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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 05304C3DA7F for ; Thu, 15 Aug 2024 16:33:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=F4amGO8mOa+QkkiuatPGel8U1wodPg720SxUM3LB7Os=; b=nogoe6m4HArk5N/mtGPT/dJlpx fAdCmdrFxleBpVDp+utLCYFPSzLaHX9fp6mTnH5BxvoXGHZ9m3SZapJc5iPzWgDcjE6Ci24N1MH7m /NwT+8gxDUm862nmpeW3dYc7DbaMnAWZbJ0UtncgESXcfarC6HpXLJ9/yq4H2xi2beXdsXb1d1arB UN0aRZ4BewsUidUv95OYlC3CFBPfictQXbu2fXy+9+BX0gcDjzQ5kTSJ8VU3TXKMPj5NwreYb4JpK Cm5WOlluBbGS7cPtA3yqmh0y0V56IL8NO4tdZsqhjI19bUn7xa6C0YMHARtmhOd2FK/lu7FO7A9uD gpvhaI7A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sedP5-0000000AWg9-0OPy; Thu, 15 Aug 2024 16:32:47 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sedOL-0000000AWYO-3H8i; Thu, 15 Aug 2024 16:32:07 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 47EB014BF; Thu, 15 Aug 2024 09:32:24 -0700 (PDT) Received: from e133380.arm.com (e133380.arm.com [10.1.197.55]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 94A073F6A8; Thu, 15 Aug 2024 09:31:52 -0700 (PDT) Date: Thu, 15 Aug 2024 17:31:49 +0100 From: Dave Martin To: Mark Brown Cc: Catalin Marinas , Will Deacon , Jonathan Corbet , Andrew Morton , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Arnd Bergmann , Oleg Nesterov , Eric Biederman , Shuah Khan , "Rick P. Edgecombe" , Deepak Gupta , Ard Biesheuvel , Szabolcs Nagy , Kees Cook , "H.J. Lu" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Florian Weimer , Christian Brauner , Thiago Jung Bauermann , Ross Burton , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH v10 23/40] arm64/signal: Set up and restore the GCS context for signal handlers Message-ID: References: <20240801-arm64-gcs-v10-0-699e2bd2190b@kernel.org> <20240801-arm64-gcs-v10-23-699e2bd2190b@kernel.org> <08932f6d-01ef-40e8-97d2-08f0d2016191@sirena.org.uk> <7fa96f26-5bf6-490f-8986-258033fbfe0e@sirena.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7fa96f26-5bf6-490f-8986-258033fbfe0e@sirena.org.uk> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240815_093201_893272_6796256E X-CRM114-Status: GOOD ( 21.11 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Aug 15, 2024 at 04:29:54PM +0100, Mark Brown wrote: > On Thu, Aug 15, 2024 at 04:11:56PM +0100, Dave Martin wrote: > > On Thu, Aug 15, 2024 at 03:45:45PM +0100, Mark Brown wrote: > > > On Thu, Aug 15, 2024 at 02:37:22PM +0100, Dave Martin wrote: > > > > > Is there a test for taking and returning from a signal on an alternate > > > > (main) stack, when a shadow stack is in use? Sounds like something > > > > that would be good to check if not. > > > > Not specifically for any of the architectures. > > > Can you see any reason why this shouldn't work? > > No, it's expected to work - I'm just not specifically aware of an > explicit test for it. Possibly some of the userspace bringup work > might've covered it? Any libc tests for altstack support should've > exercised it for example. That's true; if libc is built to use shadow stack, generic API tests ought to cover this. > > Maybe I'll hacking up a test if I get around to it, but don't take this > > as a promise! > > Thanks for your firm commitment! :P No problem... Cheers ---Dave