Benjamin Herrenschmidt <b...@kernel.crashing.org> writes: > On Mon, 2013-05-20 at 09:57 +0530, Aneesh Kumar K.V wrote: >> Michael Neuling <mi...@neuling.org> writes: >> >> > Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com> wrote: >> > >> >> From: "Aneesh Kumar K.V" <aneesh.ku...@linux.vnet.ibm.com> >> >> >> >> We need to use smb_rmb when looking at hpte slot array. Otherwise we could >> >> reorder the hpte_slot array load bfore even we marked the pmd trans huge. >> > >> > Does this need to go back into the stable series? >> > >> >> No the changes are not yet upstream. hpte_slot_array changes are in the >> THP series. I didn't want to post the entire series again with the >> above two patches. > > Note that any patch that adds such a rmb should have a very clear > description of what is the corresponding wmb. It's almost never right to > have one without the other. IE. What is it that you are ordering > against.
Will update the commit message. Some of that smb_wmb() are in the core THP, and the others in ppc64 code. Will update with more info. When we deposit pgtable we use pgtable_trans_huge_deposit that calls related smb_wmb(). When we read pgtable via pgtable_trans_huge_withdraw, core THP code does the related smb_wmb() after setting the right PTE information in the pgtable. -aneesh _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
