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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 56254C33C99 for ; Tue, 7 Jan 2020 09:03:15 +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 2812720715 for ; Tue, 7 Jan 2020 09:03:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Xd65ktVq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2812720715 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ubuntu.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=gpIXP5qfRnNgK+2d8BnEolMAL25Kj+ci8MgetNvgFwI=; b=Xd65ktVqzy12mu xStYC02CQ5vKenkRliUXzvnsRftTonHm9j3tN5TnXoja5cNZeKVysxE5CTIen06Xf5bjgG/+2ZAj3 YHdssX1j23xNS3NLSS4Ulr5NRwssCRhUK0+AhjAUMNNeDWD3V0gaEsPKPMN8Uvrj67CDpDdsYZcb5 Pbn68kYr+42uURL5QXMiiLiW1uCWOnUkMZR58v8B4o22BtE+D8T98e4MZeLnaTWE5745eK53QBAjp MZwFSrautuhZ41Eq4E9eWQgVDYJoRybPb4Qm2ijIH8rFQ5qB4qddEPjIrLeVKEtZrBNqS7pirZC4q rSsNytoJbSEoXZkMJybA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1ioklW-00066b-Ny; Tue, 07 Jan 2020 09:03:06 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1ioklS-00065V-Gn for linux-arm-kernel@lists.infradead.org; Tue, 07 Jan 2020 09:03:04 +0000 Received: from ip-109-41-1-227.web.vodafone.de ([109.41.1.227] helo=wittgenstein) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1ioklG-0004Nl-2G; Tue, 07 Jan 2020 09:02:50 +0000 Date: Tue, 7 Jan 2020 10:02:27 +0100 From: Christian Brauner To: Amanieu d'Antras Subject: Re: [PATCH 2/7] arm64: Implement copy_thread_tls Message-ID: <20200107090219.jl4py4u2zvofwnbh@wittgenstein> References: <20200102172413.654385-1-amanieu@gmail.com> <20200102172413.654385-3-amanieu@gmail.com> <20200102180130.hmpipoiiu3zsl2d6@wittgenstein> <20200106173953.GB9676@willie-the-truck> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20180716 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200107_010302_693518_FC2D33F4 X-CRM114-Status: GOOD ( 12.63 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: keescook@chromium.org, Will Deacon , linux-kernel@vger.kernel.org, "# 3.4.x" , Christian Brauner , linux-kselftest@vger.kernel.org, Will Deacon , Linux ARM 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 [Cc Kees in case he knows something about where arch specific tests live or whether we have a framework for this] On Mon, Jan 06, 2020 at 07:03:32PM +0100, Amanieu d'Antras wrote: > On Mon, Jan 6, 2020 at 6:39 PM Will Deacon wrote: > > I also ran the native and compat selftests but, unfortunately, they all > > pass even without this patch. Do you reckon it would be possible to update > > them to check the tls pointer? > > Here's the program I used for testing on arm64. I considered adding it > to the selftests but there is no portable way of reading the TLS > register on all architectures. I'm not saying you need to do this right now. It feels like we must've run into the "this is architecture specific"-and-we-want-to-test-this issue before... Do we have a place where architecture specific selftests live? > > #include > #include > #include > #include > > #define __NR_clone3 435 > struct clone_args { > uint64_t flags; > uint64_t pidfd; > uint64_t child_tid; > uint64_t parent_tid; > uint64_t exit_signal; > uint64_t stack; > uint64_t stack_size; > uint64_t tls; > }; > > #define USE_CLONE3 > > int main() { > printf("Before fork: tp = %p\n", __builtin_thread_pointer()); > #ifdef USE_CLONE3 > struct clone_args args = { > .flags = CLONE_SETTLS, > .tls = (uint64_t)__builtin_thread_pointer(), > }; > int ret = syscall(__NR_clone3, &args, sizeof(args)); > #else > int ret = syscall(__NR_clone, CLONE_SETTLS, 0, 0, > __builtin_thread_pointer(), 0); > #endif > printf("Fork returned %d, tp = %p\n", ret, __builtin_thread_pointer()); > } _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel