From patchwork Wed Mar 9 23:12:43 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 595739 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 03CAB14033B; Thu, 10 Mar 2016 23:01:01 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1adzGv-0007lI-Hj; Thu, 10 Mar 2016 12:00:53 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1adnKt-0003iD-75 for kernel-team@lists.ubuntu.com; Wed, 09 Mar 2016 23:16:11 +0000 Received: from 1.general.kamal.us.vpn ([10.172.68.52] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1adnKs-0002el-5r; Wed, 09 Mar 2016 23:16:10 +0000 Received: from kamal by fourier with local (Exim 4.86) (envelope-from ) id 1adnKp-00043W-Gd; Wed, 09 Mar 2016 15:16:07 -0800 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.13.y-ckt 036/138] drivers/scsi/sg.c: mark VMA as VM_IO to prevent migration Date: Wed, 9 Mar 2016 15:12:43 -0800 Message-Id: <1457565265-15195-37-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1457565265-15195-1-git-send-email-kamal@canonical.com> References: <1457565265-15195-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 X-Mailman-Approved-At: Thu, 10 Mar 2016 12:00:52 +0000 Cc: Andrew Morton , Kamal Mostafa , Doug Gilbert , Hugh Dickins , James Bottomley , Kostya Serebryany , syzkaller , Alexander Potapenko , David Rientjes , Sasha Levin , Naoya Horiguchi , Linus Torvalds , Shiraz Hashim , "Kirill A . Shutemov" X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.13.11-ckt36 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: "Kirill A. Shutemov" commit 461c7fa126794157484dca48e88effa4963e3af3 upstream. Reduced testcase: #include #include #include #include #define SIZE 0x2000 int main() { int fd; void *p; fd = open("/dev/sg0", O_RDWR); p = mmap(NULL, SIZE, PROT_EXEC, MAP_PRIVATE | MAP_LOCKED, fd, 0); mbind(p, SIZE, 0, NULL, 0, MPOL_MF_MOVE); return 0; } We shouldn't try to migrate pages in sg VMA as we don't have a way to update Sg_scatter_hold::pages accordingly from mm core. Let's mark the VMA as VM_IO to indicate to mm core that the VMA is not migratable. Signed-off-by: Kirill A. Shutemov Reported-by: Dmitry Vyukov Acked-by: Vlastimil Babka Cc: Doug Gilbert Cc: David Rientjes Cc: Naoya Horiguchi Cc: "Kirill A. Shutemov" Cc: Shiraz Hashim Cc: Hugh Dickins Cc: Sasha Levin Cc: syzkaller Cc: Kostya Serebryany Cc: Alexander Potapenko Cc: James Bottomley Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Kamal Mostafa --- drivers/scsi/sg.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 721d839..0be16bf 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -1258,7 +1258,7 @@ sg_mmap(struct file *filp, struct vm_area_struct *vma) } sfp->mmap_called = 1; - vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; + vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP; vma->vm_private_data = sfp; vma->vm_ops = &sg_mmap_vm_ops; return 0;