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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CEDA6C77B61 for ; Fri, 28 Apr 2023 04:32:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345314AbjD1EcE (ORCPT ); Fri, 28 Apr 2023 00:32:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40222 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230350AbjD1EcC (ORCPT ); Fri, 28 Apr 2023 00:32:02 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB7DD1FF0 for ; Thu, 27 Apr 2023 21:32:01 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6A69163F67 for ; Fri, 28 Apr 2023 04:32:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 99E67C433D2; Fri, 28 Apr 2023 04:32:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1682656320; bh=NbRkJRYRrpSanpZI8cnamGI71x8F04vsDkhzvRB4Gp8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=lfwEE9QdlySRC1qEQyYl5zf60kVtzOpNyxov7QyrG66FbdDqXQ83+JvqfybDQvhQP 5hHe7QWmvRNHQ88r7rT8ug68vvsJSQfuRE+U+jSDzeiYcmlCO8NSGZJorRFUkRCybT khYetLHwj6Qzo73fJHkUpW8GzQqa5E/arrzyiwNYj+noMGG+f/tqufA5JBZLoqYEzu roj+UWNRThw6G7UnNgb0KTDA0fgxrR/A/XwV8X4VFkKQX0tYb3p3JXfV30iZvDyAwp biUCLn0FrRRLrMyhM04YpGNC9WjDnWtnjGB7d336CtEiWmamQJ1iTaRt+ND5GW3/mb o/v9MXrgcEXhg== Date: Thu, 27 Apr 2023 21:31:58 -0700 From: Josh Poimboeuf To: Oleg Nesterov Cc: Peter Zijlstra , Thomas Gleixner , Vernon Lovejoy , linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86/show_trace_log_lvl: ensure stack pointer is aligned, again Message-ID: <20230428043158.r5omehiaqawcac2y@treble> References: <20230427140054.GA17800@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20230427140054.GA17800@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 27, 2023 at 04:00:54PM +0200, Oleg Nesterov wrote: > diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c > index 0bf6779187dd..71ab445a29c3 100644 > --- a/arch/x86/kernel/dumpstack.c > +++ b/arch/x86/kernel/dumpstack.c > @@ -214,6 +214,7 @@ static void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs, > * - hardirq stack > * - entry stack > */ > + stack = PTR_ALIGN(stack, sizeof(long)); > for ( ; stack; stack = PTR_ALIGN(stack_info.next_sp, sizeof(long))) { > const char *stack_name; Seems reasonable, though 'stack' is already initialized a few lines above this, so it would be cleaner to do the PTR_ALIGN then. Or even better, just move it all to the for loop: for (stack = PTR_ALIGN(stack ? : get_stack_pointer(task, regs)); stack; stack = PTR_ALIGN(stack_info.next_sp, sizeof(long))) { -- Josh