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authorMauro Carvalho Chehab <mchehab@osg.samsung.com>2015-12-16 15:33:54 -0200
committerMauro Carvalho Chehab <mchehab@osg.samsung.com>2016-01-11 12:19:24 -0200
commitba0dd729bfc09e51af238a630deba70205442afe (patch)
tree7515b8e1427a01b63a00f31698f90024283181ae /drivers/media/media-device.c
parent430a672c83c3e2e9a96c777a874f345c8d21f929 (diff)
[media] media-entity: don't sleep at media_device_register_entity()
media_device_register_entity() is protected by a spin_lock. Calling ida_pre_get() with GFP_KERNEL may put it to sleep, with is a bad idea and causes this warning: [ 8812.397195] BUG: sleeping function called from invalid context at mm/slub.c:1287 [ 8812.397203] in_atomic(): 1, irqs_disabled(): 0, pid: 15179, name: modprobe [ 8812.397207] INFO: lockdep is turned off. [ 8812.397213] CPU: 2 PID: 15179 Comm: modprobe Tainted: G B 4.4.0-rc2+ #41 [ 8812.397218] Hardware name: /NUC5i7RYB, BIOS RYBDWi35.86A.0350.2015.0812.1722 08/12/2015 [ 8812.397222] 0000000000000000 ffff880314c77268 ffffffff818f8ba7 ffff8803b17dde00 [ 8812.397232] ffff880314c77290 ffffffff811c2ee5 ffff8803b17dde00 ffffffff8284dbc9 [ 8812.397241] 0000000000000507 ffff880314c772d0 ffffffff811c30d5 0000000041b58ab3 [ 8812.397250] Call Trace: [ 8812.397258] [<ffffffff818f8ba7>] dump_stack+0x4b/0x64 [ 8812.397265] [<ffffffff811c2ee5>] ___might_sleep+0x245/0x3a0 [ 8812.397270] [<ffffffff811c30d5>] __might_sleep+0x95/0x1a0 [ 8812.397276] [<ffffffff818fd083>] ? ida_pre_get+0x113/0x250 [ 8812.397282] [<ffffffff8153bb77>] kmem_cache_alloc+0x197/0x250 [ 8812.397288] [<ffffffff818fd083>] ida_pre_get+0x113/0x250 [ 8812.397293] [<ffffffff818fd265>] ida_simple_get+0xa5/0x170 [ 8812.397298] [<ffffffff818fd1c0>] ? ida_pre_get+0x250/0x250 [ 8812.397306] [<ffffffffa07382d1>] media_device_register_entity+0x171/0x420 [media] [ 8812.397318] [<ffffffffa129e76f>] v4l2_device_register_subdev+0x34f/0x640 [videodev] [ 8812.397324] [<ffffffffa0768dea>] v4l2_i2c_new_subdev_board+0x12a/0x250 [v4l2_common] [ 8812.397330] [<ffffffffa0768fe7>] v4l2_i2c_new_subdev+0xd7/0x110 [v4l2_common] [ 8812.397337] [<ffffffffa0768f10>] ? v4l2_i2c_new_subdev_board+0x250/0x250 [v4l2_common] [ 8812.397347] [<ffffffffa13d2f76>] au0828_card_analog_fe_setup+0x2e6/0x3f0 [au0828] [ 8812.397352] [<ffffffff814450cc>] ? power_down+0xc4/0xc4 [ 8812.397361] [<ffffffffa13d2c90>] ? au0828_tuner_callback+0x160/0x160 [au0828] [ 8812.397370] [<ffffffffa13d319f>] au0828_card_setup+0x11f/0x340 [au0828] [ 8812.397378] [<ffffffffa13d3080>] ? au0828_card_analog_fe_setup+0x3f0/0x3f0 [au0828] [ 8812.397384] [<ffffffff812a575b>] ? msleep+0x7b/0xc0 [ 8812.397393] [<ffffffffa13d0d79>] au0828_usb_probe+0x679/0xcf0 [au0828] [ 8812.397399] [<ffffffff81d7619d>] usb_probe_interface+0x45d/0x940 [ 8812.397406] [<ffffffff81ca7004>] driver_probe_device+0x454/0xd90 [ 8812.397411] [<ffffffff81ca7940>] ? driver_probe_device+0xd90/0xd90 [ 8812.397417] [<ffffffff81ca7940>] ? driver_probe_device+0xd90/0xd90 [ 8812.397422] [<ffffffff81ca7a61>] __driver_attach+0x121/0x160 [ 8812.397427] [<ffffffff81ca141f>] bus_for_each_dev+0x11f/0x1a0 [ 8812.397433] [<ffffffff81ca1300>] ? subsys_dev_iter_exit+0x10/0x10 [ 8812.397439] [<ffffffff822917d7>] ? _raw_spin_unlock+0x27/0x40 [ 8812.397445] [<ffffffff81ca5d4d>] driver_attach+0x3d/0x50 [ 8812.397450] [<ffffffff81ca5039>] bus_add_driver+0x4c9/0x770 [ 8812.397456] [<ffffffff81ca944c>] driver_register+0x18c/0x3b0 [ 8812.397462] [<ffffffff8124c952>] ? __raw_spin_lock_init+0x32/0x100 [ 8812.397468] [<ffffffff81d71e58>] usb_register_driver+0x1f8/0x440 [ 8812.397473] [<ffffffffa0208000>] ? 0xffffffffa0208000 [ 8812.397481] [<ffffffffa02080b7>] au0828_init+0xb7/0x1000 [au0828] [ 8812.397486] [<ffffffff810021b1>] do_one_initcall+0x141/0x300 [ 8812.397492] [<ffffffff81002070>] ? try_to_run_init_process+0x40/0x40 [ 8812.397497] [<ffffffff8123bbf6>] ? trace_hardirqs_on_caller+0x16/0x590 [ 8812.397502] [<ffffffff815406e6>] ? kasan_unpoison_shadow+0x36/0x50 [ 8812.397507] [<ffffffff815406e6>] ? kasan_unpoison_shadow+0x36/0x50 [ 8812.397512] [<ffffffff815406e6>] ? kasan_unpoison_shadow+0x36/0x50 [ 8812.397517] [<ffffffff815407f7>] ? __asan_register_globals+0x87/0xa0 [ 8812.397524] [<ffffffff814454e5>] do_init_module+0x1d0/0x5a4 [ 8812.397530] [<ffffffff812ed7e8>] load_module+0x6648/0x9d70 [ 8812.397535] [<ffffffff812e4b70>] ? symbol_put_addr+0x50/0x50 [ 8812.397546] [<ffffffff812e71a0>] ? module_frob_arch_sections+0x20/0x20 [ 8812.397552] [<ffffffff8158e950>] ? open_exec+0x50/0x50 [ 8812.397559] [<ffffffff811648db>] ? ns_capable+0x5b/0xd0 [ 8812.397565] [<ffffffff812f1208>] SyS_finit_module+0x108/0x130 [ 8812.397571] [<ffffffff812f1100>] ? SyS_init_module+0x1f0/0x1f0 [ 8812.397576] [<ffffffff81004044>] ? lockdep_sys_exit_thunk+0x12/0x14 [ 8812.397582] [<ffffffff82292236>] entry_SYSCALL_64_fastpath+0x16/0x7a Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Diffstat (limited to 'drivers/media/media-device.c')
-rw-r--r--drivers/media/media-device.c12
1 files changed, 8 insertions, 4 deletions
diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c
index fd67b34dcda3..4d1c13de494b 100644
--- a/drivers/media/media-device.c
+++ b/drivers/media/media-device.c
@@ -537,6 +537,7 @@ int __must_check media_device_register_entity(struct media_device *mdev,
struct media_entity *entity)
{
unsigned int i;
+ int ret;
if (entity->function == MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN ||
entity->function == MEDIA_ENT_F_UNKNOWN)
@@ -551,13 +552,16 @@ int __must_check media_device_register_entity(struct media_device *mdev,
entity->num_links = 0;
entity->num_backlinks = 0;
+ if (!ida_pre_get(&mdev->entity_internal_idx, GFP_KERNEL))
+ return -ENOMEM;
+
spin_lock(&mdev->lock);
- entity->internal_idx = ida_simple_get(&mdev->entity_internal_idx, 1, 0,
- GFP_KERNEL);
- if (entity->internal_idx < 0) {
+ ret = ida_get_new_above(&mdev->entity_internal_idx, 1,
+ &entity->internal_idx);
+ if (ret < 0) {
spin_unlock(&mdev->lock);
- return entity->internal_idx;
+ return ret;
}
mdev->entity_internal_idx_max =

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