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=-7.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable 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 BBA9CC04EB9 for ; Wed, 5 Dec 2018 13:24:41 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 8C9532082B for ; Wed, 5 Dec 2018 13:24:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="bytJH3ZP" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8C9532082B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=7IONxwywJfEG+b2j0tLX2jyAfj4dlUQUoWNOpCcAiYk=; b=bytJH3ZPh8O5oy 5lPrficANfZZhoU7/CrbYcuquCSZEYcQXxGvIaAyCH2Hsw53aWkTrmpmwkvfi7dQMKEUgL2bjx4TB e5aFygpb9h3qGLTtq6dXTXyKE7OAoNvuAotAtdJTk6i2mw+hYPERDD/81cdAccZ7c3egTxaiwjl+V ceGIYFMzgZnaoUmounnzj62VoB1Yjjuuy8zJXhhyMs9DZA6vK0qZz+QLsQRI0UkR0IJffqEHAtwQh LKDUfygZWOY+r8nwZ0Sre50e8VCMULnJz7DU4jIrfw8CH3M/aNnfR3qcQoqFGvaNgI6XgjHLgYX5x CaravYprp9DQp8NilnCg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gUXAO-00054Z-2K; Wed, 05 Dec 2018 13:24:40 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gUXAK-00053H-Of for linux-arm-kernel@lists.infradead.org; Wed, 05 Dec 2018 13:24:38 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 4EB0BA78; Wed, 5 Dec 2018 05:24:24 -0800 (PST) Received: from edgewater-inn.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 1D8C43F59C; Wed, 5 Dec 2018 05:24:24 -0800 (PST) Received: by edgewater-inn.cambridge.arm.com (Postfix, from userid 1000) id CCB5A1AE0BC3; Wed, 5 Dec 2018 13:24:44 +0000 (GMT) Date: Wed, 5 Dec 2018 13:24:44 +0000 From: Will Deacon To: Daniel Borkmann Subject: Re: [PATCH v4 2/2] arm64/bpf: don't allocate BPF JIT programs in module memory Message-ID: <20181205132444.GA15631@arm.com> References: <20181123221804.440-1-ard.biesheuvel@linaro.org> <20181123221804.440-3-ard.biesheuvel@linaro.org> <20181130182629.GA16085@arm.com> <20181203124930.GB25097@arm.com> <12954298-de06-349e-6df2-c218e5bf09a3@iogearbox.net> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <12954298-de06-349e-6df2-c218e5bf09a3@iogearbox.net> User-Agent: Mutt/1.5.23 (2014-03-12) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181205_052436_812129_F5794D36 X-CRM114-Status: GOOD ( 23.82 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Kees Cook , Eric Dumazet , Jann Horn , Catalin Marinas , Ard Biesheuvel , Alexei Starovoitov , Linux Kernel Mailing List , "" , Arnd Bergmann , Jessica Yu , Rick Edgecombe , "David S. Miller" , linux-arm-kernel Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Dec 05, 2018 at 01:24:17PM +0100, Daniel Borkmann wrote: > On 12/04/2018 04:45 PM, Ard Biesheuvel wrote: > > On Mon, 3 Dec 2018 at 13:49, Will Deacon wrote: > >> On Fri, Nov 30, 2018 at 08:20:06PM +0100, Ard Biesheuvel wrote: > >>> On Fri, 30 Nov 2018 at 19:26, Will Deacon wrote: > >>>> On Fri, Nov 23, 2018 at 11:18:04PM +0100, Ard Biesheuvel wrote: > >>>>> diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c > >>>>> index a6fdaea07c63..76c2ab40c02d 100644 > >>>>> --- a/arch/arm64/net/bpf_jit_comp.c > >>>>> +++ b/arch/arm64/net/bpf_jit_comp.c > >>>>> @@ -940,3 +940,16 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) > >>>>> tmp : orig_prog); > >>>>> return prog; > >>>>> } > >>>>> + > >>>>> +void *bpf_jit_alloc_exec(unsigned long size) > >>>>> +{ > >>>>> + return __vmalloc_node_range(size, PAGE_SIZE, BPF_JIT_REGION_START, > >>>>> + BPF_JIT_REGION_END, GFP_KERNEL, > >>>>> + PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE, > >>>>> + __builtin_return_address(0)); > >>>> > >>>> I guess we'll want VM_IMMEDIATE_UNMAP here if Rich gets that merged. > >>> > >>> I think akpm already queued up that patch. > >>> > >>>> In the > >>>> meantime, I wonder if it's worth zeroing the region in bpf_jit_free_exec()? > >>>> (although we'd need the size information...). > >>>> > >>> > >>> Not sure. What exactly would that achieve? > >> > >> I think the zero encoding is guaranteed to be undefined, so it would limit > >> the usefulness of any stale, executable TLB entries. However, we'd also need > >> cache maintenance to make that stuff visible to the I side, so it's probably > >> not worth it, especially if akpm has queued the stuff from Rich. > >> > >> Maybe just add an: > >> > >> /* FIXME: Remove this when VM_IMMEDIATE_UNMAP is supported */ > >> #ifndef VM_IMMEDIATE_UNMAP > >> #define VM_IMMEDIATE_UNMAP 0 > >> #endif > >> > >> so we remember to come back and sort this out? Up to you. > > > > I'll just make a note to send out that patch once the definition lands via -akpm > > Could I get an ACK from you for this patch, then I'd take the series into bpf-next. Gah, thanks for the ping: I thought I acked this initially, but turns out I didn't. Acked-by: Will Deacon Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel