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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 4F1CFC4338F for ; Mon, 2 Aug 2021 21:54:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3DAFE60FA0 for ; Mon, 2 Aug 2021 21:54:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232757AbhHBVyf (ORCPT ); Mon, 2 Aug 2021 17:54:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47276 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232882AbhHBVy2 (ORCPT ); Mon, 2 Aug 2021 17:54:28 -0400 Received: from mail-qk1-x72c.google.com (mail-qk1-x72c.google.com [IPv6:2607:f8b0:4864:20::72c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C6CEBC061796 for ; Mon, 2 Aug 2021 14:54:18 -0700 (PDT) Received: by mail-qk1-x72c.google.com with SMTP id 190so18086074qkk.12 for ; Mon, 02 Aug 2021 14:54:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=ySRVVRwC++hMLjkNftECyAUjQh43zsO4xteYxz9kO+M=; b=dDf0vz0iWjVamQXhs2vdDdV8GxpuCrMHeOrVcKatUZm8kDuGj8aeCscvU0ZKD0PR0u P3pwTsllBPlz2qGvsHN3dUnYVn9dSEo6LBJP4H0RtxYomoXuhtxjmIISfIRQ193rnuhP 7enai/reMUqp8BRJ5yUgJrsJ1VF4UhhHchvnJ/ktN2mn4+i6gV4H1OPJh0qz01OH1/6B OQvr+N3zf28VJq15xRpdvv1UhQgnEzM4s2IEP+eICABab0xDNAQhm8X2FjUx1acmwCXi Yh399GttIvMrf46wXZgEWsv0Srz2KGWWLNr48vP5KF4aBEf9kYJIUn7GwYCoX3x/AROl HE1Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=ySRVVRwC++hMLjkNftECyAUjQh43zsO4xteYxz9kO+M=; b=WoVqUrm/20ystWa6/bwqQ21kR1ZPoJEFPO8kzxcqvbmOy9jrqNtnDaEFm0XgqZp0Tt En4xMAQDMXFmcqwijel4tKLFJmBHSldcYY1rIia7xCahvSUdecGG3N+A1Z/7JT/KELEo us1iqOkkhOURYDyOHkxtFx5Mui1RB+ehrqvQCU0J+GluT8hR0h+LVeCOzoNufJJ+edVl XkAiNX1FSrpMZB5Ni9R2JVlW6XQuefjXP6ej5tv3sSRtbS/+OVx+uYmxvY7jQ50RnWIH 0S1XxJbx5ivNerRyplD7m5tl1phWRh/vxRsOefgLYeHK8GhDzmAu3pRDkAZSZc/9gE1Q UnWg== X-Gm-Message-State: AOAM531raBqw5MEc1m1fBvoRpG++g9Omn+8wWiHcRVjaoneaTFuol/Ro NwTeQeqnMs476upJYMdyJrj/jw== X-Google-Smtp-Source: ABdhPJycxFDEqftDsNgLCqQw0liKmCH9habEesWjmQ0Ce5hXdnSfdBKjeqzPZ1g5aBX40OQ7MsZwFg== X-Received: by 2002:a05:620a:4d0:: with SMTP id 16mr17965487qks.430.1627941257981; Mon, 02 Aug 2021 14:54:17 -0700 (PDT) Received: from localhost.localdomain (c-73-69-118-222.hsd1.nh.comcast.net. [73.69.118.222]) by smtp.gmail.com with ESMTPSA id v11sm5479216qtc.0.2021.08.02.14.54.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 02 Aug 2021 14:54:17 -0700 (PDT) From: Pavel Tatashin To: pasha.tatashin@soleen.com, jmorris@namei.org, sashal@kernel.org, ebiederm@xmission.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, corbet@lwn.net, catalin.marinas@arm.com, will@kernel.org, linux-arm-kernel@lists.infradead.org, maz@kernel.org, james.morse@arm.com, vladimir.murzin@arm.com, matthias.bgg@gmail.com, linux-mm@kvack.org, mark.rutland@arm.com, steve.capper@arm.com, rfontana@redhat.com, tglx@linutronix.de, selindag@gmail.com, tyhicks@linux.microsoft.com, kernelfans@gmail.com, akpm@linux-foundation.org, madvenka@linux.microsoft.com Subject: [PATCH v16 05/15] arm64: kexec: skip relocation code for inplace kexec Date: Mon, 2 Aug 2021 17:53:58 -0400 Message-Id: <20210802215408.804942-6-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210802215408.804942-1-pasha.tatashin@soleen.com> References: <20210802215408.804942-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In case of kdump or when segments are already in place the relocation is not needed, therefore the setup of relocation function and call to it can be skipped. Signed-off-by: Pavel Tatashin Suggested-by: James Morse --- arch/arm64/kernel/machine_kexec.c | 34 ++++++++++++++++++----------- arch/arm64/kernel/relocate_kernel.S | 3 --- 2 files changed, 21 insertions(+), 16 deletions(-) diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c index b6d5a02cba2e..7f1cb5a2a463 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -144,16 +144,16 @@ int machine_kexec_post_load(struct kimage *kimage) { void *reloc_code = page_to_virt(kimage->control_code_page); - /* If in place flush new kernel image, else flush lists and buffers */ - if (kimage->head & IND_DONE) + /* If in place, relocation is not used, only flush next kernel */ + if (kimage->head & IND_DONE) { kexec_segment_flush(kimage); - else - kexec_list_flush(kimage); + kexec_image_info(kimage); + return 0; + } memcpy(reloc_code, arm64_relocate_new_kernel, arm64_relocate_new_kernel_size); kimage->arch.kern_reloc = __pa(reloc_code); - kexec_image_info(kimage); /* Flush the reloc_code in preparation for its execution. */ dcache_clean_inval_poc((unsigned long)reloc_code, @@ -162,6 +162,8 @@ int machine_kexec_post_load(struct kimage *kimage) icache_inval_pou((uintptr_t)reloc_code, (uintptr_t)reloc_code + arm64_relocate_new_kernel_size); + kexec_list_flush(kimage); + kexec_image_info(kimage); return 0; } @@ -188,19 +190,25 @@ void machine_kexec(struct kimage *kimage) local_daif_mask(); /* - * cpu_soft_restart will shutdown the MMU, disable data caches, then - * transfer control to the kern_reloc which contains a copy of - * the arm64_relocate_new_kernel routine. arm64_relocate_new_kernel - * uses physical addressing to relocate the new image to its final - * position and transfers control to the image entry point when the - * relocation is complete. + * Both restart and cpu_soft_restart will shutdown the MMU, disable data + * caches. However, restart will start new kernel or purgatory directly, + * cpu_soft_restart will transfer control to arm64_relocate_new_kernel * In kexec case, kimage->start points to purgatory assuming that * kernel entry and dtb address are embedded in purgatory by * userspace (kexec-tools). * In kexec_file case, the kernel starts directly without purgatory. */ - cpu_soft_restart(kimage->arch.kern_reloc, kimage->head, kimage->start, - kimage->arch.dtb_mem); + if (kimage->head & IND_DONE) { + typeof(__cpu_soft_restart) *restart; + + cpu_install_idmap(); + restart = (void *)__pa_symbol(function_nocfi(__cpu_soft_restart)); + restart(is_hyp_nvhe(), kimage->start, kimage->arch.dtb_mem, + 0, 0); + } else { + cpu_soft_restart(kimage->arch.kern_reloc, kimage->head, + kimage->start, kimage->arch.dtb_mem); + } BUG(); /* Should never get here. */ } diff --git a/arch/arm64/kernel/relocate_kernel.S b/arch/arm64/kernel/relocate_kernel.S index b78ea5de97a4..8058fabe0a76 100644 --- a/arch/arm64/kernel/relocate_kernel.S +++ b/arch/arm64/kernel/relocate_kernel.S @@ -32,8 +32,6 @@ SYM_CODE_START(arm64_relocate_new_kernel) mov x16, x0 /* x16 = kimage_head */ mov x14, xzr /* x14 = entry ptr */ mov x13, xzr /* x13 = copy dest */ - /* Check if the new image needs relocation. */ - tbnz x16, IND_DONE_BIT, .Ldone raw_dcache_line_size x15, x1 /* x15 = dcache line size */ .Lloop: and x12, x16, PAGE_MASK /* x12 = addr */ @@ -65,7 +63,6 @@ SYM_CODE_START(arm64_relocate_new_kernel) .Lnext: ldr x16, [x14], #8 /* entry = *ptr++ */ tbz x16, IND_DONE_BIT, .Lloop /* while (!(entry & DONE)) */ -.Ldone: /* wait for writes from copy_page to finish */ dsb nsh ic iallu -- 2.25.1