Re: [PATCH/RFC v3 net] ravb: unmap descriptors when freeing rings
From: Simon Horman <horms@verge.net.au>
Date: 2017-02-13 12:09:19
Also in:
linux-renesas-soc
On Fri, Feb 10, 2017 at 02:52:50PM +0100, Geert Uytterhoeven wrote:
On Wed, Jan 25, 2017 at 5:18 PM, Sergei Shtylyov [off-list ref] wrote:quoted
On 01/24/2017 09:21 PM, Simon Horman wrote:quoted
From: Kazuya Mizuguchi <redacted> "swiotlb buffer is full" errors occur after repeated initialisation of a device - f.e. suspend/resume or ip link set up/down. This is because memory mapped using dma_map_single() in ravb_ring_format() and ravb_start_xmit() is not released. Resolve this problem by unmapping descriptors when freeing rings.Could you look into the sh_eth driver which seems to have the same issue?Indeed, after a few suspend/resume cycles on r8a7791/koelsch: WARNING: CPU: 1 PID: 1699 at lib/dma-debug.c:517 add_dma_entry+0xfc/0x148 DMA-API: exceeded 7 overlapping mappings of cacheline 0x0000000001a827e3
Thanks for confirming that. It matches my expectation after reading of the sh_eth code.