From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f71.google.com (mail-ed1-f71.google.com [209.85.208.71]) by kanga.kvack.org (Postfix) with ESMTP id BEEFE6B02AB for ; Wed, 18 Jul 2018 05:41:41 -0400 (EDT) Received: by mail-ed1-f71.google.com with SMTP id f8-v6so1702954eds.6 for ; Wed, 18 Jul 2018 02:41:41 -0700 (PDT) Received: from theia.8bytes.org (8bytes.org. [2a01:238:4383:600:38bc:a715:4b6d:a889]) by mx.google.com with ESMTPS id p27-v6si3148874edi.276.2018.07.18.02.41.40 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 18 Jul 2018 02:41:40 -0700 (PDT) From: Joerg Roedel Subject: [PATCH 33/39] x86/ldt: Reserve address-space range on 32 bit for the LDT Date: Wed, 18 Jul 2018 11:41:10 +0200 Message-Id: <1531906876-13451-34-git-send-email-joro@8bytes.org> In-Reply-To: <1531906876-13451-1-git-send-email-joro@8bytes.org> References: <1531906876-13451-1-git-send-email-joro@8bytes.org> Sender: owner-linux-mm@kvack.org List-ID: To: Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Linus Torvalds , Andy Lutomirski , Dave Hansen , Josh Poimboeuf , Juergen Gross , Peter Zijlstra , Borislav Petkov , Jiri Kosina , Boris Ostrovsky , Brian Gerst , David Laight , Denys Vlasenko , Eduardo Valentin , Greg KH , Will Deacon , aliguori@amazon.com, daniel.gruss@iaik.tugraz.at, hughd@google.com, keescook@google.com, Andrea Arcangeli , Waiman Long , Pavel Machek , "David H . Gutteridge" , jroedel@suse.de, joro@8bytes.org From: Joerg Roedel Reserve 2MB/4MB of address-space for mapping the LDT to user-space on 32 bit PTI kernels. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/pgtable_32_types.h | 7 +++++-- arch/x86/mm/dump_pagetables.c | 9 +++++++++ 2 files changed, 14 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/pgtable_32_types.h b/arch/x86/include/asm/pgtable_32_types.h index d9a001a..7297810 100644 --- a/arch/x86/include/asm/pgtable_32_types.h +++ b/arch/x86/include/asm/pgtable_32_types.h @@ -50,13 +50,16 @@ extern bool __vmalloc_start_set; /* set once high_memory is set */ ((FIXADDR_TOT_START - PAGE_SIZE * (CPU_ENTRY_AREA_PAGES + 1)) \ & PMD_MASK) -#define PKMAP_BASE \ +#define LDT_BASE_ADDR \ ((CPU_ENTRY_AREA_BASE - PAGE_SIZE) & PMD_MASK) +#define PKMAP_BASE \ + ((LDT_BASE_ADDR - PAGE_SIZE) & PMD_MASK) + #ifdef CONFIG_HIGHMEM # define VMALLOC_END (PKMAP_BASE - 2 * PAGE_SIZE) #else -# define VMALLOC_END (CPU_ENTRY_AREA_BASE - 2 * PAGE_SIZE) +# define VMALLOC_END (LDT_BASE_ADDR - 2 * PAGE_SIZE) #endif #define MODULES_VADDR VMALLOC_START diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c index e6fd0cd..ccd92c4 100644 --- a/arch/x86/mm/dump_pagetables.c +++ b/arch/x86/mm/dump_pagetables.c @@ -123,6 +123,9 @@ enum address_markers_idx { #ifdef CONFIG_HIGHMEM PKMAP_BASE_NR, #endif +#ifdef CONFIG_MODIFY_LDT_SYSCALL + LDT_NR, +#endif CPU_ENTRY_AREA_NR, FIXADDR_START_NR, END_OF_SPACE_NR, @@ -136,6 +139,9 @@ static struct addr_marker address_markers[] = { #ifdef CONFIG_HIGHMEM [PKMAP_BASE_NR] = { 0UL, "Persistent kmap() Area" }, #endif +#ifdef CONFIG_MODIFY_LDT_SYSCALL + [LDT_NR] = { 0UL, "LDT remap" }, +#endif [CPU_ENTRY_AREA_NR] = { 0UL, "CPU entry area" }, [FIXADDR_START_NR] = { 0UL, "Fixmap area" }, [END_OF_SPACE_NR] = { -1, NULL } @@ -609,6 +615,9 @@ static int __init pt_dump_init(void) # endif address_markers[FIXADDR_START_NR].start_address = FIXADDR_START; address_markers[CPU_ENTRY_AREA_NR].start_address = CPU_ENTRY_AREA_BASE; +# ifdef CONFIG_MODIFY_LDT_SYSCALL + address_markers[LDT_NR].start_address = LDT_BASE_ADDR; +# endif #endif return 0; } -- 2.7.4