From mboxrd@z Thu Jan 1 00:00:00 1970 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 87C60C4332F for ; Sat, 17 Dec 2022 11:44:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229985AbiLQLoe (ORCPT ); Sat, 17 Dec 2022 06:44:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44768 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230105AbiLQLo0 (ORCPT ); Sat, 17 Dec 2022 06:44:26 -0500 Received: from mail-wm1-x334.google.com (mail-wm1-x334.google.com [IPv6:2a00:1450:4864:20::334]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 65A6013EAD for ; Sat, 17 Dec 2022 03:44:25 -0800 (PST) Received: by mail-wm1-x334.google.com with SMTP id bg10so3475526wmb.1 for ; Sat, 17 Dec 2022 03:44:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=GBSVB2Oi5TbTIwwaOpRKfNJzplXssZ9oR2ZKAZimo4E=; b=k0fpKgaZIUGDT6X0DZ06jlzs25bISKhHU8bB9iJXybs6SUxcmHz9r0S8xiebXfjzX8 THW+vbhhcdK+2AP0ygoxLy2aURFM1ZisP7eBv1m0Y1yBXewI5nBtOl+ZZ3jOn+lBcoTr T4jbe7AmYMuKIgpOr2CCC7SsOZMuIbfKb52WMBhhAxowekO3hr9891cassApDuvzcSYV NfOWeLj2rP1/jdtA1r6KV9xpZmrQW3OBh4AT1J8oMES7ixoKtzYbANxIlTaYyYyQM3Mm npGVkj3MjY/3JPn/uDpJJNcLMuoSN+UR1B3jVLSvmYo2UqF30KFUzfh7M5c+5EVTv6Zc 1d4Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=GBSVB2Oi5TbTIwwaOpRKfNJzplXssZ9oR2ZKAZimo4E=; b=mbe3h3CmkBpL3aIgAz6EI0T7Gi/wr7otr+dNpwivDoasrUGWBLLGPLSrwzbnt2T7C4 k6PSHSgsN699Vu8jcrW/31NgQGKwaDZxebyd1I/PAJxVkWG7ZCQ6x5d+jk/C566IuaYE atz/dmovx+Hi29UdI6Se/rnEFg/KM7jRZ1w/SKcNQTuNWbc5rYrba3x+TaUm516f6/WD OI8ALT5cDOaenJtOkqH+5cd4QYk3AOJ8BA7YHVFQWr5p+YNnz7HJoiCr7cTJH5plPNMZ 4sOM1zDaelsuUPnAXriO4ZJk2IbBFlisO2PC6ZUDLf4jfgwsotjiXnOcfEa/g4nRvEys Pr+w== X-Gm-Message-State: AFqh2krLI2SzyrdOO8naALlEu9cb6SYSjWwS2jb3vJtdq5wjQ/Tohq3J wcFEi2iJ5jUNrTZFatZ5b/M= X-Google-Smtp-Source: AMrXdXt6sqQP1NtKTr05MgB5iN/MzMucgIdOEJXOXRqsztLP+6QiRv2Fa9AnrwbtJV0dBnZ1y4jSWg== X-Received: by 2002:a05:600c:210f:b0:3d3:4406:8a3c with SMTP id u15-20020a05600c210f00b003d344068a3cmr4380165wml.32.1671277463842; Sat, 17 Dec 2022 03:44:23 -0800 (PST) Received: from localhost ([2a00:23c5:dc8c:8701:1663:9a35:5a7b:1d76]) by smtp.gmail.com with ESMTPSA id 8-20020a05600c020800b003b4935f04a4sm6505486wmi.5.2022.12.17.03.44.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 17 Dec 2022 03:44:23 -0800 (PST) Date: Sat, 17 Dec 2022 11:44:22 +0000 From: Lorenzo Stoakes To: Baoquan He Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, urezki@gmail.com, stephen.s.brennan@oracle.com, willy@infradead.org, akpm@linux-foundation.org, hch@infradead.org Subject: Re: [PATCH v2 2/7] mm/vmalloc.c: add flags to mark vm_map_ram area Message-ID: References: <20221217015435.73889-1-bhe@redhat.com> <20221217015435.73889-3-bhe@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221217015435.73889-3-bhe@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Dec 17, 2022 at 09:54:30AM +0800, Baoquan He wrote: > @@ -2229,8 +2236,12 @@ void vm_unmap_ram(const void *mem, unsigned int count) > return; > } > > - va = find_vmap_area(addr); > + spin_lock(&vmap_area_lock); > + va = __find_vmap_area((unsigned long)addr, &vmap_area_root); > BUG_ON(!va); > + if (va) > + va->flags &= ~VMAP_RAM; > + spin_unlock(&vmap_area_lock); > debug_check_no_locks_freed((void *)va->va_start, > (va->va_end - va->va_start)); > free_unmap_vmap_area(va); Would it be better to perform the BUG_ON() after the lock is released? You already check if va exists before unmasking so it's safe. Also, do we want to clear VMAP_BLOCK here?