Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933448AbaKRO40 (ORCPT ); Tue, 18 Nov 2014 09:56:26 -0500 Received: from cantor2.suse.de ([195.135.220.15]:57226 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932142AbaKROJv (ORCPT ); Tue, 18 Nov 2014 09:09:51 -0500 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Frank Schaefer , Mauro Carvalho Chehab , Jiri Slaby Subject: [PATCH 3.12 099/206] media: em28xx-v4l: give back all active video buffers to the vb2 core properly on streaming stop Date: Tue, 18 Nov 2014 15:07:34 +0100 Message-Id: X-Mailer: git-send-email 2.1.3 In-Reply-To: <28f04bcc068a44c5641c727883947960fb8dcbd5.1416319692.git.jslaby@suse.cz> References: <28f04bcc068a44c5641c727883947960fb8dcbd5.1416319692.git.jslaby@suse.cz> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Frank Schaefer 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 627530c32a43283474e9dd3e954519410ffa033a upstream. When a new video frame is started, the driver takes the next video buffer from the list of active buffers and moves it to dev->usb_ctl.vid_buf / dev->usb_ctl.vbi_buf for further processing. On streaming stop we currently only give back the pending buffers from the list but not the ones which are currently processed. This causes the following warning from the vb2 core since kernel 3.15: ... ------------[ cut here ]------------ WARNING: CPU: 1 PID: 2284 at drivers/media/v4l2-core/videobuf2-core.c:2115 __vb2_queue_cancel+0xed/0x150 [videobuf2_core]() [...] Call Trace: [] dump_stack+0x48/0x69 [] warn_slowpath_common+0x79/0x90 [] ? __vb2_queue_cancel+0xed/0x150 [videobuf2_core] [] ? __vb2_queue_cancel+0xed/0x150 [videobuf2_core] [] warn_slowpath_null+0x1d/0x20 [] __vb2_queue_cancel+0xed/0x150 [videobuf2_core] [] vb2_internal_streamoff+0x35/0x90 [videobuf2_core] [] vb2_streamoff+0x35/0x60 [videobuf2_core] [] vb2_ioctl_streamoff+0x37/0x40 [videobuf2_core] [] v4l_streamoff+0x15/0x20 [videodev] [] __video_do_ioctl+0x23d/0x2d0 [videodev] [] ? video_ioctl2+0x20/0x20 [videodev] [] video_usercopy+0x203/0x5a0 [videodev] [] ? video_ioctl2+0x20/0x20 [videodev] [] ? fsnotify+0x1e7/0x2b0 [] video_ioctl2+0x12/0x20 [videodev] [] ? video_ioctl2+0x20/0x20 [videodev] [] v4l2_ioctl+0xee/0x130 [videodev] [] ? v4l2_open+0xf0/0xf0 [videodev] [] do_vfs_ioctl+0x2e2/0x4d0 [] ? vfs_write+0x13c/0x1c0 [] ? vfs_writev+0x2f/0x50 [] SyS_ioctl+0x58/0x80 [] sysenter_do_call+0x12/0x12 ---[ end trace 5545f934409f13f4 ]--- ... Many thanks to Hans Verkuil, whose recently added check in the vb2 core unveiled this long standing issue and who has investigated it further. Signed-off-by: Frank Schäfer Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Jiri Slaby --- drivers/media/usb/em28xx/em28xx-video.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/media/usb/em28xx/em28xx-video.c b/drivers/media/usb/em28xx/em28xx-video.c index 9d103344f34a..81b21d937201 100644 --- a/drivers/media/usb/em28xx/em28xx-video.c +++ b/drivers/media/usb/em28xx/em28xx-video.c @@ -695,13 +695,16 @@ static int em28xx_stop_streaming(struct vb2_queue *vq) } spin_lock_irqsave(&dev->slock, flags); + if (dev->usb_ctl.vid_buf != NULL) { + vb2_buffer_done(&dev->usb_ctl.vid_buf->vb, VB2_BUF_STATE_ERROR); + dev->usb_ctl.vid_buf = NULL; + } while (!list_empty(&vidq->active)) { struct em28xx_buffer *buf; buf = list_entry(vidq->active.next, struct em28xx_buffer, list); list_del(&buf->list); vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR); } - dev->usb_ctl.vid_buf = NULL; spin_unlock_irqrestore(&dev->slock, flags); return 0; @@ -723,13 +726,16 @@ int em28xx_stop_vbi_streaming(struct vb2_queue *vq) } spin_lock_irqsave(&dev->slock, flags); + if (dev->usb_ctl.vbi_buf != NULL) { + vb2_buffer_done(&dev->usb_ctl.vbi_buf->vb, VB2_BUF_STATE_ERROR); + dev->usb_ctl.vbi_buf = NULL; + } while (!list_empty(&vbiq->active)) { struct em28xx_buffer *buf; buf = list_entry(vbiq->active.next, struct em28xx_buffer, list); list_del(&buf->list); vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR); } - dev->usb_ctl.vbi_buf = NULL; spin_unlock_irqrestore(&dev->slock, flags); return 0; -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/