From nobody Thu Sep 18 18:47:27 2025 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 025F6C352A1 for ; Sun, 4 Dec 2022 01:32:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229762AbiLDBc3 (ORCPT ); Sat, 3 Dec 2022 20:32:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35648 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229597AbiLDBcT (ORCPT ); Sat, 3 Dec 2022 20:32:19 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E795D1A076 for ; Sat, 3 Dec 2022 17:31:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1670117484; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=p5OPg+DQ4r4Z/JFMiJuaclM/YLWn2Go/JtLJ0xxYwus=; b=enByNln7ytaE3T+QThfvPczLgEt7+4H6qCqvmfRfZbPzi4FoDhQwqXzUSyDsMWUG+ZLfji jidxf4fbMbDKng15ry2+H+8L5LmtMfrwLjiuXFFuvNBrnfY6Gqf6i5Gq2hbZ0QYnPuh42y yvjA4Abx6jXM9xUR8tkrj9b5Jnk0tJ4= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-306-uIXwTZ5OO42nv2qg208mSw-1; Sat, 03 Dec 2022 20:31:20 -0500 X-MC-Unique: uIXwTZ5OO42nv2qg208mSw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 446C429ABA17; Sun, 4 Dec 2022 01:31:20 +0000 (UTC) Received: from MiWiFi-R3L-srv.redhat.com (ovpn-12-31.pek2.redhat.com [10.72.12.31]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2E3D4141511E; Sun, 4 Dec 2022 01:31:15 +0000 (UTC) From: Baoquan He To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, stephen.s.brennan@oracle.com, urezki@gmail.com, willy@infradead.org, akpm@linux-foundation.org, hch@infradead.org, Baoquan He Subject: [PATCH v1 4/7] mm/vmalloc: explicitly identify vm_map_ram area when shown in /proc/vmcoreinfo Date: Sun, 4 Dec 2022 09:30:43 +0800 Message-Id: <20221204013046.154960-5-bhe@redhat.com> In-Reply-To: <20221204013046.154960-1-bhe@redhat.com> References: <20221204013046.154960-1-bhe@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Now, by marking VMAP_RAM in vmap_area->flags for vm_map_ram area, we can clearly differentiate it with other vmalloc areas. So in s_show(), change the ambiguous checking 'if (!va->vm) to clear "if (!va->vm && (va->flags & VMAP_RAM))". This let's picks out vm_map_ram area, and avoids the being unmapped normal vmalloc area to be mistakenly recognized as vm_map_ram area. Meanwhile, the code comment above vm_map_ram area checking in s_show() is not needed any more, remove it here. Signed-off-by: Baoquan He --- mm/vmalloc.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index e6b46da3e044..3c60026fb162 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -4181,11 +4181,7 @@ static int s_show(struct seq_file *m, void *p) =20 va =3D list_entry(p, struct vmap_area, list); =20 - /* - * s_show can encounter race with remove_vm_area, !vm on behalf - * of vmap area is being tear down or vm_map_ram allocation. - */ - if (!va->vm) { + if (!va->vm && (va->flags & VMAP_RAM)) { seq_printf(m, "0x%pK-0x%pK %7ld vm_map_ram\n", (void *)va->va_start, (void *)va->va_end, va->va_end - va->va_start); --=20 2.34.1