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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 E0F9FC3A5A3 for ; Tue, 27 Aug 2019 23:05:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BD513214DA for ; Tue, 27 Aug 2019 23:05:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726444AbfH0XFT (ORCPT ); Tue, 27 Aug 2019 19:05:19 -0400 Received: from baldur.buserror.net ([165.227.176.147]:48606 "EHLO baldur.buserror.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725992AbfH0XFT (ORCPT ); Tue, 27 Aug 2019 19:05:19 -0400 X-Greylist: delayed 3026 seconds by postgrey-1.27 at vger.kernel.org; Tue, 27 Aug 2019 19:05:18 EDT Received: from [2601:449:8400:7293:12bf:48ff:fe84:c9a0] (helo=home.buserror.net) by baldur.buserror.net with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1i2jd4-0005yb-Kk; Tue, 27 Aug 2019 17:07:56 -0500 Date: Tue, 27 Aug 2019 17:07:52 -0500 From: Scott Wood To: Jason Yan Cc: mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org, diana.craciun@nxp.com, christophe.leroy@c-s.fr, benh@kernel.crashing.org, paulus@samba.org, npiggin@gmail.com, keescook@chromium.org, kernel-hardening@lists.openwall.com, wangkefeng.wang@huawei.com, linux-kernel@vger.kernel.org, jingxiangfeng@huawei.com, zhaohongjiang@huawei.com, thunder.leizhen@huawei.com, fanchengyang@huawei.com, yebin10@huawei.com Message-ID: <20190827220752.GA17757@home.buserror.net> References: <20190809100800.5426-1-yanaijie@huawei.com> <20190809100800.5426-5-yanaijie@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190809100800.5426-5-yanaijie@huawei.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-SA-Exim-Connect-IP: 2601:449:8400:7293:12bf:48ff:fe84:c9a0 X-SA-Exim-Rcpt-To: yanaijie@huawei.com, mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org, diana.craciun@nxp.com, christophe.leroy@c-s.fr, benh@kernel.crashing.org, paulus@samba.org, npiggin@gmail.com, keescook@chromium.org, kernel-hardening@lists.openwall.com, wangkefeng.wang@huawei.com, linux-kernel@vger.kernel.org, jingxiangfeng@huawei.com, zhaohongjiang@huawei.com, thunder.leizhen@huawei.com, fanchengyang@huawei.com, yebin10@huawei.com X-SA-Exim-Mail-From: oss@buserror.net Subject: Re: [PATCH v6 04/12] powerpc/fsl_booke/32: introduce create_tlb_entry() helper X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000) X-SA-Exim-Scanned: Yes (on baldur.buserror.net) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 09, 2019 at 06:07:52PM +0800, Jason Yan wrote: > Add a new helper create_tlb_entry() to create a tlb entry by the virtual > and physical address. This is a preparation to support boot kernel at a > randomized address. > > 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 > Reviewed-by: Christophe Leroy > Reviewed-by: Diana Craciun > Tested-by: Diana Craciun > --- > arch/powerpc/kernel/head_fsl_booke.S | 29 ++++++++++++++++++++++++++++ > arch/powerpc/mm/mmu_decl.h | 1 + > 2 files changed, 30 insertions(+) > > diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S > index adf0505dbe02..04d124fee17d 100644 > --- a/arch/powerpc/kernel/head_fsl_booke.S > +++ b/arch/powerpc/kernel/head_fsl_booke.S > @@ -1114,6 +1114,35 @@ __secondary_hold_acknowledge: > .long -1 > #endif > > +/* > + * Create a 64M tlb by address and entry > + * r3/r4 - physical address > + * r5 - virtual address > + * r6 - entry > + */ > +_GLOBAL(create_tlb_entry) This function is broadly named but contains various assumptions about the entry being created. I'd just call it create_kaslr_tlb_entry. > + lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */ > + rlwimi r7,r6,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r6) */ > + mtspr SPRN_MAS0,r7 /* Write MAS0 */ > + > + lis r6,(MAS1_VALID|MAS1_IPROT)@h > + ori r6,r6,(MAS1_TSIZE(BOOK3E_PAGESZ_64M))@l > + mtspr SPRN_MAS1,r6 /* Write MAS1 */ > + > + lis r6,MAS2_EPN_MASK(BOOK3E_PAGESZ_64M)@h > + ori r6,r6,MAS2_EPN_MASK(BOOK3E_PAGESZ_64M)@l > + and r6,r6,r5 > + ori r6,r6,MAS2_M@l > + mtspr SPRN_MAS2,r6 /* Write MAS2(EPN) */ > + > + ori r8,r4,(MAS3_SW|MAS3_SR|MAS3_SX) > + mtspr SPRN_MAS3,r8 /* Write MAS3(RPN) */ > + > + tlbwe /* Write TLB */ > + isync > + sync > + blr Should set MAS7 under MMU_FTR_BIG_PHYS (or CONFIG_PHYS_64BIT if it's too early for features) -- even if relocatable kernels over 4GiB aren't supported (I don't remember if they work or not), MAS7 might be non-zero on entry. And the function claims to take a 64-bit phys addr as input... MAS2_M should be MAS2_M_IF_NEEDED to match other kmem tlb entries. -Scott