Messages in this thread Patch in this message | | | Date | Wed, 12 May 2010 13:53:40 +0200 | From | Sebastian Andrzej Siewior <> | Subject | Re: [BUG] bug when enabling VM DEBUG |
| |
* Catalin Marinas | 2010-05-12 12:10:39 [+0100]:
>> > --- a/drivers/ata/libata-sff.c >> > +++ b/drivers/ata/libata-sff.c >> > @@ -894,7 +894,7 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) >> > do_write); >> > } >> > >> > - if (!do_write) >> > + if (!do_write&& !PageSlab(page)) >> > flush_dcache_page(page); >> >> I would think that check belongs inside flush_dcache_page itself, rather >> than forcing every driver to include it.. > >Sebastian (cc'ed) reported this as well for MIPS. Thx. The patch above looks what I've sent a while ago. Jeff was going to merge it afaik.
>I think it makes sense for this check to be done in the >flush_dcache_page() function.
Why should flush_dcache_page() not flush pages you tell it? From Documentation/cachetlb.txt: | NOTE: This routine need only be called for page cache pages | which can potentially ever be mapped into the address | space of a user process. So for example, VFS layer code | handling vfs symlinks in the page cache need not call | this interface at all.
A page from slab or stack is not going to see the sky of user land and therefore it should not be fed into flush_dcache_page().
Sebastian
| |