kernel/linux.git/sound/core/seq/seq_fifo.c, branch v6.19.11

ALSA: seq: Fix KCSAN data-race warning at snd_seq_fifo_poll_wait()

2025-09-17T12:14:12+00:00

snd_seq_fifo_poll_wait() evaluates f->cells without locking after poll_wait(), and KCSAN doesn't like it as it appears to be a data-race. Although this doesn't matter much in practice as the value is volatile, it's still better to address it for the mind piece. Wrap it with f->lock spinlock for avoiding the potential data race. Reported-by: syzbot+c3dbc239259940ededba@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=c3dbc239259940ededba Signed-off-by: Takashi Iwai

ALSA: seq: Clean up fifo locking with guard

2025-08-29T09:52:36+00:00

Yet more cleanup, now for seq_fifo.c about its refcount calls; the manual refcount calls (either snd_use_lock_*() or snd_seq_fifo_lock()) are replaced with guard(snd_seq_fifo). Only code refactoring, and no behavior change. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20250827080520.7544-8-tiwai@suse.de

ALSA: seq: fifo: Use guard() for locking

2024-02-28T14:01:21+00:00

We can simplify the code gracefully with new guard() macro and co for automatic cleanup of locks. Only the code refactoring, and no functional changes. Signed-off-by: Takashi Iwai Link: https://lore.kernel.org/r/20240227085306.9764-13-tiwai@suse.de

ALSA: seq: Fix assignment in if condition

2021-06-09T15:30:26+00:00

There are lots of places doing assignments in if condition in ALSA sequencer core, which is a bad coding style that may confuse readers and occasionally lead to bugs. This patch is merely for coding-style fixes, no functional changes. Link: https://lore.kernel.org/r/20210608140540.17885-57-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: seq: Fix potential concurrent access to the deleted pool

2019-08-25T07:31:10+00:00

The input pool of a client might be deleted via the resize ioctl, the the access to it should be covered by the proper locks. Currently the only missing place is the call in snd_seq_ioctl_get_client_pool(), and this patch papers over it. Reported-by: syzbot+4a75454b9ca2777f35c7@syzkaller.appspotmail.com Cc: Signed-off-by: Takashi Iwai

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

2019-05-30T18:26:35+00:00

Based on 1 normalized pattern(s): 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Richard Fontana Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman

ALSA: seq: Remove superfluous irqsave flags

2019-04-09T15:22:46+00:00

spin_lock_irqsave() is used unnecessarily in various places in sequencer core code although it's pretty obvious that the context is sleepable. Remove irqsave and use the plain spin_lock_irq() in such places for simplicity. Signed-off-by: Takashi Iwai

ALSA: seq: Align temporary re-locking with irqsave version

2019-04-09T15:22:46+00:00

In a few places in sequencer core, we temporarily unlock / re-lock the pool spin lock while waiting for the allocation in the blocking mode. There spin_unlock_irq() / spin_lock_irq() pairs are called while initially spin_lock_irqsave() is used (and spin_lock_irqrestore() at the end of the function again). This is likely OK for now, but it's a bit confusing and error-prone. This patch replaces these temporary relocking lines with the irqsave variant to make the lock/unlock sequence more consistently. Signed-off-by: Takashi Iwai

ALSA: seq: More protection for concurrent write and ioctl races

2018-03-08T11:05:37+00:00

This patch is an attempt for further hardening against races between the concurrent write and ioctls. The previous fix d15d662e89fc ("ALSA: seq: Fix racy pool initializations") covered the race of the pool initialization at writer and the pool resize ioctl by the client->ioctl_mutex (CVE-2018-1000004). However, basically this mutex should be applied more widely to the whole write operation for avoiding the unexpected pool operations by another thread. The only change outside snd_seq_write() is the additional mutex argument to helper functions, so that we can unlock / relock the given mutex temporarily during schedule() call for blocking write. Fixes: d15d662e89fc ("ALSA: seq: Fix racy pool initializations") Reported-by: 范龙飞 Reported-by: Nicolai Stange Reviewed-and-tested-by: Nicolai Stange Cc: Signed-off-by: Takashi Iwai

sched/wait: Rename wait_queue_t => wait_queue_entry_t

2017-06-20T10:18:27+00:00

Rename: wait_queue_t => wait_queue_entry_t 'wait_queue_t' was always a slight misnomer: its name implies that it's a "queue", but in reality it's a queue *entry*. The 'real' queue is the wait queue head, which had to carry the name. Start sorting this out by renaming it to 'wait_queue_entry_t'. This also allows the real structure name 'struct __wait_queue' to lose its double underscore and become 'struct wait_queue_entry', which is the more canonical nomenclature for such data types. Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar