From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from na01-by2-obe.outbound.protection.outlook.com (mail-by2on0121.outbound.protection.outlook.com [207.46.100.121]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id A828D1A0CEC for ; Sun, 19 Jul 2015 05:25:16 +1000 (AEST) From: Scott Wood To: CC: Scott Wood Subject: [PATCH 1/2] powerpc/booke64: Move mb() to __set_pte_at() with kernel-addr test Date: Sat, 18 Jul 2015 14:24:57 -0500 Message-ID: <1437247498-6027-1-git-send-email-scottwood@freescale.com> MIME-Version: 1.0 Content-Type: text/plain List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , map_kernel() doesn't catch all places that create kernel PTEs. In particular, vmalloc() calls set_pte_at() directly. This causes a crash when booting a non-SMP kernel on e6500. Move the sync to __set_pte(), to be executed only for kernel addresses. Signed-off-by: Scott Wood --- arch/powerpc/include/asm/pgtable.h | 11 +++++++++++ arch/powerpc/mm/pgtable_64.c | 10 ---------- 2 files changed, 11 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h index 11a3863..0717693 100644 --- a/arch/powerpc/include/asm/pgtable.h +++ b/arch/powerpc/include/asm/pgtable.h @@ -169,6 +169,17 @@ static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr, * cases, and 32-bit non-hash with 32-bit PTEs. */ *ptep = pte; + +#ifdef CONFIG_PPC_BOOK3E_64 + /* + * With hardware tablewalk, a sync is needed to ensure that + * subsequent accesses see the PTE we just wrote. Unlike userspace + * mappings, we can't tolerate spurious faults, so make sure + * the new PTE will be seen the first time. + */ + if (is_kernel_addr(addr)) + mb(); +#endif #endif } diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c index 876232d..e92cb21 100644 --- a/arch/powerpc/mm/pgtable_64.c +++ b/arch/powerpc/mm/pgtable_64.c @@ -149,17 +149,7 @@ int map_kernel_page(unsigned long ea, unsigned long pa, int flags) #endif /* !CONFIG_PPC_MMU_NOHASH */ } -#ifdef CONFIG_PPC_BOOK3E_64 - /* - * With hardware tablewalk, a sync is needed to ensure that - * subsequent accesses see the PTE we just wrote. Unlike userspace - * mappings, we can't tolerate spurious faults, so make sure - * the new PTE will be seen the first time. - */ - mb(); -#else smp_wmb(); -#endif return 0; } -- 2.1.4