From patchwork Wed Jul 17 08:06:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11047391 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 97E086C5 for ; Wed, 17 Jul 2019 07:50:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8D56A285A4 for ; Wed, 17 Jul 2019 07:50:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7E355286FF; Wed, 17 Jul 2019 07:50:31 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id 9DD0A285A4 for ; Wed, 17 Jul 2019 07:50:30 +0000 (UTC) Received: (qmail 1116 invoked by uid 550); 17 Jul 2019 07:49:39 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 32561 invoked from network); 17 Jul 2019 07:49:36 -0000 From: Jason Yan To: , , , , , , , , CC: , , , , , , Jason Yan Subject: [RFC PATCH 05/10] powerpc/fsl_booke/32: introduce reloc_kernel_entry() helper Date: Wed, 17 Jul 2019 16:06:16 +0800 Message-ID: <20190717080621.40424-6-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20190717080621.40424-1-yanaijie@huawei.com> References: <20190717080621.40424-1-yanaijie@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.28] X-CFilter-Loop: Reflected X-Virus-Scanned: ClamAV using ClamSMTP Add a new helper reloc_kernel_entry() to jump back to the start of the new kernel. After we put the new kernel in a randomized place we can use this new helper to enter the kernel and begin to relocate again. Signed-off-by: Jason Yan Cc: Diana Craciun Cc: Michael Ellerman Cc: Christophe Leroy Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Nicholas Piggin Cc: Kees Cook --- arch/powerpc/kernel/head_fsl_booke.S | 16 ++++++++++++++++ arch/powerpc/mm/mmu_decl.h | 1 + 2 files changed, 17 insertions(+) diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S index a57d44638031..ce40f96dae20 100644 --- a/arch/powerpc/kernel/head_fsl_booke.S +++ b/arch/powerpc/kernel/head_fsl_booke.S @@ -1144,6 +1144,22 @@ _GLOBAL(create_tlb_entry) sync blr +/* + * Return to the start of the relocated kernel and run again + * r3 - virtual address of fdt + * r4 - entry of the kernel + */ +_GLOBAL(reloc_kernel_entry) + mfmsr r7 + li r8,(MSR_IS | MSR_DS) + andc r7,r7,r8 + + mtspr SPRN_SRR0,r4 + mtspr SPRN_SRR1,r7 + isync + sync + rfi + /* * Create a tlb entry with the same effective and physical address as * the tlb entry used by the current running code. But set the TS to 1. diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h index d7737cf97cee..dae8e9177574 100644 --- a/arch/powerpc/mm/mmu_decl.h +++ b/arch/powerpc/mm/mmu_decl.h @@ -143,6 +143,7 @@ extern void adjust_total_lowmem(void); extern int switch_to_as1(void); extern void restore_to_as0(int esel, int offset, void *dt_ptr, int bootcpu); extern void create_tlb_entry(phys_addr_t phys, unsigned long virt, int entry); +extern void reloc_kernel_entry(void *fdt, int addr); #endif extern void loadcam_entry(unsigned int index); extern void loadcam_multi(int first_idx, int num, int tmp_idx);