From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Wed, 24 Feb 2021 09:50:57 +0100 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by lore.white.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1lEpsn-0004gU-4V for lore@lore.pengutronix.de; Wed, 24 Feb 2021 09:50:57 +0100 Received: from merlin.infradead.org ([2001:8b0:10b:1231::1]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lEpsm-0007rJ-8I for lore@pengutronix.de; Wed, 24 Feb 2021 09:50:56 +0100 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:From:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=KIa06qPbVzopomSJUyBpkHoab0+vIa7aiSA+rrzUukI=; b=tf+ICequoZPHr7mPa0vqgBe9T VpLxu/rdE453avMx+VwkQrpxUR02ZZDJUp/d0OxNWw8UATnJ9SpLnQR+RFm/SJ33uKoTkuMZ2HNaw qrNGnzB4k56WUMr/Gj5Gs0sLSzdkHQwta/lf5pxuD4OJTdSpsa/edEnKoWLBa8TgfiMTME0VNC2fo mvMpYDDcYM/BXZ2PYaPczUHuYH0jgaEcgC4l9f1+yGC1+bWc5ZJQVJr0GualrM7gwTIiiZy0P2+ko 06ZbDFYfv2+jfmJN11RwiMFZdtl08FmqP/CXjcw89qdREO3D70PbPK7pAAnndCNS/aV0cIJxxUl4q qDvwMfj1A==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lEprk-0006WE-Rq; Wed, 24 Feb 2021 08:49:52 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1lEprg-0006V2-45 for barebox@lists.infradead.org; Wed, 24 Feb 2021 08:49:49 +0000 Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lEprf-0007Vt-7S; Wed, 24 Feb 2021 09:49:47 +0100 Received: from sha by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1lEprd-00069F-IJ; Wed, 24 Feb 2021 09:49:45 +0100 Date: Wed, 24 Feb 2021 09:49:45 +0100 To: Ahmad Fatoum Message-ID: <20210224084945.GI5549@pengutronix.de> References: <20210223072427.166689-1-ahmad@a3f.at> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210223072427.166689-1-ahmad@a3f.at> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-IRC: #ptxdist @freenode X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-Uptime: 09:49:37 up 6 days, 12:13, 61 users, load average: 0.01, 0.17, 0.21 User-Agent: Mutt/1.10.1 (2018-07-13) From: Sascha Hauer X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210224_034948_219540_4A0007B4 X-CRM114-Status: GOOD ( 23.48 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: barebox@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" X-SA-Exim-Connect-IP: 2001:8b0:10b:1231::1 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.ext.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-2.9 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH 1/2] kbuild: add '-fno-stack-check' to barebox build options X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.ext.pengutronix.de) On Tue, Feb 23, 2021 at 08:24:26AM +0100, Ahmad Fatoum wrote: > This ports over Linux commit 3ce120b16cc5 ("kbuild: add > '-fno-stack-check' to kernel build options"): > > Author: Linus Torvalds > > kbuild: add '-fno-stack-check' to kernel build options > > It appears that hardened gentoo enables "-fstack-check" by default for > gcc. > > That doesn't work _at_all_ for the kernel, because the kernel stack > doesn't act like a user stack at all: it's much smaller, and it doesn't > auto-expand on use. So the extra "probe one page below the stack" code > generated by -fstack-check just breaks the kernel in horrible ways, > causing infinite double faults etc. > > [ I have to say, that the particular code gcc generates looks very > stupid even for user space where it works, but that's a separate > issue. ] > > Signed-off-by: Linus Torvalds > > I am porting it, because it may become more acute with the incoming > support for multiple stacks (via initjmp). > > Signed-off-by: Ahmad Fatoum > --- Applied, thanks Sascha > Makefile | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/Makefile b/Makefile > index f3c85cff9430..fa7fbbeb35f0 100644 > --- a/Makefile > +++ b/Makefile > @@ -622,6 +622,9 @@ KBUILD_CFLAGS += $(call cc-option, -fno-delete-null-pointer-checks,) > # disable invalid "can't wrap" optimizations for signed / pointers > KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow) > > +# Make sure -fstack-check isn't enabled (like gentoo apparently did) > +KBUILD_CFLAGS += $(call cc-option,-fno-stack-check) > + > KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member) > > # Align the bit size of userspace programs with the kernel > -- > 2.30.0 > > > _______________________________________________ > barebox mailing list > barebox@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/barebox > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox