From patchwork Mon Aug 29 21:25:19 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suren Baghdasaryan X-Patchwork-Id: 12958485 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 975BEECAAD2 for ; Mon, 29 Aug 2022 21:45:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:From:Subject:Message-ID: References:Mime-Version:In-Reply-To:Date:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=4KotQx0+/6p1aeN0sXJ54jMLkR45817Xx3OhPwKjxRQ=; b=FV/kcufsShr/Pnr7BFmpK0ujHG 1c20i5y1uJrUtlr3+7mEPfMjOA37eDgkTor9z8h09bfWqHUx0R9kOHNqciZqtloV4LlWzN2tiFqMO fMVX4FjmpVooxuXLg+02Kiw/Ye6D1+rWWTG7PTgM9TRKqanop2pYL36DtSqmN7T4WeIEczJMIBlNS tNl16CyKdo6PD1diCkmoirKtKb9O/m5AgG2ooZ2SV3G6FOTmVj0XZUm9W+Q1GTE/RtJ1kNmcpvIT7 ei1JbqtTJYayXrbsJAJvBu9gWX/yfeWMT/YBiNFyFBrXxrhIC+qCVU/Zyec09tn/rYJYoW1ZwdIq0 DGlZYPfA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oSmYQ-00CtdY-44; Mon, 29 Aug 2022 21:44:22 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oSmXo-00CtVm-99 for linux-arm-kernel@bombadil.infradead.org; Mon, 29 Aug 2022 21:43:44 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Type:Cc:To:From:Subject: Message-ID:References:Mime-Version:In-Reply-To:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=NYe8oOJNfY11QXfRhGHbzq3PtP5qYF5OBWlNRgI/ICw=; b=Oh/vxzBHEf+tanbTnfwve01QGL YRjqXwaHRvhEvEcDwNyoxPWkWzMngm4ZzINBsXVjZzLY93rnuEr+JTo+u1ZAn7PFggfgD/6hlwUJU 1UE5IVVcNXEtLwRQ6fEN6H8Psj4NfRpoQzQ7JEBBAokn+DA+VAAwyJPmzm4yT49UKx5QBf/emvKQJ gVYnDum9FETBb6GX4c+2DUbKlnbk7q9BrKPQ7HdBjyI40I8w2UR64+IY382XqB4VleNdSSGbDpfzy u34zhv8CArG+nrBzPOXTwWEWha2ze0l85uaMGr9AQ+xJPuo+midxAzDqCGvduOF87cnfto12uatkC vYW3PhXg==; Received: from mail-yw1-x1149.google.com ([2607:f8b0:4864:20::1149]) by casper.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oSmGn-003PwO-Bl for linux-arm-kernel@lists.infradead.org; Mon, 29 Aug 2022 21:26:11 +0000 Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-33dc888dc62so147197017b3.4 for ; Mon, 29 Aug 2022 14:26:07 -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; bh=NYe8oOJNfY11QXfRhGHbzq3PtP5qYF5OBWlNRgI/ICw=; b=gO3BAu2tPnt5ajc2wonv12EyC/cky1iEagPrWs8TIsmrfOPEdnZICXVlt39nBHt3WW tTV55lawhiZGMRBmA7gdT3YGawg8JjnJFEe5+7PrxS+L7PuBHZcRqu/eGZS5+7HkD+/v WBe3l/+DgKFH8adTgdOoThkCyU3oUkPdhTm9bGePyXaQUn5Kf04YxKMvEOmZ7WCBWmLN BXoUJ7D1rnsd47mFF47xSWH/cS8u1UFuDHVuHAEZYgUQ7/tjgR1JcWJgnN0k47FfJT+A /f4moE4fkIQHN9Nb1qOXqxym1C/DCmqaA6CVw+YBif80n7h7hRdtT5oL02KCkdJe7ned iBKA== 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; bh=NYe8oOJNfY11QXfRhGHbzq3PtP5qYF5OBWlNRgI/ICw=; b=5BIJcI39kHK9UhYU8Cg+O5BjzPnuU+1VRcfh6rzG+HO6fm/1fGUQq9O/NmSpMB1zM4 +xAPxRS5O5huJEkRgfz740yBk3K+EahNSNktIdv/ZH21cgYz5pnAfhRRaGRUp8OnXCsg jIOoWkiUmNtqwJ8fm6ztqMm45JHjExBCimJTTJYFOGI+UIvHKgkNV8xv8nRmWDG1ytzH b6dHzo7Kl4vfK/c4SL+8lZ3YR7V+/RJvAidJcR+Ce6SceEvnycUSBYDxqPwqEBgNhrWE FDBwovU5hp/b1Ru9dd3O/xr3PZ4qUqGQncd+ohi27lBSsRbLTox6jyUDzkXCJ998kSIs UsCA== X-Gm-Message-State: ACgBeo0VaTnfiGlKIJ0i/UdTzn8nnNQGco/3Z+8PfJZnVMxJp3vOQO8R xy7Zb5HKElxPK+Bt7arMKSMnOjaMq4c= X-Google-Smtp-Source: AA6agR7nmkBRROpS79vTx3reOak4mrTZffxlmMbexsEub45N/wO5CnqJNjif+IJpyxwlCbKERnK2QUttv8k= X-Received: from surenb-spec.