Re: AW: AW: v4l2_buffer with PBO mapped memory
Hi Laurent, On 11.04.2014 07:56, Thomas Scheuermann wrote: Hi Laurent, On 07.04.2014 01:37, Laurent Pinchart wrote: Hi Thomas, On Friday 04 April 2014 20:01:33 Scheuermann, Mail wrote: Hi Laurent, I've done the following: echo 3 /sys/module/videobuf2_core/parameters/debug and found in /var/log/kern.log after starting my program: [239432.535077] vb2: Buffer 0, plane 0 offset 0x [239432.535080] vb2: Buffer 1, plane 0 offset 0x001c2000 [239432.535082] vb2: Buffer 2, plane 0 offset 0x00384000 [239432.535083] vb2: Allocated 3 buffers, 1 plane(s) each [239432.535085] vb2: qbuf: userspace address for plane 0 changed, reacquiring memory [239432.535087] vb2: qbuf: failed acquiring userspace memory for plane 0 This confirms everything is working properly up to the point where videobuf2- vmalloc fails to acquire the user pointer memory. The problem comes from vb2_vmalloc_get_userptr() in drivers/media/v4l2-core/videobuf2-vmalloc.c. Unfortunately that function lacks debugging. Are you familiar enough with kernel programming to add printk statements there and see where it fails ? I was able to put some debug output in vb2_vmalloc_get_userptr. A call to 'vb2_get_contig_userptr' failed. I will also put some debug code there to get more information. In vb2_get_contig_userptr I saw that the call to 'follow_pfn' failed and returned -22. Do you know what the problem here is? [239432.535088] vb2: qbuf: buffer preparation failed: -22 [239432.535128] vb2: streamoff: not streaming This message is subject to the following terms and conditions: MAIL DISCLAIMERhttp://www.barco.com/en/maildisclaimer -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html This message is subject to the following terms and conditions: MAIL DISCLAIMERhttp://www.barco.com/en/maildisclaimer -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: AW: AW: v4l2_buffer with PBO mapped memory
On 04/15/2014 08:04 AM, Thomas Scheuermann wrote: Hi Laurent, On 11.04.2014 07:56, Thomas Scheuermann wrote: Hi Laurent, On 07.04.2014 01:37, Laurent Pinchart wrote: Hi Thomas, On Friday 04 April 2014 20:01:33 Scheuermann, Mail wrote: Hi Laurent, I've done the following: echo 3 /sys/module/videobuf2_core/parameters/debug and found in /var/log/kern.log after starting my program: [239432.535077] vb2: Buffer 0, plane 0 offset 0x [239432.535080] vb2: Buffer 1, plane 0 offset 0x001c2000 [239432.535082] vb2: Buffer 2, plane 0 offset 0x00384000 [239432.535083] vb2: Allocated 3 buffers, 1 plane(s) each [239432.535085] vb2: qbuf: userspace address for plane 0 changed, reacquiring memory [239432.535087] vb2: qbuf: failed acquiring userspace memory for plane 0 This confirms everything is working properly up to the point where videobuf2- vmalloc fails to acquire the user pointer memory. The problem comes from vb2_vmalloc_get_userptr() in drivers/media/v4l2-core/videobuf2-vmalloc.c. Unfortunately that function lacks debugging. Are you familiar enough with kernel programming to add printk statements there and see where it fails ? I was able to put some debug output in vb2_vmalloc_get_userptr. A call to 'vb2_get_contig_userptr' failed. Unless I am mistaken vb2_get_contig_userptr() requires that the userptr points to physically contiguous memory, but that should not be a requirement for videobuf2-vmalloc. Pawel, any idea why vb2_get_contig_userptr() is used here? Regards, Hans I will also put some debug code there to get more information. In vb2_get_contig_userptr I saw that the call to 'follow_pfn' failed and returned -22. Do you know what the problem here is? [239432.535088] vb2: qbuf: buffer preparation failed: -22 [239432.535128] vb2: streamoff: not streaming This message is subject to the following terms and conditions: MAIL DISCLAIMERhttp://www.barco.com/en/maildisclaimer -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html This message is subject to the following terms and conditions: MAIL DISCLAIMERhttp://www.barco.com/en/maildisclaimer -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: AW: AW: v4l2_buffer with PBO mapped memory
Hi Laurent, On 07.04.2014 01:37, Laurent Pinchart wrote: Hi Thomas, On Friday 04 April 2014 20:01:33 Scheuermann, Mail wrote: Hi Laurent, I've done the following: echo 3 /sys/module/videobuf2_core/parameters/debug and found in /var/log/kern.log after starting my program: [239432.535077] vb2: Buffer 0, plane 0 offset 0x [239432.535080] vb2: Buffer 1, plane 0 offset 0x001c2000 [239432.535082] vb2: Buffer 2, plane 0 offset 0x00384000 [239432.535083] vb2: Allocated 3 buffers, 1 plane(s) each [239432.535085] vb2: qbuf: userspace address for plane 0 changed, reacquiring memory [239432.535087] vb2: qbuf: failed acquiring userspace memory for plane 0 This confirms everything is working properly up to the point where videobuf2- vmalloc fails to acquire the user pointer memory. The problem comes from vb2_vmalloc_get_userptr() in drivers/media/v4l2-core/videobuf2-vmalloc.c. Unfortunately that function lacks debugging. Are you familiar enough with kernel programming to add printk statements there and see where it fails ? I was able to put some debug output in vb2_vmalloc_get_userptr. A call to 'vb2_get_contig_userptr' failed. I will also put some debug code there to get more information. [239432.535088] vb2: qbuf: buffer preparation failed: -22 [239432.535128] vb2: streamoff: not streaming This message is subject to the following terms and conditions: MAIL DISCLAIMERhttp://www.barco.com/en/maildisclaimer -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: AW: AW: v4l2_buffer with PBO mapped memory
Hi Thomas, On Friday 04 April 2014 20:01:33 Scheuermann, Mail wrote: Hi Laurent, I've done the following: echo 3 /sys/module/videobuf2_core/parameters/debug and found in /var/log/kern.log after starting my program: [239432.535077] vb2: Buffer 0, plane 0 offset 0x [239432.535080] vb2: Buffer 1, plane 0 offset 0x001c2000 [239432.535082] vb2: Buffer 2, plane 0 offset 0x00384000 [239432.535083] vb2: Allocated 3 buffers, 1 plane(s) each [239432.535085] vb2: qbuf: userspace address for plane 0 changed, reacquiring memory [239432.535087] vb2: qbuf: failed acquiring userspace memory for plane 0 This confirms everything is working properly up to the point where videobuf2- vmalloc fails to acquire the user pointer memory. The problem comes from vb2_vmalloc_get_userptr() in drivers/media/v4l2-core/videobuf2-vmalloc.c. Unfortunately that function lacks debugging. Are you familiar enough with kernel programming to add printk statements there and see where it fails ? [239432.535088] vb2: qbuf: buffer preparation failed: -22 [239432.535128] vb2: streamoff: not streaming -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
AW: AW: v4l2_buffer with PBO mapped memory
Hi Laurent, I've done the following: echo 3 /sys/module/videobuf2_core/parameters/debug and found in /var/log/kern.log after starting my program: Apr 4 21:53:48 x240 kernel: [239432.535077] vb2: Buffer 0, plane 0 offset 0x Apr 4 21:53:48 x240 kernel: [239432.535080] vb2: Buffer 1, plane 0 offset 0x001c2000 Apr 4 21:53:48 x240 kernel: [239432.535082] vb2: Buffer 2, plane 0 offset 0x00384000 Apr 4 21:53:48 x240 kernel: [239432.535083] vb2: Allocated 3 buffers, 1 plane(s) each Apr 4 21:53:48 x240 kernel: [239432.535085] vb2: qbuf: userspace address for plane 0 changed, reacquiring memory Apr 4 21:53:48 x240 kernel: [239432.535087] vb2: qbuf: failed acquiring userspace memory for plane 0 Apr 4 21:53:48 x240 kernel: [239432.535088] vb2: qbuf: buffer preparation failed: -22 Apr 4 21:53:48 x240 kernel: [239432.535128] vb2: streamoff: not streaming Regards, Thomas Von: Laurent Pinchart [laurent.pinch...@ideasonboard.com] Gesendet: Freitag, 4. April 2014 01:16 An: Scheuermann, Mail Cc: linux-media@vger.kernel.org Betreff: Re: AW: v4l2_buffer with PBO mapped memory Hi Thomas, On Thursday 03 April 2014 16:52:19 Scheuermann, Mail wrote: Hi Laurent, the driver my device uses is the uvcvideo. I have the kernel 3.11.0-18 from Ubuntu 13.10 running. It is built in in a Thinkpad X240 notebook. OK. A bit of debugging will then be needed. Could you set the videobuf2-core debug parameter to 3, retry your test case and send us the kernel log ? -- Regards, Laurent Pinchart This message is subject to the following terms and conditions: MAIL DISCLAIMERhttp://www.barco.com/en/maildisclaimer -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
