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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 074A1C4321E for ; Sun, 27 Nov 2022 12:54:26 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4NKpTD4qTmz3f9r for ; Sun, 27 Nov 2022 23:54:24 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20210112 header.b=FgVEsUwj; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gmail.com (client-ip=2607:f8b0:4864:20::1034; helo=mail-pj1-x1034.google.com; envelope-from=npiggin@gmail.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20210112 header.b=FgVEsUwj; dkim-atps=neutral Received: from mail-pj1-x1034.google.com (mail-pj1-x1034.google.com [IPv6:2607:f8b0:4864:20::1034]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4NKpN94rk4z3cJM for ; Sun, 27 Nov 2022 23:50:01 +1100 (AEDT) Received: by mail-pj1-x1034.google.com with SMTP id t11-20020a17090a024b00b0021932afece4so602671pje.5 for ; Sun, 27 Nov 2022 04:50:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=WRuFoJst6qFyhTCk1lHltjd/22AEakekbUAT3ErVngw=; b=FgVEsUwjeaZp1Hh8Bdcytqy8C3hANEzdOKzAnjBLCBnxGP6D67aG1Lwplu9CmrScYt mNCYxE3+u/6efo4MFXVPTsHA3asupn9S0ro41II5gyNnhJ5ruLf1OKc1jXJKpv12s2l3 4UfzHMZ1jv2E7W+HakJ7lpF9b1j8bK0NvgJSRZvsz6+IFjliRz6GYmXu2YYksNejP1PQ Gh/RZ3x3kYfzNuDaYWrIb9jYqO52t2bC7nlUzGyl5CJB+M6QyxkM0KxSd0M/GnucekYF DWZ+qbrCw2JjUPN9D6E0aLfA+rRJK2sFqEH0Dg+jNnpI2nGiLv24qQ+BPvloSYxXZFsO Qffw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=WRuFoJst6qFyhTCk1lHltjd/22AEakekbUAT3ErVngw=; b=UJNLV+ikaTzGbM6OciFoBl7d5kZngXkPTX0hmXQiguGMH/zb0n9Ko5IMXZX6QIwne/ fNvEYEV/G3v9GhkmkywRLYUIZdONodiDO2ckF5JXcqJWT8gEdmbOk9z9UtKYylDMKrgy Zmt50GenoosqZASkvGShS1NYKo13N144n1xVUv2bfl5t1mRSTVM+cDrE5YVUKs/pM9Hn uNwvWvXrj2Y+KnSEL9xWHF2gjR87z7e3Pwyy+g2e+wac13h4RX+zOxLL+CnFWiojbZBN c/jZTldTWY4f6dsoRFthnkmNicNOMOKZzV4d7+ScyLOO97WDjzdqpq7jbpsQ5+7H1fEb cMcg== X-Gm-Message-State: ANoB5pkWleXtsb4M+Efk+jg8wpcXBLrBSrQUfzpPEcMoi6cxaziknY0h 2nenQ62vWaMzw2FU7KSlhKAJi0wpoTrRww== X-Google-Smtp-Source: AA0mqf4W2dWebeWcmu+jb4SDKL0XED45ljxgllkj+JQrIaxWoN3z8wytJLIrNC5OLjlWzNddEpzcvw== X-Received: by 2002:a17:903:41c8:b0:17d:b9c:cd64 with SMTP id u8-20020a17090341c800b0017d0b9ccd64mr29242906ple.40.1669553398888; Sun, 27 Nov 2022 04:49:58 -0800 (PST) Received: from bobo.ozlabs.ibm.com ([220.240.231.60]) by smtp.gmail.com with ESMTPSA id q13-20020a63e20d000000b00473c36ea150sm5102287pgh.92.2022.11.27.04.49.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 27 Nov 2022 04:49:58 -0800 (PST) From: Nicholas Piggin To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH 04/17] powerpc: Rearrange copy_thread child stack creation Date: Sun, 27 Nov 2022 22:49:29 +1000 Message-Id: <20221127124942.1665522-5-npiggin@gmail.com> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20221127124942.1665522-1-npiggin@gmail.com> References: <20221127124942.1665522-1-npiggin@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nicholas Piggin Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" This makes it a bit clearer where the stack frame is created, and will allow easier use of some of the stack offset constants in a later change. Signed-off-by: Nicholas Piggin --- arch/powerpc/kernel/process.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 67da147fe34d..acfa197fb2df 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1726,13 +1726,16 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) klp_init_thread_info(p); + /* Create initial stack frame. */ + sp -= (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD); + ((unsigned long *)sp)[0] = 0; + /* Copy registers */ - sp -= sizeof(struct pt_regs); - childregs = (struct pt_regs *) sp; + childregs = (struct pt_regs *)(sp + STACK_FRAME_OVERHEAD); if (unlikely(args->fn)) { /* kernel thread */ memset(childregs, 0, sizeof(struct pt_regs)); - childregs->gpr[1] = sp + sizeof(struct pt_regs); + childregs->gpr[1] = sp + (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD); /* function */ if (args->fn) childregs->gpr[14] = ppc_function_entry((void *)args->fn); @@ -1767,7 +1770,6 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) f = ret_from_fork; } childregs->msr &= ~(MSR_FP|MSR_VEC|MSR_VSX); - sp -= STACK_FRAME_OVERHEAD; /* * The way this works is that at some point in the future @@ -1777,7 +1779,6 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) * do some house keeping and then return from the fork or clone * system call, using the stack frame created above. */ - ((unsigned long *)sp)[0] = 0; sp -= sizeof(struct pt_regs); kregs = (struct pt_regs *) sp; sp -= STACK_FRAME_OVERHEAD; -- 2.37.2