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3e30]) (user=surenb job=sendgmr) by 2002:a25:d944:0:b0:695:6056:7dda with SMTP id q65-20020a25d944000000b0069560567ddamr9840482ybg.277.1661808364958; Mon, 29 Aug 2022 14:26:04 -0700 (PDT) Date: Mon, 29 Aug 2022 21:25:19 +0000 In-Reply-To: <20220829212531.3184856-1-surenb@google.com> Mime-Version: 1.0 References: <20220829212531.3184856-1-surenb@google.com> X-Mailer: git-send-email 2.37.2.672.g94769d06f0-goog Message-ID: <20220829212531.3184856-17-surenb@google.com> Subject: [RFC PATCH 16/28] kernel/fork: assert no VMA readers during its destruction 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@techsingularity.net, 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, riel@surriel.com, 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220829_222609_481698_EB02C319 X-CRM114-Status: GOOD ( 10.77 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Assert there are no holders of VMA lock for reading when it is about to be destroyed. Signed-off-by: Suren Baghdasaryan --- include/linux/mm.h | 8 ++++++++ kernel/fork.c | 2 ++ 2 files changed, 10 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index dc72be923e5b..0d9c1563c354 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -676,6 +676,13 @@ static inline void vma_assert_write_locked(struct vm_area_struct *vma, int pos) VM_BUG_ON_VMA(vma->vm_lock_seq != READ_ONCE(vma->vm_mm->mm_lock_seq), vma); } +static inline void vma_assert_no_reader(struct vm_area_struct *vma) +{ + VM_BUG_ON_VMA(rwsem_is_locked(&vma->lock) && + vma->vm_lock_seq != READ_ONCE(vma->vm_mm->mm_lock_seq), + vma); +} + #else /* CONFIG_PER_VMA_LOCK */ static inline void vma_init_lock(struct vm_area_struct *vma) {} @@ -685,6 +692,7 @@ static inline bool vma_read_trylock(struct vm_area_struct *vma) static inline void vma_read_unlock(struct vm_area_struct *vma) {} static inline void vma_assert_locked(struct vm_area_struct *vma) {} static inline void vma_assert_write_locked(struct vm_area_struct *vma, int pos) {} +static inline void vma_assert_no_reader(struct vm_area_struct *vma) {} #endif /* CONFIG_PER_VMA_LOCK */ diff --git a/kernel/fork.c b/kernel/fork.c index 1872ad549fed..b443ba3a247a 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -487,6 +487,8 @@ static void __vm_area_free(struct rcu_head *head) { struct vm_area_struct *vma = container_of(head, struct vm_area_struct, vm_rcu); + /* The vma should either have no lock holders or be write-locked. */ + vma_assert_no_reader(vma); kmem_cache_free(vm_area_cachep, vma); } #endif