From: Ingo Molnar <mingo@kernel.org>
To: linux-kernel@vger.kernel.org
Cc: Dave Hansen <dave.hansen@linux.intel.com>,
Andy Lutomirski <luto@amacapital.net>,
Thomas Gleixner <tglx@linutronix.de>,
"H . Peter Anvin" <hpa@zytor.com>,
Peter Zijlstra <peterz@infradead.org>,
Borislav Petkov <bp@alien8.de>,
Linus Torvalds <torvalds@linux-foundation.org>
Subject: [PATCH 24/43] x86/mm/kaiser: Mark per-cpu data structures required for entry/exit
Date: Fri, 24 Nov 2017 10:14:29 +0100 [thread overview]
Message-ID: <20171124091448.7649-25-mingo@kernel.org> (raw)
In-Reply-To: <20171124091448.7649-1-mingo@kernel.org>
From: Dave Hansen <dave.hansen@linux.intel.com>
These patches are based on work from a team at Graz University of
Technology posted here: https://github.com/IAIK/KAISER
The KAISER approach keeps two copies of the page tables: one for running
in the kernel and one for running userspace. But, there are a few
structures that are needed for switching in and out of the kernel and
a good subset of *those* are per-cpu data.
Here's a short summary of the things mapped to userspace:
* The gdt_page's virtual address is pointed to by the LGDT instruction.
It is needed to define the segments. Deeply required by CPU to run.
* cpu_tss tells the CPU, among other things, where the new stacks are
after user<->kernel transitions. Needed by the CPU to make ring
transitions.
* exception_stacks are needed at interrupt and exception entry
so that there is storage for, among other things, some temporary
space to permit clobbering a register to load the kernel CR3.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Daniel Gruss <daniel.gruss@iaik.tugraz.at>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Schwarz <michael.schwarz@iaik.tugraz.at>
Cc: Moritz Lipp <moritz.lipp@iaik.tugraz.at>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Fellner <richard.fellner@student.tugraz.at>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20171123003445.DF9EA351@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/include/asm/desc.h | 2 +-
arch/x86/include/asm/processor.h | 2 +-
arch/x86/kernel/cpu/common.c | 4 ++--
arch/x86/kernel/process.c | 2 +-
4 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h
index aab4fe9f49f8..300090d1c209 100644
--- a/arch/x86/include/asm/desc.h
+++ b/arch/x86/include/asm/desc.h
@@ -46,7 +46,7 @@ struct gdt_page {
struct desc_struct gdt[GDT_ENTRIES];
} __attribute__((aligned(PAGE_SIZE)));
-DECLARE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page);
+DECLARE_PER_CPU_PAGE_ALIGNED_USER_MAPPED(struct gdt_page, gdt_page);
/* Provide the original GDT */
static inline struct desc_struct *get_cpu_gdt_rw(unsigned int cpu)
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 54f3ee3bc8a0..83dd7c97ba5d 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -359,7 +359,7 @@ struct tss_struct {
unsigned long io_bitmap[IO_BITMAP_LONGS + 1];
} __aligned(PAGE_SIZE);
-DECLARE_PER_CPU_PAGE_ALIGNED(struct tss_struct, cpu_tss);
+DECLARE_PER_CPU_PAGE_ALIGNED_USER_MAPPED(struct tss_struct, cpu_tss);
/*
* sizeof(unsigned long) coming from an extra "long" at the end
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index f9c7e6852874..3b6920c9fef7 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -98,7 +98,7 @@ static const struct cpu_dev default_cpu = {
static const struct cpu_dev *this_cpu = &default_cpu;
-DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
+DEFINE_PER_CPU_PAGE_ALIGNED_USER_MAPPED(struct gdt_page, gdt_page) = { .gdt = {
#ifdef CONFIG_X86_64
/*
* We need valid kernel segments for data and code in long mode too
@@ -515,7 +515,7 @@ static const unsigned int exception_stack_sizes[N_EXCEPTION_STACKS] = {
[DEBUG_STACK - 1] = DEBUG_STKSZ
};
-static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
+DEFINE_PER_CPU_PAGE_ALIGNED_USER_MAPPED(char, exception_stacks
[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ]);
#endif
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 6a04287f222b..9365b4f965e0 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -47,7 +47,7 @@
* section. Since TSS's are completely CPU-local, we want them
* on exact cacheline boundaries, to eliminate cacheline ping-pong.
