From nobody Fri May 15 14:53:18 2026 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4gH9DZ68JYz6dQMg for ; Fri, 15 May 2026 14:53:18 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R13" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4gH9DZ5K4Xz46nD for ; Fri, 15 May 2026 14:53:18 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1778856798; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=XzxjeAwRyPqVuEJKNKsnmciZVR+wDuIUPrSLSaFouSs=; b=TbwoKaqHGO/uBCG3wV3dI1H1JaaAX/0D0piJbLxMaMFvgCjYE4Zlu/dvq1LAvaoNFSXIbJ 9xQSiZC19VL/98BgdzSScyNpNaNByt2xQANf4TmyIUQmfDBTPKU53UlS5rgO+lFYEwBEOb 6+sFidmEAo46S/J0NBChDj0BikF19cTbiAkMjgR4KCHwFdnOmH4i6RblNMmhhvbWl0u+R2 sN1ihUmXZ4nobcKIm9owy2VjnyJwSii4ybPMR2oT2KLaFuvxVJ72wpimQUKE+P2Ct52hHj 9a0B8h2aBj7XcNNw0f0VC3d/73jMVz+2d5uuGsZQFgPsr1UgtZ+dMFLG3YcAlA== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1778856798; a=rsa-sha256; cv=none; b=IH05oe5JWp/bK8WRSRQFJ7LFjlBcCEKJnIZ4GVwjgi/9j/kCrxmmqZpZjeae06bl3cD47B o4MmV5JHmwoHT98o6L5/4oS2LXi+GblRSdRtc/xXChQc/8ToPfVde6sl6upbKyZjABcRVU 4wCaKdxL1M31vQEeFtzR+Ki56x/1WXwRbDP8gE+lbY+HLjnxQq0EI8V2cmzwny03uzsHm8 64LjSZYjzU2HfrjcifneQX+tNR9HbKadaoY2bHPm8JgeM4iGg9ZpuT84gfOvabG7WtlaeQ 3lDr2UkeiGAlBKlaS4GxrYiZtSx5p6Bjij4pCYmzqAH4wFCvjDhCHjrZzL7Ztg== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1778856798; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=XzxjeAwRyPqVuEJKNKsnmciZVR+wDuIUPrSLSaFouSs=; b=kc5O+Hs0+Nbt+gv3IIeHqKTWSqFDCi781HHZQ98Mpd7AGkuH9tCb/q2F7UpHZbFzCTQV0v XSMrOfiCPsKXTXcvaeYDbLc0Wta7OH9W7egP22sgYn2bejSgw3iXzkc3WvynRGPLyelqQH ukf6UoklXNz8OLlh4xd0O9qHBTDyvwLFlk5D1M+VJGuJqfA83ht1Tn2DiIqaonySefmz+h unueWsZom7lWPBCvKnLQGkKqva0+Z/0aSUaxdBHtO6Pvlwsi003avzFb5Bi8cjCkRqgTyC C7D/K4ohZPC85OCq3xmM5PqjUOTPmX0UHFMvRfERzjJJf0a8S4TiX+BF7F/g9w== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4gH9DZ4sKmz1RHp for ; Fri, 15 May 2026 14:53:18 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 35e7b by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Fri, 15 May 2026 14:53:18 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: ShengYi Hung Subject: git: 776584319fb4 - main - sound: Fix lock order reversal in dsp_poll() List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: aokblast X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 776584319fb4d66cdb1c2f91bed154dfe6a74e5e Auto-Submitted: auto-generated Date: Fri, 15 May 2026 14:53:18 +0000 Message-Id: <6a07335e.35e7b.6354f4f2@gitrepo.freebsd.org> The branch main has been updated by aokblast: URL: https://cgit.FreeBSD.org/src/commit/?id=776584319fb4d66cdb1c2f91bed154dfe6a74e5e commit 776584319fb4d66cdb1c2f91bed154dfe6a74e5e Author: ShengYi Hung AuthorDate: 2026-05-15 08:43:47 +0000 Commit: ShengYi Hung CommitDate: 2026-05-15 14:52:48 +0000 sound: Fix lock order reversal in dsp_poll() chn_poll() may hold both rdch and wrch channel locks while calling chn_trigger(rdch). chn_trigger() switches the lock order from "channel -> dsp dev" to "dsp dev -> channel" by temporarily dropping the channel lock before acquiring the dsp lock. However, only rdch was unlocked during the transition while wrch remained locked. Since wrch is also a channel lock and witness had already established the lock order requirement: dsp dev -> channel witness reports a lock order reversal when pcm_lock() is acquired while wrch is still held. Avoid holding rdch and wrch simultaneously during chn_trigger() lock-order switching by only keeping the channel locks when needed. The issue can be reliably reproduced by starting pipewire, pipewire-pulse, and pavucontrol. Reviewed by: christos MFC after: 2 weeks Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D57009 --- sys/dev/sound/pcm/dsp.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/sys/dev/sound/pcm/dsp.c b/sys/dev/sound/pcm/dsp.c index 797bfba81023..7bc1decc283b 100644 --- a/sys/dev/sound/pcm/dsp.c +++ b/sys/dev/sound/pcm/dsp.c @@ -1877,24 +1877,25 @@ dsp_poll(struct cdev *i_dev, int events, struct thread *td) ret = 0; - dsp_lock_chans(priv, FREAD | FWRITE); wrch = priv->wrch; rdch = priv->rdch; if (wrch != NULL && !(wrch->flags & CHN_F_DEAD)) { + CHN_LOCK(wrch); e = (events & (POLLOUT | POLLWRNORM)); if (e) ret |= chn_poll(wrch, e, td); + CHN_UNLOCK(wrch); } if (rdch != NULL && !(rdch->flags & CHN_F_DEAD)) { + CHN_LOCK(rdch); e = (events & (POLLIN | POLLRDNORM)); if (e) ret |= chn_poll(rdch, e, td); + CHN_UNLOCK(rdch); } - dsp_unlock_chans(priv, FREAD | FWRITE); - PCM_GIANT_LEAVE(d); return (ret);