/* * Copyright (C) 2000 Takashi Iwai * * Routines for control of EMU WaveTable chip * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include #include #include #include #include #include #include #include "emux_voice.h" MODULE_AUTHOR("Takashi Iwai"); MODULE_DESCRIPTION("Routines for control of EMU WaveTable chip"); MODULE_LICENSE("GPL"); /* * create a new hardware dependent device for Emu8000/Emu10k1 */ int snd_emux_new(struct snd_emux **remu) { struct snd_emux *emu; *remu = NULL; emu = kzalloc(sizeof(*emu), GFP_KERNEL); if (emu == NULL) return -ENOMEM; spin_lock_init(&emu->voice_lock); mutex_init(&emu->register_mutex); emu->client = -1; #ifdef CONFIG_SND_SEQUENCER_OSS emu->oss_synth = NULL; #endif emu->max_voices = 0; emu->use_time = 0; setup_timer(&emu->tlist, snd_emux_timer_callback, (unsigned long)emu); emu->timer_active = 0; *remu = emu; return 0; } EXPORT_SYMBOL(snd_emux_new); /* */ static int sf_sample_new(void *private_data, struct snd_sf_sample *sp, struct snd_util_memhdr *hdr, const void __user *buf, long count) { struct snd_emux *emu = private_data; return emu->ops.sample_new(emu, sp, hdr, buf, count); } static int sf_sample_free(void *private_data, struct snd_sf_sample *sp, struct snd_util_memhdr *hdr) { struct snd_emux *emu = private_data; return emu->ops.sample_free(emu, sp, hdr); } static void sf_sample_reset(void *private_data) { struct snd_emux *emu = private_data; emu->ops.sample_reset(emu); } int snd_emux_register(struct snd_emux *emu, struct snd_card *card, int index, char *name) { int err; struct snd_sf_callback sf_cb; if (snd_BUG_ON(!emu->hw || emu->max_voices <= 0)) return -EINVAL; if (snd_BUG_ON(!card || !name)) return -EINVAL; emu->card = card; emu->name = kstrdup(name, GFP_KERNEL); emu->voices = kcalloc(emu->max_voices, sizeof(struct snd_emux_voice), GFP_KERNEL); if (emu->voices == NULL) return -ENOMEM; /* create soundfont list */ memset(&sf_cb, 0, sizeof(sf_cb)); sf_cb.private_data = emu; if (emu->ops.sample_new) sf_cb.sample_new = sf_sample_new; if (emu->ops.sample_free) sf_cb.sample_free = sf_sample_free; if (emu->ops.sample_reset) sf_cb.sample_reset = sf_sample_reset; emu->sflist = snd_sf_new(&sf_cb, emu->memhdr); if (emu->sflist == NULL) return -ENOMEM; if ((err = snd_emux_init_hwdep(emu)) < 0) return err; snd_emux_init_voices(emu); snd_emux_init_seq(emu, card, index); #ifdef CONFIG_SND_SEQUENCER_OSS snd_emux_init_seq_oss(emu); #endif snd_emux_init_virmidi(emu, card); snd_emux_proc_init(emu, card, index); return 0; } EXPORT_SYMBOL(snd_emux_register); /* */ int snd_emux_free(struct snd_emux *emu) { unsigned long flags; if (! emu) return -EINVAL; spin_lock_irqsave(&emu->voice_lock, flags); if (emu->timer_active) del_timer(&emu->tlist); spin_unlock_irqrestore(&emu->voice_lock, flags); snd_emux_proc_free(emu); snd_emux_delete_virmidi(emu); #ifdef CONFIG_SND_SEQUENCER_OSS snd_emux_detach_seq_oss(emu); #endif snd_emux_detach_seq(emu); snd_emux_delete_hwdep(emu); snd_sf_free(emu->sflist); kfree(emu->voices); kfree(emu->name); kfree(emu); return 0; } EXPORT_SYMBOL(snd_emux_free); /* * INIT part */ static int __init alsa_emux_init(void) { return 0; } static void __exit alsa_emux_exit(void) { } module_init(alsa_emux_init) module_exit(alsa_emux_exit) '30'>30space:mode:
authorDouglas Miller <dougmill@linux.vnet.ibm.com>2017-01-28 06:42:20 -0600
committerTejun Heo <tj@kernel.org>2017-01-28 07:49:42 -0500
commit966d2b04e070bc040319aaebfec09e0144dc3341 (patch)
tree4b96156e3d1dd4dfd6039b7c219c9dc4616da52d /sound/spi/Kconfig
parent1b1bc42c1692e9b62756323c675a44cb1a1f9dbd (diff)
percpu-refcount: fix reference leak during percpu-atomic transition
percpu_ref_tryget() and percpu_ref_tryget_live() should return "true" IFF they acquire a reference. But the return value from atomic_long_inc_not_zero() is a long and may have high bits set, e.g. PERCPU_COUNT_BIAS, and the return value of the tryget routines is bool so the reference may actually be acquired but the routines return "false" which results in a reference leak since the caller assumes it does not need to do a corresponding percpu_ref_put(). This was seen when performing CPU hotplug during I/O, as hangs in blk_mq_freeze_queue_wait where percpu_ref_kill (blk_mq_freeze_queue_start) raced with percpu_ref_tryget (blk_mq_timeout_work). Sample stack trace: __switch_to+0x2c0/0x450 __schedule+0x2f8/0x970 schedule+0x48/0xc0 blk_mq_freeze_queue_wait+0x94/0x120 blk_mq_queue_reinit_work+0xb8/0x180 blk_mq_queue_reinit_prepare+0x84/0xa0 cpuhp_invoke_callback+0x17c/0x600 cpuhp_up_callbacks+0x58/0x150 _cpu_up+0xf0/0x1c0 do_cpu_up+0x120/0x150 cpu_subsys_online+0x64/0xe0 device_online+0xb4/0x120 online_store+0xb4/0xc0 dev_attr_store+0x68/0xa0 sysfs_kf_write+0x80/0xb0 kernfs_fop_write+0x17c/0x250 __vfs_write+0x6c/0x1e0 vfs_write+0xd0/0x270 SyS_write+0x6c/0x110 system_call+0x38/0xe0 Examination of the queue showed a single reference (no PERCPU_COUNT_BIAS, and __PERCPU_REF_DEAD, __PERCPU_REF_ATOMIC set) and no requests. However, conditions at the time of the race are count of PERCPU_COUNT_BIAS + 0 and __PERCPU_REF_DEAD and __PERCPU_REF_ATOMIC set. The fix is to make the tryget routines use an actual boolean internally instead of the atomic long result truncated to a int. Fixes: e625305b3907 percpu-refcount: make percpu_ref based on longs instead of ints Link: https://bugzilla.kernel.org/show_bug.cgi?id=190751 Signed-off-by: Douglas Miller <dougmill@linux.vnet.ibm.com> Reviewed-by: Jens Axboe <axboe@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: e625305b3907 ("percpu-refcount: make percpu_ref based on longs instead of ints") Cc: stable@vger.kernel.org # v3.18+
Diffstat (limited to 'sound/spi/Kconfig')