 rwlock_init(&gdev->line_state_lock);
> 1109 BLOCKING_INIT_NOTIFIER_HEAD(&gdev->line_state_notifier);
1110 BLOCKING_INIT_NOTIFIER_HEAD(&gdev->device_notifier);
1111
1112 ret = init_srcu_struct(&gdev->srcu);
1113 if (ret)
1114 goto err_free_label;
1115
1116 ret = init_srcu_struct(&gdev->desc_srcu);
1117 if (ret)
1118 goto err_cleanup_gdev_srcu;
1119
1120
1121 scoped_guard(mutex, &gpio_devices_lock) {
1122 /*
1123 * TODO: this allocates a Linux GPIO number base in the global
1124 * GPIO numberspace for this chip. In the long run we want to
1125 * get *rid* of this numberspace and use only descriptors, but
1126 * it may be a pipe dream. It will not happen before we get rid
1127 * of the sysfs interface anyways.
1128 */
1129 base = gc->base;
1130 if (base < 0) {
1131 base = gpiochip_find_base_unlocked(gc->ngpio);
1132 if (base < 0) {
1133 ret = base;
1134 base = 0;
1135 goto err_cleanup_desc_srcu;
1136 }
1137
1138 /*
1139 * TODO: it should not be necessary to reflect the
1140 * assigned base outside of the GPIO subsystem. Go over
1141 * drivers and see if anyone makes use of this, else
1142 * drop this and assign a poison instead.
1143 */
1144 gc->base = base;
1145 } else {
1146 dev_warn(&gdev->dev,
1147 "Static allocation of GPIO base is deprecated, use dynamic allocation.\n");
1148 }
1149
1150 gdev->base = base;
1151
1152 ret = gpiodev_add_to_list_unlocked(gdev);
1153 if (ret) {
1154 gpiochip_err(gc, "GPIO integer space overlap, cannot add chip\n");
1155 goto err_cleanup_desc_srcu;
1156 }
1157 }
1158
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] gpiolib: fix race condition for gdev->srcu
2025-12-23 8:42 [PATCH] gpiolib: fix race condition for gdev->srcu Paweł Narewski
2025-12-23 20:14 ` kernel test robot
2025-12-24 3:47 ` kernel test robot
@ 2025-12-24 6:21 ` kernel test robot
2025-12-24 8:21 ` Bartosz Golaszewski
2025-12-24 12:20 ` kernel test robot
4 siblings, 0 replies; 6+ messages in thread
From: kernel test robot @ 2025-12-24 6:21 UTC (permalink / raw)
To: Paweł Narewski, linux-gpio
Cc: oe-kbuild-all, linusw, brgl, Paweł Narewski, Jakub Lewalski
Hi Paweł,
kernel test robot noticed the following build errors:
[auto build test ERROR on brgl/gpio/for-next]
[also build test ERROR on next-20251219]
[cannot apply to linus/master v6.16-rc1]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Pawe-Narewski/gpiolib-fix-race-condition-for-gdev-srcu/20251223-165142
base: https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git gpio/for-next
patch link: https://lore.kernel.org/r/20251223084952.1847489-1-pawel.narewski%40nokia.com
patch subject: [PATCH] gpiolib: fix race condition for gdev->srcu
config: x86_64-rhel-9.4-ltp (https://download.01.org/0day-ci/archive/20251224/202512240750.LQnDrYIF-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251224/202512240750.LQnDrYIF-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202512240750.LQnDrYIF-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from include/linux/mm_types.h:13,
from include/linux/mmzone.h:22,
from include/linux/gfp.h:7,
from include/linux/slab.h:16,
from include/linux/resource_ext.h:11,
from include/linux/acpi.h:14,
from drivers/gpio/gpiolib.c:3:
drivers/gpio/gpiolib.c: In function 'gpiochip_add_data_with_key':
>> include/linux/notifier.h:86:35: error: 'struct raw_notifier_head' has no member named 'rwsem'
86 | init_rwsem(&(name)->rwsem); \
| ^~
include/linux/rwsem.h:121:23: note: in definition of macro 'init_rwsem'
121 | __init_rwsem((sem), #sem, &__key); \
| ^~~
drivers/gpio/gpiolib.c:1109:9: note: in expansion of macro 'BLOCKING_INIT_NOTIFIER_HEAD'
1109 | BLOCKING_INIT_NOTIFIER_HEAD(&gdev->line_state_notifier);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
vim +86 include/linux/notifier.h
eabc069401bcf4 Alan Stern 2006-10-04 80
e041c683412d5b Alan Stern 2006-03-27 81 #define ATOMIC_INIT_NOTIFIER_HEAD(name) do { \
e041c683412d5b Alan Stern 2006-03-27 82 spin_lock_init(&(name)->lock); \
e041c683412d5b Alan Stern 2006-03-27 83 (name)->head = NULL; \
e041c683412d5b Alan Stern 2006-03-27 84 } while (0)
e041c683412d5b Alan Stern 2006-03-27 85 #define BLOCKING_INIT_NOTIFIER_HEAD(name) do { \
e041c683412d5b Alan Stern 2006-03-27 @86 init_rwsem(&(name)->rwsem); \
e041c683412d5b Alan Stern 2006-03-27 87 (name)->head = NULL; \
e041c683412d5b Alan Stern 2006-03-27 88 } while (0)
e041c683412d5b Alan Stern 2006-03-27 89 #define RAW_INIT_NOTIFIER_HEAD(name) do { \
e041c683412d5b Alan Stern 2006-03-27 90 (name)->head = NULL; \
e041c683412d5b Alan Stern 2006-03-27 91 } while (0)
e041c683412d5b Alan Stern 2006-03-27 92
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] gpiolib: fix race condition for gdev->srcu
2025-12-23 8:42 [PATCH] gpiolib: fix race condition for gdev->srcu Paweł Narewski
` (2 preceding siblings ...)
