From patchwork Thu May 27 15:05:16 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12284541 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=-16.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 7CCE8C4707F for ; Thu, 27 May 2021 15:05:49 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 28574613AB for ; Thu, 27 May 2021 15:05:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 28574613AB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=soleen.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 32F076B007D; Thu, 27 May 2021 11:05:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 304CA6B007E; Thu, 27 May 2021 11:05:43 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 097B96B0080; Thu, 27 May 2021 11:05:43 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0243.hostedemail.com [216.40.44.243]) by kanga.kvack.org (Postfix) with ESMTP id C4CDA6B007D for ; Thu, 27 May 2021 11:05:42 -0400 (EDT) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 60AFF181AEF1F for ; Thu, 27 May 2021 15:05:42 +0000 (UTC) X-FDA: 78187335324.26.3EC9391 Received: from mail-qv1-f43.google.com (mail-qv1-f43.google.com [209.85.219.43]) by imf06.hostedemail.com (Postfix) with ESMTP id 0AF02C005A08 for ; Thu, 27 May 2021 15:05:33 +0000 (UTC) Received: by mail-qv1-f43.google.com with SMTP id 5so276979qvk.0 for ; Thu, 27 May 2021 08:05:41 -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=WOdTNCc8/+vKdXFWJvALf/5jcbGhRyKjqHuE0XK9ac4=; b=d8BkTIMDubNMKo8lhGcNu7AKdRus5J2M4TufcGSW4HtAeu3NbJ3XThPB66dQ+1m9p4 uQSN6tv4/0GLeQQUYYLvH9KTMD/3Y0ymqQQJUncGSGi7O+XI9dAh+bjI/F2JTBUYDI/b hG56Miopzkxf4OQah6VFcnupnjMDqnyYzxqclfNuueFAlJIXCIk/mUQkSy0l9hy7LZ63 8t5Zl2QIKW2FphA5noBR5hutyqZWAAE7ORfjV0j8Vn4IoOBLjWbakCjpSu+mbfcwra9P 9PA5A7XXtZhKASA48HUe+DjXCCyoKtyblRuv7GcVXybzYhpFeowUdCednMkzMNvzqc3m sUNw== 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=WOdTNCc8/+vKdXFWJvALf/5jcbGhRyKjqHuE0XK9ac4=; b=NJent8Gsa6PBoZT/8Ticf/SPy00148KtPqBl2DmiFVCreqvkBlXnNYbGI6DbDpxh31 eTbqLmKMjaOUm8fA9XMKRmhd5jFYSxIkYBPJg5n7oHTbnybxbAzydaAQ+JEzwodHbUHb 56Q1492mteC5CEa2e7WIhyVfEKHA3+mJK7auu68GxzAIQDuOdg1fVO6LQ8ueVIVdUihA ovCBz6OfOltql/IF2ntsyvwDBRH8+zQ2wP8Bm1//gwrOdW8Ty+G4W6mzXhGAH0qMQTZA lPmT1J4XazO082UziEcZ5pH/hpH07XN0ReJP9CIkGw9ZxdlIgN4QaS6PkHhNTWqaqXpg JoVg== X-Gm-Message-State: AOAM531Cns1eQsDiVuUOC9NhJ6OK7TcPo5Xf1zvJd7jR1xX+JdbJdE3n WOcjv4LuJ6xQe/NnD8TfqwN8Ww== X-Google-Smtp-Source: ABdhPJxuuInT5boY5wx2h9r0mi/iNoeH4rIqWoxJwXXRJPR79arNDGrkhRpZr8NydkZli6xNGukztQ== X-Received: by 2002:ad4:4810:: with SMTP id g16mr4197984qvy.21.1622127941083; Thu, 27 May 2021 08:05:41 -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 x10sm1447468qkh.124.2021.05.27.08.05.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 27 May 2021 08:05:40 -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 08/18] arm64: kexec: skip relocation code for inplace kexec Date: Thu, 27 May 2021 11:05:16 -0400 Message-Id: <20210527150526.271941-9-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210527150526.271941-1-pasha.tatashin@soleen.com> References: <20210527150526.271941-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=soleen.com header.s=google header.b=d8BkTIMD; dmarc=none; spf=pass (imf06.hostedemail.com: domain of pasha.tatashin@soleen.com designates 209.85.219.43 as permitted sender) smtp.mailfrom=pasha.tatashin@soleen.com X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 0AF02C005A08 X-Stat-Signature: hpnru49z7xak6cry3z1knga145qpbwwb X-HE-Tag: 1622127933-793451 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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 3a034bc25709..bde623805866 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -139,21 +139,23 @@ 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. */ __flush_dcache_area(reloc_code, arm64_relocate_new_kernel_size); flush_icache_range((uintptr_t)reloc_code, (uintptr_t)reloc_code + arm64_relocate_new_kernel_size); + kexec_list_flush(kimage); + kexec_image_info(kimage); return 0; } @@ -180,19 +182,25 @@ 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_callable(), 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