From nobody Mon Apr 6 23:07:09 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B16EEECAAD3 for ; Thu, 1 Sep 2022 17:36:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234920AbiIARgz (ORCPT ); Thu, 1 Sep 2022 13:36:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51864 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234695AbiIARfv (ORCPT ); Thu, 1 Sep 2022 13:35:51 -0400 Received: from mail-pj1-x1049.google.com (mail-pj1-x1049.google.com [IPv6:2607:f8b0:4864:20::1049]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4217567C82 for ; Thu, 1 Sep 2022 10:35:46 -0700 (PDT) Received: by mail-pj1-x1049.google.com with SMTP id f16-20020a17090a4a9000b001f234757bbbso7906905pjh.6 for ; Thu, 01 Sep 2022 10:35:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date; bh=f3HBd//8MTEjGtUKjIJ6VlUao66B8ATA87dRitXKN6o=; b=osN5P5u2gNPNqCUBvTG+Zi66behXZjVMeiTYran173d3bK7x/C4pNezlQHCFvkYQk7 qOQqzQeCFbXQDX9e+QRzeVBdZKr22OFya12CKF/BNucIJ15gJeM6CJ6xJtVhkJ86JMIW z0BrEcSFGRuuGzZ7AIa/XsKdDh+JkQT9DWUmeCCWJ5VsR1VGSIBZmgZx0ZCJYBHl+XPj GoCI/RFibFsonWSqgiZwplWva8pXUgT5urz+18AucAe/seeiQYlfr5LWvUC2qg96tyno slrVqaBJlR1Fm38ZmASWvylf1J3rbhYM8n7OsiK4uazMHDS7+qFeKWZULOPVqfmGOKH5 n3ag== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date; bh=f3HBd//8MTEjGtUKjIJ6VlUao66B8ATA87dRitXKN6o=; b=4kf6+oiwsHYjVM2VEdhZ+BOF4k3Cz1fTofqAa30nVQAAG+76qqT0pWwH1dLj9QDVum /PqES7QqW+nfGInP1VFX1xmx8tsnzmVEPe3tukXRQyvIAKQFk2oBV5N4WUS+2IIpqNWc G0K6qHV7gGlGRIfYNqzC9/O0tpXfTN8K8vyJFZjPCmXyfr6grQUiszlW/1P8D2WGUi9J FW0CB8HK4AII3uuu7zsuwwdxzcPdHMZIbgbYGRJb8sVu3IAeZ4v4mFStM22gIVkTBJQq U/6zx36E3R4XRacL7bTBm+eNL97/7TeQHhqJt0CRjnsenJUzJG6j8swPSc5zuvZIZFCL SIfw== X-Gm-Message-State: ACgBeo20KIbojXmnWkNa1VWvQFSeXj7u2wQFWZjOUrUEpty56JF+i47J LZov4+9KEXRRnfykkBWo3i1L1WtdCS8= X-Google-Smtp-Source: AA6agR6Q3wPydZYjoco/mRjMkhmNWxJo3Xdi/ebZ3ovzfa+ebF5iWZWFhqHdfMvubIqW+qGVzpwNqTYAd9U= X-Received: from surenb-desktop.mtv.corp.google.com ([2620:15c:211:200:1bfc:e7ee:6530:4449]) (user=surenb job=sendgmr) by 2002:a17:903:2351:b0:175:58b8:cdef with SMTP id c17-20020a170903235100b0017558b8cdefmr4890777plh.30.1662053745409; Thu, 01 Sep 2022 10:35:45 -0700 (PDT) Date: Thu, 1 Sep 2022 10:34:57 -0700 In-Reply-To: <20220901173516.702122-1-surenb@google.com> Mime-Version: 1.0 References: <20220901173516.702122-1-surenb@google.com> X-Mailer: git-send-email 2.37.2.789.g6183377224-goog Message-ID: <20220901173516.702122-10-surenb@google.com> Subject: [RFC PATCH RESEND 09/28] mm/mempolicy: mark VMA as locked when changing protection policy From: Suren Baghdasaryan To: akpm@linux-foundation.org Cc: michel@lespinasse.org, jglisse@google.com, mhocko@suse.com, vbabka@suse.cz, hannes@cmpxchg.org, mgorman@suse.de, dave@stgolabs.net, willy@infradead.org, liam.howlett@oracle.com, peterz@infradead.org, ldufour@linux.ibm.com, laurent.dufour@fr.ibm.com, paulmck@kernel.org, luto@kernel.org, songliubraving@fb.com, peterx@redhat.com, david@redhat.com, dhowells@redhat.com, hughd@google.com, bigeasy@linutronix.de, kent.overstreet@linux.dev, rientjes@google.com, axelrasmussen@google.com, joelaf@google.com, minchan@google.com, surenb@google.com, kernel-team@android.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, x86@kernel.org, linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Protect VMA from concurrent page fault handler while performing VMA protection policy changes. Signed-off-by: Suren Baghdasaryan --- mm/mempolicy.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index b73d3248d976..6be1e5c75556 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -383,8 +383,10 @@ void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *= new) struct vm_area_struct *vma; =20 mmap_write_lock(mm); - for (vma =3D mm->mmap; vma; vma =3D vma->vm_next) + for (vma =3D mm->mmap; vma; vma =3D vma->vm_next) { + vma_mark_locked(vma); mpol_rebind_policy(vma->vm_policy, new); + } mmap_write_unlock(mm); } =20 @@ -632,6 +634,7 @@ unsigned long change_prot_numa(struct vm_area_struct *v= ma, struct mmu_gather tlb; int nr_updated; =20 + vma_mark_locked(vma); tlb_gather_mmu(&tlb, vma->vm_mm); =20 nr_updated =3D change_protection(&tlb, vma, addr, end, PAGE_NONE, @@ -765,6 +768,7 @@ static int vma_replace_policy(struct vm_area_struct *vm= a, if (IS_ERR(new)) return PTR_ERR(new); =20 + vma_mark_locked(vma); if (vma->vm_ops && vma->vm_ops->set_policy) { err =3D vma->vm_ops->set_policy(vma, new); if (err) --=20 2.37.2.789.g6183377224-goog