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 X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4D2FAC2BA19 for ; Tue, 14 Apr 2020 13:02:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1D3572075E for ; Tue, 14 Apr 2020 13:02:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="bOGD0uXf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2502506AbgDNNCv (ORCPT ); Tue, 14 Apr 2020 09:02:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S2502475AbgDNNCL (ORCPT ); Tue, 14 Apr 2020 09:02:11 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9952DC061A0C; Tue, 14 Apr 2020 06:02:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=T6z0bd+fqDvkVl7fHhA0/8UcwUryWcByqLrcGyIrH5s=; b=bOGD0uXfBJxjATisnWE13caPpw yM9EhSXpjZ/69j68Wx2mvv4rPOnCCnL4tZZOnQ/NrScoRBkaop1XY/iOcVOh0AkRZpQOQz5AVjtpv cMV61Q/X5bapJJYHYlrURSsjHy7o3Gg83EN4vlKiDfRTyRH5zdQnD3aKzJJQD/Kfm9D/MZmyrS5dF 6Bl0eEJCl5IRt9WB6xgPE10wzHrxN2D4jZ8Wklbvo3XU7xQtw94VjIEPtaSS9ZKYl/NsjwULmC+Yi /zy17VuWZ3bNc0Ndims46fX3T7ww6xbwzSO+4eEXTFMbss0b2VRfn9nH14CqQ8MjZl0Uf7RSHY+CP kRablIbA==; Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jOLCV-0005fb-Ei; Tue, 14 Apr 2020 13:02:03 +0000 Date: Tue, 14 Apr 2020 06:02:03 -0700 From: Christoph Hellwig To: Nicholas Piggin Cc: Christoph Hellwig , Borislav Petkov , Catalin Marinas , "H. Peter Anvin" , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, Ingo Molnar , Thomas Gleixner , Will Deacon , x86@kernel.org Subject: Re: [PATCH v2 4/4] mm/vmalloc: Hugepage vmalloc mappings Message-ID: <20200414130203.GA20867@infradead.org> References: <20200413125303.423864-1-npiggin@gmail.com> <20200413125303.423864-5-npiggin@gmail.com> <20200414072316.GA5503@infradead.org> <1586864403.0qfilei2ft.astroid@bobo.none> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1586864403.0qfilei2ft.astroid@bobo.none> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 14, 2020 at 10:13:44PM +1000, Nicholas Piggin wrote: > Which case? Usually the answer would be because you don't want to use > contiguous physical memory and/or you don't want to use the linear > mapping. But with huge pages you do by definition already use large contiguous areas. So you want allocations larger than "small" huge pages but not using gigantic pages using vmalloc?