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=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 C4BD2C2BA83 for ; Fri, 7 Feb 2020 17:38:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 96FD020838 for ; Fri, 7 Feb 2020 17:38:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="DIPvIFNW" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727589AbgBGRim (ORCPT ); Fri, 7 Feb 2020 12:38:42 -0500 Received: from mail-pj1-f67.google.com ([209.85.216.67]:40440 "EHLO mail-pj1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726897AbgBGRim (ORCPT ); Fri, 7 Feb 2020 12:38:42 -0500 Received: by mail-pj1-f67.google.com with SMTP id 12so1176701pjb.5 for ; Fri, 07 Feb 2020 09:38:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=OiMCk3HNlA+VYlmzK8C7KfB3ijS3pxsMTQRh/DwJS98=; b=DIPvIFNWz82jW5jdNCN7WS3F+SQ26RG5xOeXI72hbKx5hdyOiREZSJbZJRFbzMxP5z GcPlR/hwSDEjldjA28tMgKQ+vWpcgcf8pVsbeIQ+lgQCNhQy1Sgh8lMRAlYe6EcURoCb ONgSclgsXPB3wV2jCGTyUfNmcfqD3NohxJmKTRdEtZMUrkvI5CZwetjarcHTaMN0pMpk Z9r98dl5GyAkmFMCPcSz9LXz5BziHAoGsg0BVyc5hubYQdGwgic0CCLiLEdS1T56j9LL p2YHC+NTZWs/HWexwfDLFRad9gpJSqs/egEMNOU6MiEMULrKumUZknJBBNr3ZfSJMeLS s3rQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=OiMCk3HNlA+VYlmzK8C7KfB3ijS3pxsMTQRh/DwJS98=; b=PQO+M1sP6kt+s4aJVR069dbAnTJ3iIKfqkUDtxSbQjYg2ouSknBle8XG6rFlfuzoCU JUFHdJ/rSMsUx5S6Ty2+FU4Vf0xlo4e7QsxYzDR9cUHrzqQD53Ekv/m5PLn5Y/oCZv2o pyExjbdng0q/ETd/ZpTCMCfZGIsYory6Y+Wh0IUlE92PEW64QMK9aII4r+5m1rRIF6Pm fSEpj2zyM+5D623sCk/6jUCOc4YJmm2k8pFdKZlLvafU4aINLIbmMpk+VcBLuwJ1TJr7 1o2xnuYbE4a7sSFlrO4o9+mIEOO2u1Iy4QftiWKEmOn4ztW74dsMdxRP22VCdXd9dngO 64Rg== X-Gm-Message-State: APjAAAXLWCK0plvcN3KdUilS977TE36K0XtK8OrNurS60vK8s5RkZ6zq jVBs+xP7Zz4NBiho48zgjrY= X-Google-Smtp-Source: APXvYqwp1PutHtvP0hC+zOIRQmLP5aOwlkctuCUXhYERECa9pdF/NW68x0lKYXiMUZqTtWJAUoo97w== X-Received: by 2002:a17:90a:26e1:: with SMTP id m88mr5108116pje.101.1581097120913; Fri, 07 Feb 2020 09:38:40 -0800 (PST) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id c19sm3803503pgh.8.2020.02.07.09.38.39 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 07 Feb 2020 09:38:40 -0800 (PST) Date: Fri, 7 Feb 2020 09:38:39 -0800 From: Guenter Roeck To: Christophe Leroy Cc: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH] powerpc: Fix CONFIG_TRACE_IRQFLAGS with CONFIG_VMAP_STACK Message-ID: <20200207173839.GA8313@roeck-us.net> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 07, 2020 at 05:20:57PM +0000, Christophe Leroy wrote: > When CONFIG_PROVE_LOCKING is selected together with (now default) > CONFIG_VMAP_STACK, kernel enter deadlock during boot. > > At the point of checking whether interrupts are enabled or not, the > value of MSR saved on stack is read using the physical address of the > stack. But at this point, when using VMAP stack the DATA MMU > translation has already been re-enabled, leading to deadlock. > > Don't use the physical address of the stack when > CONFIG_VMAP_STACK is set. > > Signed-off-by: Christophe Leroy > Reported-by: Guenter Roeck > Fixes: 028474876f47 ("powerpc/32: prepare for CONFIG_VMAP_STACK") Tested-by: Guenter Roeck > --- > arch/powerpc/kernel/entry_32.S | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S > index 77abbc34bbe0..0713daa651d9 100644 > --- a/arch/powerpc/kernel/entry_32.S > +++ b/arch/powerpc/kernel/entry_32.S > @@ -214,7 +214,7 @@ transfer_to_handler_cont: > * To speed up the syscall path where interrupts stay on, let's check > * first if we are changing the MSR value at all. > */ > - tophys(r12, r1) > + tophys_novmstack r12, r1 > lwz r12,_MSR(r12) > andi. r12,r12,MSR_EE > bne 1f > -- > 2.25.0 >