2025-12-24 6:21 ` kernel test robot
@ 2025-12-24 8:21 ` Bartosz Golaszewski
2025-12-24 12:20 ` kernel test robot
4 siblings, 0 replies; 6+ messages in thread
From: Bartosz Golaszewski @ 2025-12-24 8:21 UTC (permalink / raw)
To: Paweł Narewski; +Cc: linux-gpio, linusw, Jakub Lewalski
On Tue, Dec 23, 2025 at 9:50 AM Paweł Narewski <pawel.narewski@nokia.com> wrote:
>
> If two drivers were calling gpiochip_add_data_with_key(), one may be
> traversing the srcu-protected list in gpio_name_to_desc(), meanwhile
> other has just added its gdev in gpiodev_add_to_list_unlocked().
> This creates a non-mutexed and non-protected timeframe, when one
> instance is dereferencing and using &gdev->srcu, before the other
> has initialized it, resulting in crash:
>
> [ 4.935481] Unable to handle kernel paging request at virtual address ffff800272bcc000
> [ 4.943396] Mem abort info:
> [ 4.943400] ESR = 0x0000000096000005
> [ 4.943403] EC = 0x25: DABT (current EL), IL = 32 bits
> [ 4.943407] SET = 0, FnV = 0
> [ 4.943410] EA = 0, S1PTW = 0
> [ 4.943413] FSC = 0x05: level 1 translation fault
> [ 4.943416] Data abort info:
> [ 4.943418] ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
> [ 4.946220] CM = 0, WnR = 0, TnD = 0, TagAccess = 0
> [ 4.955261] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
> [ 4.955268] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000038e6c000
> [ 4.961449] [ffff800272bcc000] pgd=0000000000000000
> [ 4.969203] , p4d=1000000039739003
> [ 4.979730] , pud=0000000000000000
> [ 4.980210] phandle (CPU): 0x0000005e, phandle (BE): 0x5e000000 for node "reset"
> [ 4.991736] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
> ...
> [ 5.121359] pc : __srcu_read_lock+0x44/0x98
> [ 5.131091] lr : gpio_name_to_desc+0x60/0x1a0
> [ 5.153671] sp : ffff8000833bb430
> [ 5.298440]
> [ 5.298443] Call trace:
> [ 5.298445] __srcu_read_lock+0x44/0x98
> [ 5.309484] gpio_name_to_desc+0x60/0x1a0
> [ 5.320692] gpiochip_add_data_with_key+0x488/0xf00
> 5.946419] ---[ end trace 0000000000000000 ]---
>
> Move initialization code for gdev fields before it is added to
> gpio_devices, with adjacent initialization code.
> Adjust goto statements to reflect modified order of operations
>
> Fixes: 47d8b4c1d868 ("gpio: add SRCU infrastructure to struct gpio_device")
> Reviewed-by: Jakub Lewalski <jakub.lewalski@nokia.com>
> Signed-off-by: Paweł Narewski <pawel.narewski@nokia.com>
> ---
Good catch, there's indeed an optional call to
gpiochip_set_desc_names() that can race. Though I have no idea how you
tested the fix as it can't possibly build - line_state_notifier is a
raw notifier, not blocking.
Let me send a fixed version.
Bart
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] gpiolib: fix race condition for gdev->srcu
2025-12-23 8:42 [PATCH] gpiolib: fix race condition for gdev->srcu Paweł Narewski
` (3 preceding siblings ...)
2025-12-24 8:21 ` Bartosz Golaszewski
@ 2025-12-24 12:20 ` kernel test robot
4 siblings, 0 replies; 6+ messages in thread
From: kernel test robot @ 2025-12-24 12:20 UTC (permalink / raw)
To: Paweł Narewski, linux-gpio
Cc: llvm, oe-kbuild-all, linusw, brgl, Paweł Narewski,
Jakub Lewalski
Hi Paweł,
kernel test robot noticed the following build errors:
[auto build test ERROR on brgl/gpio/for-next]
[also build test ERROR on linus/master v6.19-rc2 next-20251219]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Pawe-Narewski/gpiolib-fix-race-condition-for-gdev-srcu/20251223-165142
base: https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git gpio/for-next
patch link: https://lore.kernel.org/r/20251223084952.1847489-1-pawel.narewski%40nokia.com
patch subject: [PATCH] gpiolib: fix race condition for gdev->srcu
config: x86_64-kexec (https://download.01.org/0day-ci/archive/20251225/202512250122.ibtipV8L-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251225/202512250122.ibtipV8L-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202512250122.ibtipV8L-lkp@intel.com/
All errors (new ones prefixed by >>):
>> drivers/gpio/gpiolib.c:1109:2: error: no member named 'rwsem' in 'struct raw_notifier_head'
1109 | BLOCKING_INIT_NOTIFIER_HEAD(&gdev->line_state_notifier);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/notifier.h:86:23: note: expanded from macro 'BLOCKING_INIT_NOTIFIER_HEAD'
86 | init_rwsem(&(name)->rwsem); \
| ~~~~~~~~~~~~~~~~~~~~^~~~~~
include/linux/rwsem.h:121:16: note: expanded from macro 'init_rwsem'
121 | __init_rwsem((sem), #sem, &__key); \
| ^~~
1 error generated.
vim +1109 drivers/gpio/gpiolib.c
1044
1045 int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
1046 struct lock_class_key *lock_key,
1047 struct lock_class_key *request_key)
1048 {
1049 struct gpio_device *gdev;
1050 unsigned int desc_index;
1051 int base = 0;
1052 int ret;
1053
1054 /*
1055 * First: allocate and populate the internal stat container, and
1056 * set up the struct device.
1057 */
1058 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
1059 if (!gdev)
1060 return -ENOMEM;
1061
1062 gdev->dev.type = &gpio_dev_type;
1063 gdev->dev.bus = &gpio_bus_type;
1064 gdev->dev.parent = gc->parent;
1065 rcu_assign_pointer(gdev->chip, gc);
1066
1067 gc->gpiodev = gdev;
1068 gpiochip_set_data(gc, data);
1069
1070 device_set_node(&gdev->dev, gpiochip_choose_fwnode(gc));
1071
1072 ret = ida_alloc(&gpio_ida, GFP_KERNEL);
1073 if (ret < 0)
1074 goto err_free_gdev;
1075 gdev->id = ret;
1076
1077 ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
1078 if (ret)
1079 goto err_free_ida;
1080
1081 if (gc->parent && gc->parent->driver)
1082 gdev->owner = gc->parent->driver->owner;
1083 else if (gc->owner)
1084 /* TODO: remove chip->owner */
1085 gdev->owner = gc->owner;
1086 else
1087 gdev->owner = THIS_MODULE;
1088
1089 ret = gpiochip_get_ngpios(gc, &gdev->dev);
1090 if (ret)
1091 goto err_free_dev_name;
1092
1093 gdev->descs = kcalloc(gc->ngpio, sizeof(*gdev->descs), GFP_KERNEL);
1094 if (!gdev->descs) {
1095 ret = -ENOMEM;
1096 goto err_free_dev_name;
1097 }
1098
1099 gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL);
1100 if (!gdev->label) {
1101 ret = -ENOMEM;
1102 goto err_free_descs;
1103 }
1104
1105 gdev->ngpio = gc->ngpio;
1106 gdev->can_sleep = gc->can_sleep;
1107
1108 rwlock_init(&gdev->line_state_lock);
> 1109 BLOCKING_INIT_NOTIFIER_HEAD(&gdev->line_state_notifier);
1110 BLOCKING_INIT_NOTIFIER_HEAD(&gdev->device_notifier);
1111
1112 ret = init_srcu_struct(&gdev->srcu);
1113 if (ret)
1114 goto err_free_label;
1115
1116 ret = init_srcu_struct(&gdev->desc_srcu);
1117 if (ret)
1118 goto err_cleanup_gdev_srcu;
1119
1120
1121 scoped_guard(mutex, &gpio_devices_lock) {
1122 /*
1123 * TODO: this allocates a Linux GPIO number base in the global
1124 * GPIO numberspace for this chip. In the long run we want to
1125 * get *rid* of this numberspace and use only descriptors, but
1126 * it may be a pipe dream. It will not happen before we get rid
1127 * of the sysfs interface anyways.
1128 */
1129 base = gc->base;
1130 if (base < 0) {
1131 base = gpiochip_find_base_unlocked(gc->ngpio);
1132 if (base < 0) {
1133 ret = base;
1134 base = 0;
1135 goto err_cleanup_desc_srcu;
1136 }
1137
1138 /*
1139 * TODO: it should not be necessary to reflect the
1140 * assigned base outside of the GPIO subsystem. Go over
1141 * drivers and see if anyone makes use of this, else
1142 * drop this and assign a poison instead.
1143 */
1144 gc->base = base;
1145 } else {
1146 dev_warn(&gdev->dev,
1147 "Static allocation of GPIO base is deprecated, use dynamic allocation.\n");
1148 }
1149
1150 gdev->base = base;
1151
1152 ret = gpiodev_add_to_list_unlocked(gdev);
1153 if (ret) {
1154 gpiochip_err(gc, "GPIO integer space overlap, cannot add chip\n");
1155 goto err_cleanup_desc_srcu;
1156 }
1157 }
1158
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
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