From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) (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 76F238F55 for ; Thu, 21 Sep 2023 09:28:13 +0000 (UTC) Received: from [IPV6:2a01:e0a:120:3210:9fdf:789a:7434:5a59] (unknown [IPv6:2a01:e0a:120:3210:9fdf:789a:7434:5a59]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: benjamin.gaignard) by madras.collabora.co.uk (Postfix) with ESMTPSA id 46F3066072F2; Thu, 21 Sep 2023 10:28:11 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1695288491; bh=7cWF6ZvU+KANva5DnNTVmLHFyd+/y6UpOK+LTrLjt9s=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=curIueGoPYgbnIIMKMzX4FKdIZrLZSskm/tPQ1MrKWGQ1y93tb3M5jSjUnbPsahHM U2MdyjWSjFAT/VV6QCT0uXyxh1FJZOlinGEUWNWWbwSq/b1Sz8Zasa/bhKG4UXkGf5 Jn4/dpOqEC1tA1ZKkipKdribhQE9T948aKP00yFARr3Stt8We21FW338M4ECtwpOZO OCNOzd/0r3xoCDgbZEgNz6R8AWtr0c+PyGy2odrqzeUMf0IkbEBqXmOOyJ+p1eZHFK +b/95Y4J6RkWiD6+9BM/2SBEYq3UiewhDMw0o9UuvqFCtw/XsLzZY1UO4HbuxYuE0r QlzoXtwI8IZ6w== Message-ID: <31f298ec-6280-d21b-3d8a-c7bf1c9c0c30@collabora.com> Date: Thu, 21 Sep 2023 11:28:09 +0200 Precedence: bulk X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 Subject: Re: [PATCH v7 45/49] media: core: Add bitmap manage bufs array entries To: Hans Verkuil , mchehab@kernel.org, tfiga@chromium.org, m.szyprowski@samsung.com, ming.qian@nxp.com, ezequiel@vanguardiasur.com.ar, p.zabel@pengutronix.de, gregkh@linuxfoundation.org, nicolas.dufresne@collabora.com Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-staging@lists.linux.dev, kernel@collabora.com References: <20230914133323.198857-1-benjamin.gaignard@collabora.com> <20230914133323.198857-46-benjamin.gaignard@collabora.com> <1142bbb4-b8f1-44ec-962e-9347a231782f@xs4all.nl> <20b6b93e-eef8-3d7b-a3c2-795f220059d4@collabora.com> <470682b4-c14b-4237-bc46-fddfdd085026@xs4all.nl> Content-Language: en-US From: Benjamin Gaignard In-Reply-To: <470682b4-c14b-4237-bc46-fddfdd085026@xs4all.nl> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Le 20/09/2023 à 16:56, Hans Verkuil a écrit : > On 20/09/2023 16:30, Benjamin Gaignard wrote: > > >>>>       num_buffers = min_t(unsigned int, num_buffers, >>>>                   q->max_allowed_buffers - vb2_get_num_buffers(q)); >>>>   -    first_index = vb2_get_num_buffers(q); >>>> +    first_index = bitmap_find_next_zero_area(q->bufs_map, q->max_allowed_buffers, >>>> +                         0, num_buffers, 0); >>>>         if (first_index >= q->max_allowed_buffers) >>>>           return 0; >>>> @@ -675,7 +678,13 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers) >>>>     struct vb2_buffer *vb2_get_buffer(struct vb2_queue *q, unsigned int index) >>>>   { >>>> -    if (index < q->num_buffers) >>>> +    if (!q->bufs_map || !q->bufs) >>>> +        return NULL; >>> I don't think this can ever happen. >> I got kernel crash without them. >> I will keep them. > What is the backtrace? How can this happen? It feels wrong that this can be > called with a vb2_queue that apparently is not properly initialized. I have this log when adding dump_stack() in vb2_get_buffer() if !q->bufs_bitmap: [ 18.924627] Call trace: [ 18.927090] dump_backtrace+0x94/0xec [ 18.930787] show_stack+0x18/0x24 [ 18.934137] dump_stack_lvl+0x48/0x60 [ 18.937833] dump_stack+0x18/0x24 [ 18.941166] __vb2_queue_cancel+0x23c/0x2f0 [ 18.945365] vb2_core_queue_release+0x24/0x6c [ 18.949740] vb2_queue_release+0x10/0x1c [ 18.953677] v4l2_m2m_ctx_release+0x20/0x40 [ 18.957892] hantro_release+0x20/0x54 [ 18.961584] v4l2_release+0x74/0xec [ 18.965110] __fput+0xb4/0x274 [ 18.968205] __fput_sync+0x50/0x5c [ 18.971626] __arm64_sys_close+0x38/0x7c [ 18.975562] invoke_syscall+0x48/0x114 [ 18.979329] el0_svc_common.constprop.0+0xc0/0xe0 [ 18.984068] do_el0_svc+0x1c/0x28 [ 18.987402] el0_svc+0x40/0xe8 [ 18.990470] el0t_64_sync_handler+0x100/0x12c [ 18.994842] el0t_64_sync+0x190/0x194 This happen at boot time when hantro driver is open and close without other actions. > >>>> + >>>> +    return (bitmap_weight(q->bufs_map, q->max_allowed_buffers) > 0); >>> How about: >>> >>>     return vb2_get_num_buffers(q) > 0; >> vb2_get_num_buffers is defined in videobuf2-core.c, I'm not sure that >> an inline function could depend of a module function. > Not a problem. E.g. v4l2-ctrls.h is full of such static inlines. > > Regards, > > Hans >