Re: virt_to_page/pci_map_page vs. pci_map_single

["Ihar 'Philips' Filipau" <filia@softhome.net>]

Hi!

   Can any-one draw a conclusion?
   Which function should be used in which case?

   So this will be at least reflected in lkml archives ;-)

David S. Miller wrote:
> On Mon, 3 Nov 2003 14:02:57 -0800
> David Mosberger <davidm@napali.hpl.hp.com> wrote:
> 
> 
>>>>>>>On 03 Nov 2003 09:17:59 -0500, Jes Sorensen <jes@wildopensource.com> said:
>>
>>  Jes> Hmmm, my brain has gotten ia64ified ;-) It's basically the normal
>>  Jes> mappings of the kernel, ie. the kernel text/data/bss segments as well
>>  Jes> as anything you do not get back as a dynamic mapping such as
>>  Jes> ioremap/vmalloc/kmap.
>>
>>I don't think it's safe to use virt_to_page() on static kernel
>>addresses (text, data, and bss).  For example, ia64 linux nowadays
>>uses a virtual mapping for the static kernel memory, so it's not part
>>of the identity-mapped segment.
> 
> 
> That's correct and it'll break on sparc64 for similar reasons.
> 
> It's also not safe to do virt_to_page() on kernel stack addresses
> either.
> 


-- 
Ihar 'Philips' Filipau  / with best regards from Saarbruecken.
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