From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f181.google.com (mail-wi0-f181.google.com [209.85.212.181]) by kanga.kvack.org (Postfix) with ESMTP id 820076B0070 for ; Wed, 15 Apr 2015 10:17:12 -0400 (EDT) Received: by wiax7 with SMTP id x7so113165580wia.0 for ; Wed, 15 Apr 2015 07:17:12 -0700 (PDT) Received: from e06smtp10.uk.ibm.com (e06smtp10.uk.ibm.com. [195.75.94.106]) by mx.google.com with ESMTPS id e1si8395000wja.52.2015.04.15.07.17.09 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 15 Apr 2015 07:17:10 -0700 (PDT) Received: from /spool/local by e06smtp10.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 15 Apr 2015 15:17:09 +0100 Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by d06dlp03.portsmouth.uk.ibm.com (Postfix) with ESMTP id 7E3611B08072 for ; Wed, 15 Apr 2015 15:17:41 +0100 (BST) Received: from d06av11.portsmouth.uk.ibm.com (d06av11.portsmouth.uk.ibm.com [9.149.37.252]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t3FEH7xX9306508 for ; Wed, 15 Apr 2015 14:17:07 GMT Received: from d06av11.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av11.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t3FEH67D018343 for ; Wed, 15 Apr 2015 08:17:07 -0600 From: Laurent Dufour Subject: [PATCH v5 3/3] powerpc/mm: Tracking vDSO remap Date: Wed, 15 Apr 2015 16:16:58 +0200 Message-Id: <29c21a607c8083626e3ce9f4a19cb00b0205dbaa.1429104776.git.ldufour@linux.vnet.ibm.com> In-Reply-To: References: In-Reply-To: References: <20150414123853.a3e61b7fa95b6c634e0fcce0@linux-foundation.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , "Kirill A. Shutemov" , Hugh Dickins , Rik van Riel , Mel Gorman , Pavel Emelyanov , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Ingo Molnar , linuxppc-dev@lists.ozlabs.org Cc: cov@codeaurora.org, criu@openvz.org Some processes (CRIU) are moving the vDSO area using the mremap system call. As a consequence the kernel reference to the vDSO base address is no more valid and the signal return frame built once the vDSO has been moved is not pointing to the new sigreturn address. This patch handles vDSO remapping and unmapping. Signed-off-by: Laurent Dufour Reviewed-by: Ingo Molnar --- arch/powerpc/include/asm/mm-arch-hooks.h | 13 +++++++++++++ arch/powerpc/include/asm/mmu_context.h | 23 ++++++++++++++++++++++- 2 files changed, 35 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/mm-arch-hooks.h b/arch/powerpc/include/asm/mm-arch-hooks.h index 63091a19de9f..f2a2da895897 100644 --- a/arch/powerpc/include/asm/mm-arch-hooks.h +++ b/arch/powerpc/include/asm/mm-arch-hooks.h @@ -12,4 +12,17 @@ #ifndef _ASM_POWERPC_MM_ARCH_HOOKS_H #define _ASM_POWERPC_MM_ARCH_HOOKS_H +static inline void arch_remap(struct mm_struct *mm, + unsigned long old_start, unsigned long old_end, + unsigned long new_start, unsigned long new_end) +{ + /* + * mremap() doesn't allow moving multiple vmas so we can limit the + * check to old_start == vdso_base. + */ + if (old_start == mm->context.vdso_base) + mm->context.vdso_base = new_start; +} +#define arch_remap arch_remap + #endif /* _ASM_POWERPC_MM_ARCH_HOOKS_H */ diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h index 73382eba02dc..825cb232eab6 100644 --- a/arch/powerpc/include/asm/mmu_context.h +++ b/arch/powerpc/include/asm/mmu_context.h @@ -8,7 +8,6 @@ #include #include #include -#include #include /* @@ -109,5 +108,27 @@ static inline void enter_lazy_tlb(struct mm_struct *mm, #endif } +static inline void arch_dup_mmap(struct mm_struct *oldmm, + struct mm_struct *mm) +{ +} + +static inline void arch_exit_mmap(struct mm_struct *mm) +{ +} + +static inline void arch_unmap(struct mm_struct *mm, + struct vm_area_struct *vma, + unsigned long start, unsigned long end) +{ + if (start <= mm->context.vdso_base && mm->context.vdso_base < end) + mm->context.vdso_base = 0; +} + +static inline void arch_bprm_mm_init(struct mm_struct *mm, + struct vm_area_struct *vma) +{ +} + #endif /* __KERNEL__ */ #endif /* __ASM_POWERPC_MMU_CONTEXT_H */ -- 1.9.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org