30 May
2014
30 May
'14
11:22 a.m.
On Fri, 2014-05-30 at 11:06 +0200, Hans de Goede wrote:
The DMA code in sunxi_mmc.c is broken. mmc_trans_data_by_dma() allocates the dma descriptors on the stack,
Oh dear!
and then exits while the dma transfer is in progress, so the dma engine is reading stack memory which at that point may be re-used. So far we've gotten away with this by luck, but recent u-boot changes have shifted the stack start address by 16 bytes, which combined with dma alignment now exposes this problem.
Since we end up just busy waiting for the dma engine anyway, this commit fixes things by simply removing the dma code, resulting in smaller bug-free code.
Signed-off-by: Hans de Goede hdegoede@redhat.com
Acked-by: Ian Campbell ijc@hellion.org.uk