From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934909AbeBPLDd (ORCPT ); Fri, 16 Feb 2018 06:03:33 -0500 Received: from terminus.zytor.com ([198.137.202.136]:55709 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934609AbeBPLDb (ORCPT ); Fri, 16 Feb 2018 06:03:31 -0500 Date: Fri, 16 Feb 2018 02:51:59 -0800 From: "tip-bot for Kirill A. Shutemov" Message-ID: Cc: dwmw2@infradead.org, tglx@linutronix.de, arjan@linux.intel.com, luto@kernel.org, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, bp@suse.de, peterz@infradead.org, dan.j.williams@intel.com, jpoimboe@redhat.com, kirill.shutemov@linux.intel.com, dave.hansen@linux.intel.com, hpa@zytor.com, mingo@kernel.org Reply-To: luto@kernel.org, arjan@linux.intel.com, dwmw2@infradead.org, tglx@linutronix.de, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, jpoimboe@redhat.com, dan.j.williams@intel.com, peterz@infradead.org, bp@suse.de, mingo@kernel.org, hpa@zytor.com, kirill.shutemov@linux.intel.com, dave.hansen@linux.intel.com In-Reply-To: <20180214182542.69302-2-kirill.shutemov@linux.intel.com> References: <20180214182542.69302-2-kirill.shutemov@linux.intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/mm] x86/mm: Initialize 'pgtable_l5_enabled' at boot-time Git-Commit-ID: 4c2b4058ab32581931c2caf760b689fd4b019a87 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 4c2b4058ab32581931c2caf760b689fd4b019a87 Gitweb: https://git.kernel.org/tip/4c2b4058ab32581931c2caf760b689fd4b019a87 Author: Kirill A. Shutemov AuthorDate: Wed, 14 Feb 2018 21:25:34 +0300 Committer: Ingo Molnar CommitDate: Fri, 16 Feb 2018 10:48:46 +0100 x86/mm: Initialize 'pgtable_l5_enabled' at boot-time 'pgtable_l5_enabled' indicates which paging mode we are using. We need to initialize it at boot-time according to machine capability. Signed-off-by: Kirill A. Shutemov Cc: Andy Lutomirski Cc: Arjan van de Ven Cc: Borislav Petkov Cc: Dan Williams Cc: Dave Hansen Cc: David Woodhouse Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20180214182542.69302-2-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar --- arch/x86/boot/compressed/kaslr.c | 8 +++++++- arch/x86/kernel/head64.c | 24 +++++++++++++++++++++++- 2 files changed, 30 insertions(+), 2 deletions(-) diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index b18e8f9..d02a838 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -47,7 +47,7 @@ #include #ifdef CONFIG_X86_5LEVEL -unsigned int pgtable_l5_enabled __ro_after_init = 1; +unsigned int pgtable_l5_enabled __ro_after_init; unsigned int pgdir_shift __ro_after_init = 48; unsigned int ptrs_per_p4d __ro_after_init = 512; #endif @@ -729,6 +729,12 @@ void choose_random_location(unsigned long input, return; } +#ifdef CONFIG_X86_5LEVEL + if (__read_cr4() & X86_CR4_LA57) { + pgtable_l5_enabled = 1; + } +#endif + boot_params->hdr.loadflags |= KASLR_FLAG; /* Prepare to add new identity pagetables on demand. */ diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 98b0ff4..ffb31c5 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -40,7 +40,7 @@ static unsigned int __initdata next_early_pgt; pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX); #ifdef CONFIG_X86_5LEVEL -unsigned int pgtable_l5_enabled __ro_after_init = 1; +unsigned int pgtable_l5_enabled __ro_after_init; EXPORT_SYMBOL(pgtable_l5_enabled); unsigned int pgdir_shift __ro_after_init = 48; EXPORT_SYMBOL(pgdir_shift); @@ -64,6 +64,26 @@ static void __head *fixup_pointer(void *ptr, unsigned long physaddr) return ptr - (void *)_text + (void *)physaddr; } +#ifdef CONFIG_X86_5LEVEL +static unsigned int __head *fixup_int(void *ptr, unsigned long physaddr) +{ + return fixup_pointer(ptr, physaddr); +} + +static void __head check_la57_support(unsigned long physaddr) +{ + if (native_cpuid_eax(0) < 7) + return; + + if (!(native_cpuid_ecx(7) & (1 << (X86_FEATURE_LA57 & 31)))) + return; + + *fixup_int(&pgtable_l5_enabled, physaddr) = 1; +} +#else +static void __head check_la57_support(unsigned long physaddr) {} +#endif + unsigned long __head __startup_64(unsigned long physaddr, struct boot_params *bp) { @@ -76,6 +96,8 @@ unsigned long __head __startup_64(unsigned long physaddr, int i; unsigned int *next_pgt_ptr; + check_la57_support(physaddr); + /* Is the address too large? */ if (physaddr >> MAX_PHYSMEM_BITS) for (;;);