# Allocate fails with error **URL:** \ **Category:** Support\ **Created:** [January 7, 2025, 11:16pm UTC](https://discuss.pynq.io/t/allocate-fails-with-error/7911 "2025-01-07T23:16:20Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Karthick\_Ramu](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/karthick_ramu/32/6563_2.png) [@Karthick\_Ramu](https://discuss.pynq.io/u/Karthick_Ramu)\ **Post date:** [January 7, 2025, 11:16pm UTC](https://discuss.pynq.io/t/allocate-fails-with-error/7911/1 "2025-01-07T23:16:20Z")
PYNQ Version =3.0.1 Board = Zynq Mini ITX XC7Z045 Code snippet import traceback import numpy as np from pynq import allocate from pynq import Overlay overlays = Overlay(“./pynq/overlays/dma.bit”, download=False) dma = overlays.ADC\_DAC\_DMA input\_buffer = allocate(shape=(5,), dtype=‘u4’) output\_buffer = allocate(shape=(5,), dtype=‘u4’) Error: oot@pynq:/home/xilinx/daffodil-app# python dma.py XRT build version: 2.13.0 Build hash: f5505e402c2ca1ffe45eb6d3a9399b23a0dc8776 Build date: 2022-10-21 17:40:17 Git branch: temp PID: 6450 UID: 0 [Tue Jan 7 17:21:21 2025 GMT] HOST: EXE: /usr/bin/python3.10 [XRT] ERROR: boost::filesystem::directory\_iterator::construct: No such file or directory: “/dev/dri/by-path/” Traceback (most recent call last): File “/home/xilinx/daffodil-app/dma.py”, line 8, in input\_buffer = allocate(shape=(5,), dtype=‘u4’) File “/home/xilinx/daffodil-app/pynq/buffer.py”, line 158, in allocate return target.allocate(shape, dtype, \*\*kwargs) File “/home/xilinx/daffodil-app/pynq/pl\_server/device.py”, line 145, in allocate return self.default\_memory.allocate(shape, dtype, \*\*kwargs) File “/home/xilinx/daffodil-app/pynq/pl\_server/xrt\_device.py”, line 156, in allocate buf = \_xrt\_allocate(shape, dtype, self.device, self.idx, \*\*kwargs) File “/home/xilinx/daffodil-app/pynq/pl\_server/xrt\_device.py”, line 104, in \_xrt\_allocate bo = device.allocate\_bo(size, memidx, cacheable) File “/home/xilinx/daffodil-app/pynq/pl\_server/xrt\_device.py”, line 410, in allocate\_bo raise RuntimeError("Allocate failed: " + str(bo)) RuntimeError: Allocate failed: 4294967274 ---
**Author:** ![marioruiz](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/marioruiz/32/2177_2.png) [@marioruiz](https://discuss.pynq.io/u/marioruiz)\ **Post date:** [January 8, 2025, 12:31pm UTC](https://discuss.pynq.io/t/allocate-fails-with-error/7911/2 "2025-01-08T12:31:39Z")
Hi @Karthick_Ramu, Looks like you built your own PYNQ SD card image for this board. This error could be because the reserved CMA memory is not part of the device tree. If you check the `dmesg` log, you may find more information. Have you tried MMIO access? Mario ---
**Author:** ![Karthick\_Ramu](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/karthick_ramu/32/6563_2.png) [@Karthick\_Ramu](https://discuss.pynq.io/u/Karthick_Ramu)\ **Post date:** [January 8, 2025, 5:09pm UTC](https://discuss.pynq.io/t/allocate-fails-with-error/7911/3 "2025-01-08T17:09:10Z")
My device tree does have DMA in it ADC\_DAC\_DMA\_axi\_dma\_0: dma@4101c000 { #dma-cells = \<1\>; clock-names = “s\_axi\_lite\_aclk”, “m\_axi\_mm2s\_aclk”; clocks = \<&clkc 15\>, \<&clkc 15\>; compatible = “xlnx,axi-dma-7.1”, “xlnx,axi-dma-1.00.a”; interrupt-names = “mm2s\_introut”; interrupt-parent = \<&intc\>; interrupts = \<0 32 4\>; reg = \<0x4101c000 0x1000\>; xlnx,addrwidth = \<0x20\>; xlnx,sg-length-width = \<0xe\>; dma-channel@4101c000 { compatible = “xlnx,axi-dma-mm2s-channel”; dma-channels = \<0x1\>; interrupts = \<0 32 4\>; xlnx,datawidth = \<0x20\>; xlnx,device-id = \<0x0\>; }; No I have not tried MMIO ---
**Author:** ![marioruiz](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/marioruiz/32/2177_2.png) [@marioruiz](https://discuss.pynq.io/u/marioruiz)\ **Post date:** [January 8, 2025, 7:33pm UTC](https://discuss.pynq.io/t/allocate-fails-with-error/7911/4 "2025-01-08T19:33:37Z")
I am referring to the CMA (Contiguous Memory Allocation) entry, not DMA. `allocate` needs CMA. Did you check `dmesg`? ---
**Author:** ![Karthick\_Ramu](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/karthick_ramu/32/6563_2.png) [@Karthick\_Ramu](https://discuss.pynq.io/u/Karthick_Ramu)\ **Post date:** [January 8, 2025, 9:02pm UTC](https://discuss.pynq.io/t/allocate-fails-with-error/7911/5 "2025-01-08T21:02:58Z")
There is no entry for CMA in device tree. Can you show me an example of how it looks? Here is my dmesg entry [0.000000] Memory: 892868K/1048576K available (9216K kernel code, 326K rwdata, 2540K rodata, 1024K init, 294K bss, 24636K reserved, 131072K cma-reserved, 131072K highmem) Also , what does XRT error below mean XRT] ERROR: boost::filesystem::directory\_iterator::construct: No such file or directory: “/dev/dri/by-path/” ---
**Author:** ![marioruiz](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/marioruiz/32/2177_2.png) [@marioruiz](https://discuss.pynq.io/u/marioruiz)\ **Post date:** [January 9, 2025, 11:26am UTC](https://discuss.pynq.io/t/allocate-fails-with-error/7911/6 "2025-01-09T11:26:30Z")
You can find information here: [https://xilinx-wiki.atlassian.net/wiki/spaces/A/pages/18841683/Linux+Reserved+Memory](https://xilinx-wiki.atlassian.net/wiki/spaces/A/pages/18841683/Linux+Reserved+Memory) I will also suggest you check `dmesg` to see if CMA is enabled as it can also be defined in the kernel boot args. > Also , what does XRT error below mean > XRT] ERROR: boost::filesystem::directory\_iterator::construct: No such file or directory: “/dev/dri/by-path/” > [@Pynq Throwing Boost Exception, /dev/dri/by-path/is missing](https://discuss.pynq.io/t/pynq-throwing-boost-exception-dev-dri-by-path-is-missing/4874/2): > > Hi Doug, Could you share your .spec file that you used to generate the image? And what version of PYNQ are you using? The /dev/dri/by-path directory is related to the zocl driver, it is responsible for accelerator memory allocation (kinda like OpenCL), which is why it appears in the path usually associated with graphics cards. My guess is your .spec is either missing the xrt package or there’s some version mismatch between pynq and xrt. Thanks Shawn Does `xbutil examine` show any device found? ---
**Author:** ![Karthick\_Ramu](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/karthick_ramu/32/6563_2.png) [@Karthick\_Ramu](https://discuss.pynq.io/u/Karthick_Ramu)\ **Post date:** [January 9, 2025, 4:29pm UTC](https://discuss.pynq.io/t/allocate-fails-with-error/7911/7 "2025-01-09T16:29:11Z")
System Configuration OS Name : Linux Release : 5.15.19-xilinx-v2022.1 Version : #1 SMP PREEMPT Mon Apr 11 17:52:14 UTC 2022 Machine : armv7l CPU Cores : 2 Memory : 1000 MB Distribution : PynqLinux, based on Ubuntu 22.04 GLIBC : 2.35 Model : unknown XRT Version : 2.13.0 Branch : temp Hash : f5505e402c2ca1ffe45eb6d3a9399b23a0dc8776 Hash Date : 2022-10-21 17:40:17 ZOCL : 2.13.0, f5505e402c2ca1ffe45eb6d3a9399b23a0dc8776 Devices present 0 devices found BDF : Shell Platform UUID Device ID Device Ready\* - Devices that are not ready will have reduced functionality when using XRT tools ---
**Author:** ![Karthick\_Ramu](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/karthick_ramu/32/6563_2.png) [@Karthick\_Ramu](https://discuss.pynq.io/u/Karthick_Ramu)\ **Post date:** [January 9, 2025, 5:23pm UTC](https://discuss.pynq.io/t/allocate-fails-with-error/7911/8 "2025-01-09T17:23:10Z")
XRT is in my .spec file STAGE4\_PACKAGES\_7z045\_daffodil2 := xrt pynq ethernet precached\_metadata XRT and ZOCL has same version. What other compatibility should I check? ---
**Author:** ![Karthick\_Ramu](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/karthick_ramu/32/6563_2.png) [@Karthick\_Ramu](https://discuss.pynq.io/u/Karthick_Ramu)\ **Post date:** [February 12, 2025, 5:48pm UTC](https://discuss.pynq.io/t/allocate-fails-with-error/7911/9 "2025-02-12T17:48:27Z")
I still have this problem. Is there any solution to this.