debug_dma_assert_idle - snd_hda_intel - cpu touching an active dma mapped cacheline

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WARNING: CPU: 2 PID: 628 at lib/dma-debug.c:593 debug_dma_assert_idle+0x159/0x1d0()
snd_hda_intel 0000:00:07.0: DMA-API: cpu touching an active dma mapped cacheline [cln=0x03074000]
CPU: 2 PID: 628 Comm: lightdm Not tainted 3.15.0-0.rc5.git0.1.fc21.i686+debug #1
Call Trace:
 [<c0ae737d>] dump_stack+0x48/0x60
 [<c04547b2>] warn_slowpath_common+0x82/0xa0
 [<c0754d99>] ? debug_dma_assert_idle+0x159/0x1d0
 [<c0754d99>] ? debug_dma_assert_idle+0x159/0x1d0
 [<c045480e>] warn_slowpath_fmt+0x3e/0x60
 [<c0754d99>] debug_dma_assert_idle+0x159/0x1d0
 [<c058a149>] ? anon_vma_prepare+0x29/0x140
 [<c057e56e>] do_wp_page+0xce/0x890
 [<c0580b72>] handle_mm_fault+0x662/0xb70
 [<c0af3667>] __do_page_fault+0x1a7/0x5d0
 [<c04e1057>] ? SyS_futex+0x97/0x180
 [<c04b1b00>] ? trace_hardirqs_on_caller+0x1c0/0x1e0
 [<c04b1a7c>] ? trace_hardirqs_on_caller+0x13c/0x1e0
 [<c0af3a90>] ? __do_page_fault+0x5d0/0x5d0
 [<c0af3aaa>] do_page_fault+0x1a/0x20
 [<c0af0484>] error_code+0x6c/0x74
---[ end trace b400a64c04aed387 ]---
Mapped at:
 [<c0752e42>] debug_dma_alloc_coherent+0x22/0x70
 [<f80c3e90>] snd_dma_alloc_pages+0x170/0x260 [snd_pcm]
 [<f80c3fe2>] snd_dma_alloc_pages_fallback+0x62/0x90 [snd_pcm]
 [<f80c43b0>] snd_malloc_sgbuf_pages+0xf0/0x211 [snd_pcm]
 [<f80c3f23>] snd_dma_alloc_pages+0x203/0x260 [snd_pcm]


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