From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: [PATCH v3] powerpc: Fix PTE page address mismatch in pgtable ctor/dtor Date: Sun, 08 Dec 2013 07:32:25 +1100 Message-ID: <1386448345.21910.106.camel@pasglop> References: <874n6muuw4.fsf@linux.vnet.ibm.com> <1386425193-24015-1-git-send-email-hong.pham@windriver.com> <1386448079.21910.105.camel@pasglop> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Paul Mackerras , linuxppc-dev , linux-rt-users , linux-stable , "Aneesh Kumar K.V" To: "Hong H. Pham" Return-path: In-Reply-To: <1386448079.21910.105.camel@pasglop> Sender: stable-owner@vger.kernel.org List-Id: linux-rt-users.vger.kernel.org On Sun, 2013-12-08 at 07:27 +1100, Benjamin Herrenschmidt wrote: > On Sat, 2013-12-07 at 09:06 -0500, Hong H. Pham wrote: > > > diff --git a/arch/powerpc/include/asm/pgalloc-32.h b/arch/powerpc/include/asm/pgalloc-32.h > > index 27b2386..842846c 100644 > > --- a/arch/powerpc/include/asm/pgalloc-32.h > > +++ b/arch/powerpc/include/asm/pgalloc-32.h > > @@ -84,10 +84,8 @@ static inline void pgtable_free_tlb(struct mmu_gather *tlb, > > static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table, > > unsigned long address) > > { > > - struct page *page = page_address(table); > > - > > tlb_flush_pgtable(tlb, address); > > - pgtable_page_dtor(page); > > - pgtable_free_tlb(tlb, page, 0); > > + pgtable_page_dtor(table); > > + pgtable_free_tlb(tlb, page_address(table), 0); > > } > > Ok so your description of the problem confused me a bit, but I see that > in the !64K page, pgtable_t is already a struct page so yes, the > page_address() call here is bogus. > > However, I also noticed that in the 64k page case, we don't call the dto > at all. Is that a problem ? Actually we do, just elsewhere... ignore the above. > Also, Aneesh, shouldn't we just fix the disconnect here and have > pgtable_t always be the same type ? The way this is now is confusing > and error prone... > > > #endif /* _ASM_POWERPC_PGALLOC_32_H */ > > diff --git a/arch/powerpc/include/asm/pgalloc-64.h b/arch/powerpc/include/asm/pgalloc-64.h > > index f65e27b..256d6f8 100644 > > --- a/arch/powerpc/include/asm/pgalloc-64.h > > +++ b/arch/powerpc/include/asm/pgalloc-64.h > > @@ -144,11 +144,9 @@ static inline void pgtable_free_tlb(struct mmu_gather *tlb, > > static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table, > > unsigned long address) > > { > > - struct page *page = page_address(table); > > - > > tlb_flush_pgtable(tlb, address); > > - pgtable_page_dtor(page); > > - pgtable_free_tlb(tlb, page, 0); > > + pgtable_page_dtor(table); > > + pgtable_free_tlb(tlb, page_address(table), 0); > > } > > > > #else /* if CONFIG_PPC_64K_PAGES */ > > Ben. > > > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@lists.ozlabs.org > https://lists.ozlabs.org/listinfo/linuxppc-dev