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 BF3FA6B000E for ; Wed, 14 Feb 2018 06:17:17 -0500 (EST) Received: by mail-pg0-f70.google.com with SMTP id i11so1744510pgq.10 for ; Wed, 14 Feb 2018 03:17:17 -0800 (PST) Received: from mga01.intel.com (mga01.intel.com. [192.55.52.88]) by mx.google.com with ESMTPS id e1-v6si2695518ple.154.2018.02.14.03.17.16 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 14 Feb 2018 03:17:16 -0800 (PST) From: "Kirill A. Shutemov" Subject: [PATCH 8/9] x86/mm: Make __VIRTUAL_MASK_SHIFT dynamic Date: Wed, 14 Feb 2018 14:16:55 +0300 Message-Id: <20180214111656.88514-9-kirill.shutemov@linux.intel.com> In-Reply-To: <20180214111656.88514-1-kirill.shutemov@linux.intel.com> References: <20180214111656.88514-1-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Ingo Molnar , x86@kernel.org, Thomas Gleixner , "H. Peter Anvin" Cc: Linus Torvalds , Andy Lutomirski , Borislav Petkov , Andi Kleen , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" For boot-time switching between paging modes, we need to be able to adjust virtual mask shifts. The change doesn't affect the kernel image size much: text data bss dec hex filename 8628892 4734340 1368064 14731296 e0c820 vmlinux.before 8628966 4734340 1368064 14731370 e0c86a vmlinux.after Signed-off-by: Kirill A. Shutemov --- arch/x86/entry/entry_64.S | 12 ++++++++++++ arch/x86/include/asm/page_64_types.h | 2 +- arch/x86/mm/dump_pagetables.c | 12 ++++++++++-- arch/x86/mm/kaslr.c | 4 +++- 4 files changed, 26 insertions(+), 4 deletions(-) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index cd216c9431e1..1608b13a0b36 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -260,8 +260,20 @@ GLOBAL(entry_SYSCALL_64_after_hwframe) * Change top bits to match most significant bit (47th or 56th bit * depending on paging mode) in the address. */ +#ifdef CONFIG_X86_5LEVEL + testl $1, pgtable_l5_enabled(%rip) + jz 1f + shl $(64 - 57), %rcx + sar $(64 - 57), %rcx + jmp 2f +1: + shl $(64 - 48), %rcx + sar $(64 - 48), %rcx +2: +#else shl $(64 - (__VIRTUAL_MASK_SHIFT+1)), %rcx sar $(64 - (__VIRTUAL_MASK_SHIFT+1)), %rcx +#endif /* If this changed %rcx, it was not canonical */ cmpq %rcx, %r11 diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h index d54a3d5b5b3b..fa7dc7cd8c19 100644 --- a/arch/x86/include/asm/page_64_types.h +++ b/arch/x86/include/asm/page_64_types.h @@ -56,7 +56,7 @@ #define __PHYSICAL_MASK_SHIFT 52 #ifdef CONFIG_X86_5LEVEL -#define __VIRTUAL_MASK_SHIFT 56 +#define __VIRTUAL_MASK_SHIFT (pgtable_l5_enabled ? 56 : 47) #else #define __VIRTUAL_MASK_SHIFT 47 #endif diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c index 420058b05d39..9efee6f464ab 100644 --- a/arch/x86/mm/dump_pagetables.c +++ b/arch/x86/mm/dump_pagetables.c @@ -85,8 +85,12 @@ static struct addr_marker address_markers[] = { [VMALLOC_START_NR] = { 0UL, "vmalloc() Area" }, [VMEMMAP_START_NR] = { 0UL, "Vmemmap" }, #ifdef CONFIG_KASAN - [KASAN_SHADOW_START_NR] = { KASAN_SHADOW_START, "KASAN shadow" }, - [KASAN_SHADOW_END_NR] = { KASAN_SHADOW_END, "KASAN shadow end" }, + /* + * These fields get initialized with the (dynamic) + * KASAN_SHADOW_{START,END} values in pt_dump_init(). + */ + [KASAN_SHADOW_START_NR] = { 0UL, "KASAN shadow" }, + [KASAN_SHADOW_END_NR] = { 0UL, "KASAN shadow end" }, #endif #ifdef CONFIG_MODIFY_LDT_SYSCALL [LDT_NR] = { 0UL, "LDT remap" }, @@ -571,6 +575,10 @@ static int __init pt_dump_init(void) #ifdef CONFIG_MODIFY_LDT_SYSCALL address_markers[LDT_NR].start_address = LDT_BASE_ADDR; #endif +#ifdef CONFIG_KASAN + address_markers[KASAN_SHADOW_START_NR].start_address = KASAN_SHADOW_START; + address_markers[KASAN_SHADOW_END_NR].start_address = KASAN_SHADOW_END; +#endif #endif #ifdef CONFIG_X86_32 address_markers[VMALLOC_START_NR].start_address = VMALLOC_START; diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index 515b98a8ccee..d079878c6cbc 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -52,7 +52,7 @@ static __initdata struct kaslr_memory_region { unsigned long *base; unsigned long size_tb; } kaslr_regions[] = { - { &page_offset_base, 1 << (__PHYSICAL_MASK_SHIFT - TB_SHIFT) /* Maximum */ }, + { &page_offset_base, 0 }, { &vmalloc_base, VMALLOC_SIZE_TB }, { &vmemmap_base, 1 }, }; @@ -93,6 +93,8 @@ void __init kernel_randomize_memory(void) if (!kaslr_memory_enabled()) return; + kaslr_regions[0].size_tb = 1 << (__PHYSICAL_MASK_SHIFT - TB_SHIFT); + /* * Update Physical memory mapping to available and * add padding if needed (especially for memory hotplug support). -- 2.15.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org