linux-kernel - Re: [Bug 487894] New: sky2 0000:06:00.0: DMA-API: device driver frees DMA memory with different size

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] [day] [month] [year] [list]

Message-ID: <20090402152917.GC4776@amd.com>
Date:	Thu, 2 Apr 2009 17:29:17 +0200
From:	Joerg Roedel <joerg.roedel@....com>
To:	Stephen Hemminger <shemminger@...tta.com>
CC:	FUJITA Tomonori <fujita.tomonori@....ntt.co.jp>, davej@...hat.com,
	tglx@...utronix.de, mingo@...hat.com, hpa@...or.com,
	linux-kernel@...r.kernel.org, x86@...nel.org
Subject: Re: [Bug 487894] New: sky2 0000:06:00.0: DMA-API: device driver
	frees DMA memory with different size

On Thu, Apr 02, 2009 at 08:08:06AM -0700, Stephen Hemminger wrote:
> On Thu, 2 Apr 2009 16:31:42 +0200
> Joerg Roedel <joerg.roedel@....com> wrote:
> > Author: Joerg Roedel <joerg.roedel@....com>
> > Date:   Thu Apr 2 15:55:55 2009 +0200
> > 
> >     x86/dma: unify definition of pci_unmap_addr* and pci_unmap_len macros
> >     
> >     Impact: unification of pci-dma macros and pci_32h removal
> >     
> >     This patch unifies the definition of the pci_unmap_addr*, pci_unmap_len*
> >     and DECLARE_PCI_UNMAP* macros. This makes sense because the pci_unmap
> >     functions are no longer no-ops anymore when the kernel runs with
> >     CONFIG_DMA_API_DEBUG. This also simplifies the port of x86_64 iommu
> >     drivers to 32 bit x86 and let us get rid of pci_32.h.
> >     
> >     Signed-off-by: Joerg Roedel <joerg.roedel@....com>
> 
> Would also like some more comments to explain to the kernel neophytes why
> the 32 bit version is no-op.  Do other arch have same issue?
> 
> 
> Acked-by: Stephen Hemminger <shemminger@...tta.com>

Ok, changed the patch description to

x86/dma: unify definition of pci_unmap_addr* and pci_unmap_len macros

Impact: unification of pci-dma macros and pci_32.h removal

This patch unifies the definition of the pci_unmap_addr*, pci_unmap_len*
and DECLARE_PCI_UNMAP* macros. This makes sense because the pci_unmap
functions are no longer no-ops anymore when the kernel runs with
CONFIG_DMA_API_DEBUG. Without an iommu or DMA_API_DEBUG it is a no-op on 32 bit
because the dma mapping path returns a physical address and therefore the
dma-api implementation has no internal state which needs to be destroyed with
an unmap call.
This unification also simplifies the port of x86_64 iommu drivers to 32 bit x86
and let us get rid of pci_32.h.

Signed-off-by: Joerg Roedel <joerg.roedel@....com>
Acked-by: Stephen Hemminger <shemminger@...tta.com>


Joerg


-- 
           | Advanced Micro Devices GmbH
 Operating | Karl-Hammerschmidt-Str. 34, 85609 Dornach bei München
 System    | 
 Research  | Geschäftsführer: Jochen Polster, Thomas M. McCoy, Giuliano Meroni
 Center    | Sitz: Dornach, Gemeinde Aschheim, Landkreis München
           | Registergericht München, HRB Nr. 43632

--
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/