*/
-__visible DEFINE_PER_CPU_SHARED_ALIGNED(struct tss_struct, cpu_tss) = {
+__visible DEFINE_PER_CPU_SHARED_ALIGNED_USER_MAPPED(struct tss_struct, cpu_tss) = {
.x86_tss = {
/*
* .sp0 is only used when entering ring 0 from a lower
--
2.14.1
next prev parent reply other threads:[~2017-11-24 9:20 UTC|newest]
Thread overview: 81+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-24 9:14 [PATCH 00/43] x86 entry-stack and Kaiser series, 2017/11/24 version Ingo Molnar
2017-11-24 9:14 ` [PATCH 01/43] x86/decoder: Add new TEST instruction pattern Ingo Molnar
2017-11-24 10:38 ` Borislav Petkov
2017-12-02 7:39 ` Robert Elliott (Persistent Memory)
2017-11-24 9:14 ` [PATCH 02/43] x86/entry/64: Allocate and enable the SYSENTER stack Ingo Molnar
2017-11-24 9:14 ` [PATCH 03/43] x86/dumpstack: Add get_stack_info() support for " Ingo Molnar
2017-11-24 9:14 ` [PATCH 04/43] x86/gdt: Put per-cpu GDT remaps in ascending order Ingo Molnar
2017-11-24 9:14 ` [PATCH 05/43] x86/fixmap: Generalize the GDT fixmap mechanism Ingo Molnar
2017-11-24 11:00 ` Borislav Petkov
2017-11-24 9:14 ` [PATCH 06/43] x86/kasan/64: Teach KASAN about the cpu_entry_area Ingo Molnar
2017-11-24 9:14 ` [PATCH 07/43] x86/entry: Fix assumptions that the HW TSS is at the beginning of cpu_tss Ingo Molnar
2017-11-24 9:14 ` [PATCH 08/43] x86/dumpstack: Handle stack overflow on all stacks Ingo Molnar
2017-11-24 9:14 ` [PATCH 09/43] x86/entry: Move SYSENTER_stack to the beginning of struct tss_struct Ingo Molnar
2017-11-24 11:44 ` Borislav Petkov
2017-11-24 9:14 ` [PATCH 10/43] x86/entry: Remap the TSS into the cpu entry area Ingo Molnar
2017-11-24 9:14 ` [PATCH 11/43] x86/entry/64: Separate cpu_current_top_of_stack from TSS.sp0 Ingo Molnar
2017-11-24 14:19 ` Borislav Petkov
2017-11-24 9:14 ` [PATCH 12/43] x86/espfix/64: Stop assuming that pt_regs is on the entry stack Ingo Molnar
2017-11-24 9:14 ` [PATCH 13/43] x86/entry/64: Use a percpu trampoline stack for IDT entries Ingo Molnar
2017-11-24 11:27 ` Thomas Gleixner
2017-11-24 9:14 ` [PATCH 14/43] x86/entry/64: Return to userspace from the trampoline stack Ingo Molnar
2017-11-24 13:46 ` Thomas Gleixner
2017-11-24 9:14 ` [PATCH 15/43] x86/entry/64: Create a percpu SYSCALL entry trampoline Ingo Molnar
2017-11-24 13:52 ` Thomas Gleixner
2017-11-24 9:14 ` [PATCH 16/43] x86/irq: Remove an old outdated comment about context tracking races Ingo Molnar
2017-11-24 13:53 ` Thomas Gleixner
2017-11-24 9:14 ` [PATCH 17/43] x86/irq/64: Print the offending IP in the stack overflow warning Ingo Molnar
2017-11-24 14:22 ` Thomas Gleixner
2017-11-24 9:14 ` [PATCH 18/43] x86/entry/64: Move the IST stacks into cpu_entry_area Ingo Molnar
2017-11-24 14:23 ` Thomas Gleixner
2017-11-24 9:14 ` [PATCH 19/43] x86/entry/64: Remove the SYSENTER stack canary Ingo Molnar
2017-11-24 14:23 ` Thomas Gleixner
2017-11-24 9:14 ` [PATCH 20/43] x86/entry: Clean up SYSENTER_stack code Ingo Molnar
2017-11-24 14:24 ` Thomas Gleixner
2017-11-24 9:14 ` [PATCH 21/43] x86/mm/kaiser: Disable global pages by default with KAISER Ingo Molnar
2017-11-24 9:14 ` [PATCH 22/43] x86/mm/kaiser: Prepare assembly for entry/exit CR3 switching Ingo Molnar
