From: FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx>
parport_pc_probe_port() creates the own 'parport_pc' device if the
device argument is NULL. Then parport_pc_probe_port() doesn't
initialize the dma_mask and coherent_dma_mask of the device and calls
dma_alloc_coherent with it. dma_alloc_coherent fails because
dma_alloc_coherent() doesn't accept the uninitialized dma_mask:
http://lkml.org/lkml/2009/6/16/150
Long ago, X86_32 and X86_64 had the own dma_alloc_coherent
implementations; X86_32 accepted a device having dma_mask that is not
initialized however X86_64 didn't. When we merged them, we chose to
prohibit a device having dma_mask that is not initialized. I think
that it's good to require drivers to set up dma_mask (and
coherent_dma_mask) properly if the drivers want DMA.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx>
Reported-by: Malcom Blaney <malcolm.blaney@xxxxxxxxxxxxx>
Tested-by: Malcom Blaney <malcolm.blaney@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxx
Signed-off-by: Alan Cox <alan@xxxxxxxxxxxxxxx>
---
drivers/parport/parport_pc.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)