b6e436b263
There are several DMA related interrupts which wake up the dma_waitq. The udma routines use this queue while they wait for their transfer to complete. When woken, the udma routine will check the IVTV_F_I_UDMA_PENDING & IVTV_F_I_UDMA flags to see if the transfer is still queued or has finished. However, a small window exists between the IVTV_F_I_UDMA_PENDING flag being cleared and the IVTV_F_I_UDMA flag being set. Given that the completion of an unrelated DMA transfer may wake up the udma routine, it's possible for this check to fail and the udma routine will start unmapping pages when the transfer has only just started. The result of this is unpredictable. This fix simply delays the clearing of the IVTV_F_I_UDMA_PENDING flag until after IVTV_F_I_UDMA has been set. Signed-off-by: Ian Armstrong <ian@iarmst.demon.co.uk> Signed-off-by: Andy Walls <awalls@radix.net> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com> |
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| common | ||
| dvb | ||
| IR | ||
| radio | ||
| video | ||
| Kconfig | ||
| Makefile | ||