From nobody Sun Feb 8 00:26:07 2026 Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.2]) (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 5EF7327380A; Wed, 21 Jan 2026 04:22:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.2 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768969346; cv=none; b=ff8kexwyEiw32jRLQsc5Ele5zFASZBkvNSLTQdpseDDxqeoRG5vcMu/wumDQkMcabcRUtOw+OWGyZoU9ftRHqrNUC8nYnEXFZxtXBd6inYCk+mrC/mHC+upH+B+kw0KDS96NehxtoUbJlsf+malVWKSKogUQZSVgwxZq+2RGg7A= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768969346; c=relaxed/simple; bh=r3LhJeqmIyHYQ48RgTfyTB/lA8q3At5gStd5EXR0/9M=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=FYSsjscX1nxvJvFXiS5v7dCU7VXN1NJyq/9MTuc9vthg8o/VwOWx/F6NGktPcPJhce1jO1YYBgH1iK/NT9CCiB4al/muyrH9nkfIrGA654JX/EKtCKyLPy3LbNE4Q7ubpsbUrGSUT1EGymNhAygVllNgTxd29VHi6BGgck6kNi4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=WVbndEji; arc=none smtp.client-ip=220.197.31.2 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="WVbndEji" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=fS 5fJ55YFcEIupmK8h+jEbbn4Xp6l4seoUgXjOxzdLQ=; b=WVbndEjiL8MJARVHqP PIskxIQ+2q2GldeExf62mp1fIRXpG9e+DPZgbEkpj6Gob2AVRbQ5FvE+SN9AJIne 15G0G02kMOC+MYyFfAZ0vtQyUPeHByN+h09gfhqS9qxlHcwJQ8uXWfx4JpDezxjW v46ZqgRQSSyykWdhA7XPKQsHI= Received: from pek-lpg-core6.wrs.com (unknown []) by gzga-smtp-mtada-g1-1 (Coremail) with SMTP id _____wDnH55pVHBpYLHwGg--.2448S2; Wed, 21 Jan 2026 12:22:02 +0800 (CST) From: Rahul Sharma To: gregkh@linuxfoundation.org, stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Alex Hung , Mario Limonciello , Alex Deucher , Aurabindo Pillai , Rahul Sharma Subject: [PATCH v6.1] drm/amd/display: Check dce_hwseq before dereferencing it Date: Wed, 21 Jan 2026 12:21:58 +0800 Message-Id: <20260121042158.3553167-1-black.hawk@163.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: _____wDnH55pVHBpYLHwGg--.2448S2 X-Coremail-Antispam: 1Uf129KBjvJXoWxJr1fur13Wr1kAw1xZw1xuFg_yoW8CFWUpr n3Gw1rWws7AFyUZa4DJ3W8uFW3uaykJF43GFZFy3Wru3sIyFW0q39Yyan7WryxuF1DZ3Wa qFsxGFWxtF1FkrUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0piGXHJUUUUU= X-CM-SenderInfo: 5eoduy4okd4yi6rwjhhfrp/xtbC3gulP2lwVGsfPQAA3L Content-Type: text/plain; charset="utf-8" From: Alex Hung [ Upstream commit b669507b637eb6b1aaecf347f193efccc65d756e ] [WHAT] hws was checked for null earlier in dce110_blank_stream, indicating hws can be null, and should be checked whenever it is used. Cc: Mario Limonciello Cc: Alex Deucher Reviewed-by: Aurabindo Pillai Signed-off-by: Alex Hung Signed-off-by: Aurabindo Pillai Signed-off-by: Alex Deucher (cherry picked from commit 79db43611ff61280b6de58ce1305e0b2ecf675ad) Cc: stable@vger.kernel.org [ The context change is due to the commit 8e7b3f5435b3 ("drm/amd/display: Add control flag to dc_stream_state to skip eDP BL off/l= ink off") and the commit a8728dbb4ba2 ("drm/amd/display: Refactor edp power control") and the proper adoption is done. ] Signed-off-by: Rahul Sharma --- drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c b/= drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c index 508f5fe26848..c542d2ab9160 100644 --- a/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c +++ b/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c @@ -1233,7 +1233,8 @@ void dce110_blank_stream(struct pipe_ctx *pipe_ctx) struct dce_hwseq *hws =3D link->dc->hwseq; =20 if (link->local_sink && link->local_sink->sink_signal =3D=3D SIGNAL_TYPE_= EDP) { - hws->funcs.edp_backlight_control(link, false); + if (hws) + hws->funcs.edp_backlight_control(link, false); link->dc->hwss.set_abm_immediate_disable(pipe_ctx); } =20 --=20 2.34.1