Re: [PATCH 2/2] parport_pc: set properly the dma_mask for parport_pcdevice

From: Jeff Garzik
Date: Mon Jun 22 2009 - 11:42:02 EST

Alan Cox wrote:
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:

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(-)

Acked-by: Jeff Garzik <jgarzik@xxxxxxxxxx>

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