From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2F8E73E49C8 for ; Fri, 24 Jul 2026 18:34:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784918081; cv=none; b=L5aKMB7GqxxtJmYHHLF6FYp0vKd98LXNl4M6U4dhzdzKfBcajrS4kD9eXRqbEGTt+BTDCbgy+R6sr6PVyFYqSupSzW25YYiEtMunblT2M4bOhjlgCJVf3+AQzqrFdodiiQ7qj4cz+wYqdGXFk3mfxrxDKIvzaoW8yoiJwr0RHKg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784918081; c=relaxed/simple; bh=oe3KZmk6dmUXOCOVL3hklbailWVV7Uvr3L4MP3uuQkQ=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=CslyNiZbG1GP9/A+YY03mYCKeCmbUUpFtashs8qMZkrn9SSXIVyucBv3vi9HTnmhEciOVuTWfjWWffA2Hj2vKABmjsr0yeKcSSi+TUTI5gDUrK2EmiOxCnasGqM/JfXIuNy6jQYK37eU8Cuv2b3JD6zkI59uNlCVycBKXcFPZwo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BO9JCQuL; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BO9JCQuL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6CAE21F000E9; Fri, 24 Jul 2026 18:34:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784918079; bh=2PNwBExVz2anWXXqfRrCVp5X8IWf9pYpKRyr8ctS4vk=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=BO9JCQuLv2sSaPceSrkOioDonFBKYHQRYeLCNVbkESd+Niuro/tgn1/r9w1TDgwTu vH2Yl8vwhyJGJ+2yrZGC3Q/g0AC8Ocje5jRjxwAkYPDJl3jZ7tenIMLG2UNHDMhAZe /N1wc4sl1l8zUB8JmRPo8rXhnNlRfOfgiiqR2LsmSACXxcVj9kuHi7t1yRGPE8Eil8 4stmP5lirQF8Pr4sp3St1sJWFABmGkXih8k6zGK/7Wqb8GafeUv6OIo94+12v/h23p 3Y9eAR6EAEjjdguk71mfg/Cjdz0QH3x48ADgAvslFMFNnA7nz7MWQ5/OdAd06sG2pI SkpbEjJRzl5bA== From: sashiko-bot@kernel.org Subject: Re: [PATCH v6 16/16] drm/bridge: synopsys: dw-dp: Add audio support Reply-To: sashiko-reviews@lists.linux.dev To: "Sebastian Reichel" Cc: robh@kernel.org, conor+dt@kernel.org, devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org In-Reply-To: <20260724-synopsys-dw-dp-improvements-v6-16-041d99a19c4e@collabora.com> References: <20260724-synopsys-dw-dp-improvements-v6-0-041d99a19c4e@collabora.com> <20260724-synopsys-dw-dp-improvements-v6-16-041d99a19c4e@collabora.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 24 Jul 2026 18:34:38 +0000 Message-Id: <20260724183439.6CAE21F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Thank you for your contribution! Sashiko AI review found 1 potential issue(= s) to consider: - [High] DRM atomic_disable zeroes the SDP slot allocator bitmap without in= validating the audio subsystem's active SDP slot (audio_sdp_nr), causing cr= oss-subsystem races and hardware state corruption. -- --- Patch [16]: [PATCH v6 16/16] drm/bridge: synopsys: dw-dp: Add audio sup= port --- commit 9b3a7d6fa62f20557e06c0ea7d9cc504eddb75d9 Author: Sebastian Reichel drm/bridge: synopsys: dw-dp: Add audio support Implement audio support for the Synopsys DesignWare DisplayPort controller. > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-dp.c b/drivers/gpu/drm/br= idge/synopsys/dw-dp.c > index 44a13b5d62d39..c7d6f63b5e9a1 100644 > --- a/drivers/gpu/drm/bridge/synopsys/dw-dp.c > +++ b/drivers/gpu/drm/bridge/synopsys/dw-dp.c [ ... ] > @@ -1886,6 +1924,212 @@ static void dw_dp_bridge_oob_notify(struct drm_br= idge *bridge, [ ... ] > +static void dw_dp_audio_unprepare(struct drm_bridge *bridge, > + struct drm_connector *connector) > +{ > + struct dw_dp *dp =3D bridge_to_dp(bridge); > + > + if (dp->audio_sdp_nr >=3D 0) { > + dw_dp_clear_sdp(dp, dp->audio_sdp_nr); > + dp->audio_sdp_nr =3D -1; > + } [Severity: High] Does this leave dp->audio_sdp_nr dangling if the display is disabled while audio is active? Looking at dw_dp_bridge_atomic_disable(), the SDP allocation bitmap is bulk-cleared without resetting the audio subsystem's active SDP slot: drivers/gpu/drm/bridge/synopsys/dw-dp.c:dw_dp_bridge_atomic_disable() { ... scoped_guard(mutex, &dp->sdp_lock) bitmap_zero(dp->sdp_reg_bank, SDP_REG_BANK_SIZE); ... } If userspace triggers a display disable, dw_dp_bridge_atomic_disable() zero= es the bitmap without resetting dp->audio_sdp_nr. When the display is re-enabl= ed, dw_dp_bridge_atomic_enable() might allocate that same slot for a video SDP. If userspace later stops the audio stream, dw_dp_audio_unprepare() would see the stale dp->audio_sdp_nr and clear the hardware registers for the newly allocated video SDP. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260724-synopsys-d= w-dp-improvements-v6-0-041d99a19c4e@collabora.com?part=3D16