Hi all, With the new CONFIG_DMA_API_DEBUG_SG option enabled, I get the following warning (actual value of len varies) during boot on various R-Car Gen3 platforms: renesas_sdhi_internal_dmac ee140000.sd: DMA-API: mapping sg segment longer than device claims to support [len=98304] [max=65536] WARNING: CPU: 0 PID: 24 at lib/dma-debug.c:1301 debug_dma_map_sg+0x228/0x344 Modules linked in: CPU: 0 PID: 24 Comm: kworker/0:2 Tainted: G W 4.18.0-rc1-salvator-x-00669-g26e36f8e84173ce8-dirty #2 Hardware name: Renesas Salvator-X 2nd version board based on r8a77965 (DT) Workqueue: events tmio_mmc_done_work pstate: 60400005 (nZCv daif +PAN -UAO) pc : debug_dma_map_sg+0x228/0x344 lr : debug_dma_map_sg+0x228/0x344 sp : ffffff8009db3c40 x29: ffffff8009db3c40 x28: ffffffc076ec5d00 x27: 0000000000000000 x26: 0000000087654321 x25: 0000000000000000 x24: 0000000000010000 x23: 00000000ffffffff x22: ffffff8008c9a626 x21: ffffff800900f000 x20: ffffffc079ad9100 x19: ffffffc0787d3010 x18: 000000000000000a x17: 0000007f8b45ef28 x16: ffffff800808ec5c x15: 0000000000010000 x14: 74207265676e6f6c x13: 20746e656d676573 x12: 20677320676e6970 x11: 70616d203a495041 x10: 2d414d44203a6473 x9 : 2e30303030343165 x8 : 0000000000000000 x7 : ffffff800814a77c x6 : 0000000000000001 x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffffffffffffffff x2 : ffffff8009036ae0 x1 : b2e67a700e93ba00 x0 : 0000000000000000 Call trace: debug_dma_map_sg+0x228/0x344 renesas_sdhi_internal_dmac_start_dma+0x94/0x1a0 tmio_process_mrq+0x134/0x308 tmio_mmc_done_work+0xe0/0xf0 process_one_work+0x394/0x62c worker_thread+0x21c/0x324 kthread+0x118/0x128 ret_from_fork+0x10/0x18 irq event stamp: 26570 hardirqs last enabled at (26569): [<ffffff800814a840>] vprintk_emit+0x33c/0x3e4 hardirqs last disabled at (26570): [<ffffff80080818cc>] do_debug_exception+0x5c/0x17c softirqs last enabled at (26562): [<ffffff8008081da8>] __do_softirq+0x160/0x4ec softirqs last disabled at (26555): [<ffffff80080eb700>] irq_exit+0xa0/0xfc ---[ end trace ea01d01f16e4e27f ]--- Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds