linux-kernel - Re: dma_alloc_coherent() on PPC32: physical addresses above 2G possible?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <4883913F.9040706@s5r6.in-berlin.de>
Date:	Sun, 20 Jul 2008 21:25:51 +0200
From:	Stefan Richter <stefanr@...6.in-berlin.de>
To:	Arjan van de Ven <arjan@...radead.org>
CC:	linuxppc-dev@...abs.org, linux-kernel@...r.kernel.org
Subject: Re: dma_alloc_coherent() on PPC32: physical addresses above 2G possible?

Arjan van de Ven wrote:
> On Sun, 20 Jul 2008 20:36:23 +0200
> Stefan Richter <stefanr@...6.in-berlin.de> wrote:
> 
>> PS:  I don't want to set the DMA mask of this device to
>> DMA_31BIT_MASK because that would be detrimental to other functions
>> of the device. It's a TI TSB43AB22A FireWire controller.
> 
> Hi,
> 
> just want to mention that you can set the coherent mask separately from
> the generic mask... is that sufficient for your load?
> (you can even set it just for this allocation..)

Hmm.  Would that be done this way?
During probe:

	if (chip_is_tsb43ab22a) {
		if (dma_supported(dev, DMA_31BIT_MASK))
			chip->needs_dma_mask_workaround = 1;
		else
			chip->needs_some_other_workaround = 1;
	}

Later on:

	if (dev->needs_dma_mask_workaround)
		pci_set_consistent_dma_mask(pdev, DMA_31BIT_MASK);
	allocate_something_special;
	if (dev->needs_dma_mask_workaround)
		pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);

Or is there a variant of dma_alloc_coherent() which directly accepts a
mask argument?
-- 
Stefan Richter
-=====-==--- -=== =-=--
http://arcgraph.de/sr/
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/