2017-11-24 12:05 ` Peter Zijlstra
2017-11-24 12:17 ` Ingo Molnar
2017-11-24 12:45 ` Peter Zijlstra
2017-11-24 13:04 ` Thomas Gleixner
2017-11-24 9:14 ` [PATCH 23/43] x86/mm/kaiser: Introduce user-mapped per-cpu areas Ingo Molnar
2017-11-24 9:14 ` Ingo Molnar [this message]
2017-11-24 9:14 ` [PATCH 25/43] x86/mm/kaiser: Unmap kernel from userspace page tables (core patch) Ingo Molnar
2017-11-24 12:13 ` Peter Zijlstra
2017-11-24 13:46 ` Ingo Molnar
2017-11-24 12:16 ` Peter Zijlstra
2017-11-24 16:33 ` Dave Hansen
2017-11-26 15:13 ` Ingo Molnar
2017-11-24 13:30 ` Peter Zijlstra
2017-11-26 15:15 ` Ingo Molnar
2017-11-27 8:59 ` [PATCH] x86/mm/kaiser: Use the other page_table_lock pattern Peter Zijlstra
2017-11-27 8:59 ` [PATCH] mm: Unify page_table_lock allocation pattern Peter Zijlstra
2017-11-24 9:14 ` [PATCH 26/43] x86/mm/kaiser: Allow NX poison to be set in p4d/pgd Ingo Molnar
2017-11-24 9:14 ` [PATCH 27/43] x86/mm/kaiser: Make sure static PGDs are 8k in size Ingo Molnar
2017-11-24 9:14 ` [PATCH 28/43] x86/mm/kaiser: Map CPU entry area Ingo Molnar
2017-11-24 13:43 ` Peter Zijlstra
2017-11-24 9:14 ` [PATCH 29/43] x86/mm/kaiser: Map dynamically-allocated LDTs Ingo Molnar
2017-11-24 9:14 ` [PATCH 30/43] x86/mm/kaiser: Map espfix structures Ingo Molnar
2017-11-24 13:47 ` Peter Zijlstra
2017-11-24 16:17 ` Andy Lutomirski
2017-11-27 9:14 ` Peter Zijlstra
2017-11-27 15:35 ` Peter Zijlstra
2017-11-24 9:14 ` [PATCH 31/43] x86/mm/kaiser: Map entry stack variable Ingo Molnar
2017-11-24 9:14 ` [PATCH 32/43] x86/mm/kaiser: Map virtually-addressed performance monitoring buffers Ingo Molnar
2017-11-24 9:14 ` [PATCH 33/43] x86/mm: Move CR3 construction functions Ingo Molnar
2017-11-24 9:14 ` [PATCH 34/43] x86/mm: Remove hard-coded ASID limit checks Ingo Molnar
2017-11-24 9:14 ` [PATCH 35/43] x86/mm: Put mmu-to-h/w ASID translation in one place Ingo Molnar
2017-11-24 9:14 ` [PATCH 36/43] x86/mm: Allow flushing for future ASID switches Ingo Molnar
2017-11-24 9:14 ` [PATCH 37/43] x86/mm/kaiser: Use PCID feature to make user and kernel switches faster Ingo Molnar
2017-11-24 9:14 ` [PATCH 38/43] x86/mm/kaiser: Disable native VSYSCALL Ingo Molnar
2017-11-24 9:14 ` [PATCH 39/43] x86/mm/kaiser: Add debugfs file to turn KAISER on/off at runtime Ingo Molnar
2017-11-24 9:14 ` [PATCH 40/43] x86/mm/kaiser: Add a function to check for KAISER being enabled Ingo Molnar
2017-11-24 9:14 ` [PATCH 41/43] x86/mm/kaiser: Un-poison PGDs at runtime Ingo Molnar
2017-11-24 9:14 ` [PATCH 42/43] x86/mm/kaiser: Allow KAISER to be enabled/disabled " Ingo Molnar
2017-11-24 9:14 ` [PATCH 43/43] x86/mm/kaiser: Add Kconfig Ingo Molnar
2017-11-24 13:55 ` [PATCH 00/43] x86 entry-stack and Kaiser series, 2017/11/24 version Ingo Molnar
2017-11-24 15:23 ` Thomas Gleixner
2017-11-24 17:19 ` Ingo Molnar
2017-11-24 17:23 [PATCH 00/43] x86 entry-stack and Kaiser series, 2017/11/24, v2 version Ingo Molnar
2017-11-24 17:23 ` [PATCH 24/43] x86/mm/kaiser: Mark per-cpu data structures required for entry/exit Ingo Molnar
2017-11-25 17:17 ` Thomas Gleixner
2017-11-26 15:54 ` Ingo Molnar
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