linux-kernel - Re: [PATCH v8 03/13] xen/arm: if(pfn_valid(pfn)) call native dma

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: <20141110184111.GH25609@e104818-lin.cambridge.arm.com>
Date:	Mon, 10 Nov 2014 18:41:11 +0000
From:	Catalin Marinas <catalin.marinas@....com>
To:	Stefano Stabellini <stefano.stabellini@...citrix.com>
Cc:	"xen-devel@...ts.xensource.com" <xen-devel@...ts.xensource.com>,
	"konrad.wilk@...cle.com" <konrad.wilk@...cle.com>,
	"Ian.Campbell@...rix.com" <Ian.Campbell@...rix.com>,
	"david.vrabel@...rix.com" <david.vrabel@...rix.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH v8 03/13] xen/arm: if(pfn_valid(pfn)) call native dma_ops

On Mon, Nov 10, 2014 at 04:13:55PM +0000, Stefano Stabellini wrote:
>  void xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
>  		size_t size, enum dma_data_direction dir,
> -		struct dma_attrs *attrs);
> +		struct dma_attrs *attrs)
> +{
> +	unsigned long pfn = PFN_DOWN(handle);
> +	/* Dom0 is mapped 1:1, so calling pfn_valid on a foreign mfn will
> +	 * always return false. If the page is local we can safely call the
> +	 * native dma_ops function, otherwise we call the xen specific
> +	 * function. */
> +	if (pfn_valid(pfn)) {
> +		if (__generic_dma_ops(hwdev)->unmap_page)
> +			__generic_dma_ops(hwdev)->unmap_page(hwdev, handle, size, dir, attrs);

Similarly here, do we need the unmap_page check? dma_map_page() does not
do it.

-- 
Catalin
--
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/