From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f70.google.com (mail-pg0-f70.google.com [74.125.83.70]) by kanga.kvack.org (Postfix) with ESMTP id 17A28280405 for ; Mon, 21 Aug 2017 11:29:35 -0400 (EDT) Received: by mail-pg0-f70.google.com with SMTP id q3so72844152pgr.3 for ; Mon, 21 Aug 2017 08:29:35 -0700 (PDT) Received: from mga06.intel.com (mga06.intel.com. [134.134.136.31]) by mx.google.com with ESMTPS id t76si7342978pgc.539.2017.08.21.08.29.33 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 21 Aug 2017 08:29:33 -0700 (PDT) From: "Kirill A. Shutemov" Subject: [PATCHv5 13/19] x86/mm: Make early boot code support boot-time switching of paging modes Date: Mon, 21 Aug 2017 18:29:10 +0300 Message-Id: <20170821152916.40124-14-kirill.shutemov@linux.intel.com> In-Reply-To: <20170821152916.40124-1-kirill.shutemov@linux.intel.com> References: <20170821152916.40124-1-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Linus Torvalds , x86@kernel.org, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Cc: Andrew Morton , Andy Lutomirski , Dmitry Safonov , Cyrill Gorcunov , Borislav Petkov , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Early boot code, that setup page table should be able to initialize page tables for both 4- and 5-level paging modes. Signed-off-by: Kirill A. Shutemov --- arch/x86/kernel/head64.c | 33 +++++++++++++++++++++------------ arch/x86/kernel/head_64.S | 10 ++++------ 2 files changed, 25 insertions(+), 18 deletions(-) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index f013b0732c96..8a44b3d06261 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -74,13 +74,13 @@ 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) +static bool __head check_la57_support(unsigned long physaddr) { if (native_cpuid_eax(0) < 7) - return; + return false; if (!(native_cpuid_ecx(7) & (1 << (X86_FEATURE_LA57 & 31)))) - return; + return false; *fixup_int(&pgtable_l5_enabled, physaddr) = 1; *fixup_int(&pgdir_shift, physaddr) = 48; @@ -89,24 +89,28 @@ static void __head check_la57_support(unsigned long physaddr) *fixup_long(&vmalloc_base, physaddr) = __VMALLOC_BASE57; *fixup_long(&vmemmap_base, physaddr) = __VMEMMAP_BASE57; - return; + return true; } #else -static void __head check_la57_support(unsigned long physaddr) {} +static bool __head check_la57_support(unsigned long physaddr) +{ + return false; +} #endif unsigned long __head __startup_64(unsigned long physaddr, struct boot_params *bp) { - unsigned long load_delta; + unsigned long load_delta, *p; unsigned long pgtable_flags; pgdval_t *pgd; p4dval_t *p4d; pudval_t *pud; pmdval_t *pmd, pmd_entry; + bool la57; int i; - check_la57_support(physaddr); + la57 = check_la57_support(physaddr); /* Is the address too large? */ if (physaddr >> MAX_PHYSMEM_BITS) @@ -131,9 +135,14 @@ unsigned long __head __startup_64(unsigned long physaddr, /* Fixup the physical addresses in the page table */ pgd = fixup_pointer(&early_top_pgt, physaddr); - pgd[pgd_index(__START_KERNEL_map)] += load_delta; - - if (IS_ENABLED(CONFIG_X86_5LEVEL)) { + p = pgd + pgd_index(__START_KERNEL_map); + if (la57) + *p = (unsigned long)level4_kernel_pgt; + else + *p = (unsigned long)level3_kernel_pgt; + *p += _PAGE_TABLE_NOENC - __START_KERNEL_map + load_delta; + + if (la57) { p4d = fixup_pointer(&level4_kernel_pgt, physaddr); p4d[511] += load_delta; } @@ -156,7 +165,7 @@ unsigned long __head __startup_64(unsigned long physaddr, pmd = fixup_pointer(early_dynamic_pgts[next_early_pgt++], physaddr); pgtable_flags = _KERNPG_TABLE_NOENC + sme_get_me_mask(); - if (IS_ENABLED(CONFIG_X86_5LEVEL)) { + if (la57) { p4d = fixup_pointer(early_dynamic_pgts[next_early_pgt++], physaddr); i = (physaddr >> PGDIR_SHIFT) % PTRS_PER_PGD; @@ -253,7 +262,7 @@ int __init __early_make_pgtable(unsigned long address, pmdval_t pmd) * critical -- __PAGE_OFFSET would point us back into the dynamic * range and we might end up looping forever... */ - if (!IS_ENABLED(CONFIG_X86_5LEVEL)) + if (!pgtable_l5_enabled) p4d_p = pgd_p; else if (pgd) p4d_p = (p4dval_t *)((pgd & PTE_PFN_MASK) + __START_KERNEL_map - phys_base); diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index a8409cd23b35..49f8bb43d107 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -121,7 +121,10 @@ ENTRY(secondary_startup_64) /* Enable PAE mode, PGE and LA57 */ movl $(X86_CR4_PAE | X86_CR4_PGE), %ecx #ifdef CONFIG_X86_5LEVEL + testl $1, pgtable_l5_enabled(%rip) + jz 1f orl $X86_CR4_LA57, %ecx +1: #endif movq %rcx, %cr4 @@ -350,12 +353,7 @@ GLOBAL(name) __INITDATA NEXT_PAGE(early_top_pgt) - .fill 511,8,0 -#ifdef CONFIG_X86_5LEVEL - .quad level4_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE_NOENC -#else - .quad level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE_NOENC -#endif + .fill 512,8,0 NEXT_PAGE(early_dynamic_pgts) .fill 512*EARLY_DYNAMIC_PAGE_TABLES,8,0 -- 2.14.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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