Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932162AbbDMJ4w (ORCPT ); Mon, 13 Apr 2015 05:56:52 -0400 Received: from e06smtp10.uk.ibm.com ([195.75.94.106]:48319 "EHLO e06smtp10.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753597AbbDMJ4s (ORCPT ); Mon, 13 Apr 2015 05:56:48 -0400 From: Laurent Dufour 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 Subject: [RESEND PATCH v3 2/2] powerpc/mm: Tracking vDSO remap Date: Mon, 13 Apr 2015 11:56:28 +0200 Message-Id: <61ceefa2992db9e77640b0d9ac29a128af91241f.1428916945.git.ldufour@linux.vnet.ibm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: References: In-Reply-To: References: X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15041309-0041-0000-0000-000003E51395 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2259 Lines: 74 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/mmu_context.h | 36 +++++++++++++++++++++++++++++++++- 1 file changed, 35 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h index 73382eba02dc..7d315c1898d4 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 +108,40 @@ 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) +{ +} + +#define __HAVE_ARCH_REMAP +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; +} + #endif /* __KERNEL__ */ #endif /* __ASM_POWERPC_MMU_CONTEXT_H */ -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/