Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753581AbcLFTM0 (ORCPT ); Tue, 6 Dec 2016 14:12:26 -0500 Received: from mail-qt0-f178.google.com ([209.85.216.178]:35847 "EHLO mail-qt0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751180AbcLFTMY (ORCPT ); Tue, 6 Dec 2016 14:12:24 -0500 Subject: Re: [PATCHv4 05/10] arm64: Use __pa_symbol for kernel symbols To: Mark Rutland References: <1480445729-27130-1-git-send-email-labbott@redhat.com> <1480445729-27130-6-git-send-email-labbott@redhat.com> <20161206170222.GE24177@leverpostej> Cc: Ard Biesheuvel , Will Deacon , Catalin Marinas , Christoffer Dall , Marc Zyngier , Lorenzo Pieralisi , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Marek Szyprowski , Joonsoo Kim , linux-arm-kernel@lists.infradead.org From: Laura Abbott Message-ID: <7408b896-f0c0-592c-2ae2-ca01b604aebb@redhat.com> Date: Tue, 6 Dec 2016 11:12:18 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <20161206170222.GE24177@leverpostej> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5648 Lines: 140 On 12/06/2016 09:02 AM, Mark Rutland wrote: > Hi, > > As a heads-up, it looks like this got mangled somewhere. In the hunk at > arch/arm64/mm/kasan_init.c:68, 'do' in the context became 'edo'. > Deleting the 'e' makes it apply. > Argh, this must have come in while editing the .patch before e-mailing. Sorry about that. > I think this is almost there; other than James's hibernate bug I only > see one real issue, and everything else is a minor nit. > > On Tue, Nov 29, 2016 at 10:55:24AM -0800, Laura Abbott wrote: >> __pa_symbol is technically the marco that should be used for kernel >> symbols. Switch to this as a pre-requisite for DEBUG_VIRTUAL which >> will do bounds checking. As part of this, introduce lm_alias, a >> macro which wraps the __va(__pa(...)) idiom used a few places to >> get the alias. > > I think the addition of the lm_alias() macro under include/mm should be > a separate preparatory patch. That way it's separate from the > arm64-specific parts, and more obvious to !arm64 people reviewing the > other parts. > I debated if it was more obvious to show how it was used in context vs a stand alone patch. I think you're right that for non-arm64 reviewers the separate patch would be easier to find. >> Signed-off-by: Laura Abbott >> --- >> v4: Stop calling __va early, conversion of a few more sites. I decided against >> wrapping the __p*d_populate calls into new functions since the call sites >> should be limited. >> --- >> arch/arm64/include/asm/kvm_mmu.h | 4 ++-- >> arch/arm64/include/asm/memory.h | 2 ++ >> arch/arm64/include/asm/mmu_context.h | 6 +++--- >> arch/arm64/include/asm/pgtable.h | 2 +- >> arch/arm64/kernel/acpi_parking_protocol.c | 2 +- >> arch/arm64/kernel/cpu-reset.h | 2 +- >> arch/arm64/kernel/cpufeature.c | 2 +- >> arch/arm64/kernel/hibernate.c | 13 +++++-------- >> arch/arm64/kernel/insn.c | 2 +- >> arch/arm64/kernel/psci.c | 2 +- >> arch/arm64/kernel/setup.c | 8 ++++---- >> arch/arm64/kernel/smp_spin_table.c | 2 +- >> arch/arm64/kernel/vdso.c | 4 ++-- >> arch/arm64/mm/init.c | 11 ++++++----- >> arch/arm64/mm/kasan_init.c | 21 +++++++++++++------- >> arch/arm64/mm/mmu.c | 32 +++++++++++++++++++------------ >> drivers/firmware/psci.c | 2 +- >> include/linux/mm.h | 4 ++++ >> 18 files changed, 70 insertions(+), 51 deletions(-) > > It looks like we need to make sure these (directly) include > for __pa_symbol() and lm_alias(), or there's some fragility, e.g. > > [mark@leverpostej:~/src/linux]% uselinaro 15.08 make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- -j10 -s > arch/arm64/kernel/psci.c: In function 'cpu_psci_cpu_boot': > arch/arm64/kernel/psci.c:48:50: error: implicit declaration of function '__pa_symbol' [-Werror=implicit-function-declaration] > int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa_symbol(secondary_entry)); > ^ > cc1: some warnings being treated as errors > make[1]: *** [arch/arm64/kernel/psci.o] Error 1 > make: *** [arch/arm64/kernel] Error 2 > make: *** Waiting for unfinished jobs.... > Right, I'll double check. >> --- a/arch/arm64/include/asm/memory.h >> +++ b/arch/arm64/include/asm/memory.h >> @@ -205,6 +205,8 @@ static inline void *phys_to_virt(phys_addr_t x) >> #define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x))) >> #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) >> #define virt_to_pfn(x) __phys_to_pfn(__virt_to_phys((unsigned long)(x))) >> +#define sym_to_pfn(x) __phys_to_pfn(__pa_symbol(x)) >> +#define lm_alias(x) __va(__pa_symbol(x)) > > As Catalin mentioned, we should be able to drop this copy of lm_alias(), > given we have the same in the core headers. > >> diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c >> index a2c2478..79cd86b 100644 >> --- a/arch/arm64/kernel/vdso.c >> +++ b/arch/arm64/kernel/vdso.c >> @@ -140,11 +140,11 @@ static int __init vdso_init(void) >> return -ENOMEM; >> >> /* Grab the vDSO data page. */ >> - vdso_pagelist[0] = pfn_to_page(PHYS_PFN(__pa(vdso_data))); >> + vdso_pagelist[0] = phys_to_page(__pa_symbol(vdso_data)); >> >> /* Grab the vDSO code pages. */ >> for (i = 0; i < vdso_pages; i++) >> - vdso_pagelist[i + 1] = pfn_to_page(PHYS_PFN(__pa(&vdso_start)) + i); >> + vdso_pagelist[i + 1] = pfn_to_page(PHYS_PFN(__pa_symbol(&vdso_start)) + i); > > I see you added sym_to_pfn(), which we can use here to keep this short > and legible. It might also be worth using a temporary pfn_t, e.g. > > pfn = sym_to_pfn(&vdso_start); > > for (i = 0; i < vdso_pages; i++) > vdso_pagelist[i + 1] = pfn_to_page(pfn + i); > Good idea. >> diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c >> index 8263429..9defbe2 100644 >> --- a/drivers/firmware/psci.c >> +++ b/drivers/firmware/psci.c >> @@ -383,7 +383,7 @@ static int psci_suspend_finisher(unsigned long index) >> u32 *state = __this_cpu_read(psci_power_state); >> >> return psci_ops.cpu_suspend(state[index - 1], >> - virt_to_phys(cpu_resume)); >> + __pa_symbol(cpu_resume)); >> } >> >> int psci_cpu_suspend_enter(unsigned long index) > > This should probably be its own patch since it's not under arch/arm64/. > Fine by me. > I'm happy for this to go via the arm64 tree with the rest regardless > (assuming Lorenzo has no objections). > > Thanks, > Mark. > Thanks, Laura