linux-kernel - Microblaze, DMA and cache: Lack of sync functions?

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-next>] [day] [month] [year] [list]

Date:	Sat, 13 Aug 2011 13:12:00 +0300
From:	Eli Billauer <eli@...lauer.co.il>
To:	LKML <linux-kernel@...r.kernel.org>
Subject: Microblaze, DMA and cache: Lack of sync functions?

Hello,

Before I make a needless hack, please correct me if I'm wrong: in 
arch/microblaze/kernel/dma.c, the sync_single_for_cpu, 
sync_single_for_device and friends are not set in the dma_direct_ops 
structure (and not implemented), so calls from drivers to the 
corresponding functions will do nothing. Since the Microblaze cache 
doesn't update automatically on DMA operations, this looks like a bug to 
me: The driver thinks the cache has been flushed or updated, but it 
actually hasn't.

Map and unmap methods are indeed implemented and registered, and they 
both call an internal function to sync the cache. So why are there no 
sync functions?

To hack or not to hack?

   Eli

-- 
Web: http://www.billauer.co.il

--
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/