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From: Christoph Hellwig <hch@lst.de>
To: Linus Torvalds <torvalds@linux-foundation.org>,
	Al Viro <viro@zeniv.linux.org.uk>,
	Michael Ellerman <mpe@ellerman.id.au>,
	x86@kernel.org
Cc: Kees Cook <keescook@chromium.org>,
	linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Subject: [PATCH 06/10] x86: move PAGE_OFFSET, TASK_SIZE & friends to page_{32,64}_types.h
Date: Thu, 27 Aug 2020 17:00:26 +0200	[thread overview]
Message-ID: <20200827150030.282762-7-hch@lst.de> (raw)
In-Reply-To: <20200827150030.282762-1-hch@lst.de>

At least for 64-bit this moves them closer to some of the defines
they are based on, and it prepares for using the TASK_SIZE_MAX
definition from assembly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
---
 arch/x86/include/asm/page_32_types.h | 11 +++++++
 arch/x86/include/asm/page_64_types.h | 38 +++++++++++++++++++++
 arch/x86/include/asm/processor.h     | 49 ----------------------------
 3 files changed, 49 insertions(+), 49 deletions(-)

diff --git a/arch/x86/include/asm/page_32_types.h b/arch/x86/include/asm/page_32_types.h
index 565ad755c785e2..26236925fb2c36 100644
--- a/arch/x86/include/asm/page_32_types.h
+++ b/arch/x86/include/asm/page_32_types.h
@@ -41,6 +41,17 @@
 #define __VIRTUAL_MASK_SHIFT	32
 #endif	/* CONFIG_X86_PAE */
 
+/*
+ * User space process size: 3GB (default).
+ */
+#define IA32_PAGE_OFFSET	PAGE_OFFSET
+#define TASK_SIZE		PAGE_OFFSET
+#define TASK_SIZE_LOW		TASK_SIZE
+#define TASK_SIZE_MAX		TASK_SIZE
+#define DEFAULT_MAP_WINDOW	TASK_SIZE
+#define STACK_TOP		TASK_SIZE
+#define STACK_TOP_MAX		STACK_TOP
+
 /*
  * Kernel image size is limited to 512 MB (see in arch/x86/kernel/head_32.S)
  */
diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h
index 288b065955b729..996595c9897e0a 100644
--- a/arch/x86/include/asm/page_64_types.h
+++ b/arch/x86/include/asm/page_64_types.h
@@ -58,6 +58,44 @@
 #define __VIRTUAL_MASK_SHIFT	47
 #endif
 
+/*
+ * User space process size.  This is the first address outside the user range.
+ * There are a few constraints that determine this:
+ *
+ * On Intel CPUs, if a SYSCALL instruction is at the highest canonical
+ * address, then that syscall will enter the kernel with a
+ * non-canonical return address, and SYSRET will explode dangerously.
+ * We avoid this particular problem by preventing anything executable
+ * from being mapped at the maximum canonical address.
+ *
+ * On AMD CPUs in the Ryzen family, there's a nasty bug in which the
+ * CPUs malfunction if they execute code from the highest canonical page.
+ * They'll speculate right off the end of the canonical space, and
+ * bad things happen.  This is worked around in the same way as the
+ * Intel problem.
+ *
+ * With page table isolation enabled, we map the LDT in ... [stay tuned]
+ */
+#define TASK_SIZE_MAX	((1UL << __VIRTUAL_MASK_SHIFT) - PAGE_SIZE)
+
+#define DEFAULT_MAP_WINDOW	((1UL << 47) - PAGE_SIZE)
+
+/* This decides where the kernel will search for a free chunk of vm
+ * space during mmap's.
+ */
+#define IA32_PAGE_OFFSET	((current->personality & ADDR_LIMIT_3GB) ? \
+					0xc0000000 : 0xFFFFe000)
+
+#define TASK_SIZE_LOW		(test_thread_flag(TIF_ADDR32) ? \
+					IA32_PAGE_OFFSET : DEFAULT_MAP_WINDOW)
+#define TASK_SIZE		(test_thread_flag(TIF_ADDR32) ? \
+					IA32_PAGE_OFFSET : TASK_SIZE_MAX)
+#define TASK_SIZE_OF(child)	((test_tsk_thread_flag(child, TIF_ADDR32)) ? \
+					IA32_PAGE_OFFSET : TASK_SIZE_MAX)
+
+#define STACK_TOP		TASK_SIZE_LOW
+#define STACK_TOP_MAX		TASK_SIZE_MAX
+
 /*
  * Maximum kernel image size is limited to 1 GiB, due to the fixmap living
  * in the next 1 GiB (see level2_kernel_pgt in arch/x86/kernel/head_64.S).
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 97143d87994c24..1618eeb08361a9 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -782,17 +782,6 @@ static inline void spin_lock_prefetch(const void *x)
 })
 
 #ifdef CONFIG_X86_32
-/*
- * User space process size: 3GB (default).
- */
-#define IA32_PAGE_OFFSET	PAGE_OFFSET
-#define TASK_SIZE		PAGE_OFFSET
-#define TASK_SIZE_LOW		TASK_SIZE
-#define TASK_SIZE_MAX		TASK_SIZE
-#define DEFAULT_MAP_WINDOW	TASK_SIZE
-#define STACK_TOP		TASK_SIZE
-#define STACK_TOP_MAX		STACK_TOP
-
 #define INIT_THREAD  {							  \
 	.sp0			= TOP_OF_INIT_STACK,			  \
 	.sysenter_cs		= __KERNEL_CS,				  \
@@ -802,44 +791,6 @@ static inline void spin_lock_prefetch(const void *x)
 #define KSTK_ESP(task)		(task_pt_regs(task)->sp)
 
 #else
-/*
- * User space process size.  This is the first address outside the user range.
- * There are a few constraints that determine this:
- *
- * On Intel CPUs, if a SYSCALL instruction is at the highest canonical
- * address, then that syscall will enter the kernel with a
- * non-canonical return address, and SYSRET will explode dangerously.
- * We avoid this particular problem by preventing anything executable
- * from being mapped at the maximum canonical address.
- *
- * On AMD CPUs in the Ryzen family, there's a nasty bug in which the
- * CPUs malfunction if they execute code from the highest canonical page.
- * They'll speculate right off the end of the canonical space, and
- * bad things happen.  This is worked around in the same way as the
- * Intel problem.
- *
- * With page table isolation enabled, we map the LDT in ... [stay tuned]
- */
-#define TASK_SIZE_MAX	((1UL << __VIRTUAL_MASK_SHIFT) - PAGE_SIZE)
-
-#define DEFAULT_MAP_WINDOW	((1UL << 47) - PAGE_SIZE)
-
-/* This decides where the kernel will search for a free chunk of vm
- * space during mmap's.
- */
-#define IA32_PAGE_OFFSET	((current->personality & ADDR_LIMIT_3GB) ? \
-					0xc0000000 : 0xFFFFe000)
-
-#define TASK_SIZE_LOW		(test_thread_flag(TIF_ADDR32) ? \
-					IA32_PAGE_OFFSET : DEFAULT_MAP_WINDOW)
-#define TASK_SIZE		(test_thread_flag(TIF_ADDR32) ? \
-					IA32_PAGE_OFFSET : TASK_SIZE_MAX)
-#define TASK_SIZE_OF(child)	((test_tsk_thread_flag(child, TIF_ADDR32)) ? \
-					IA32_PAGE_OFFSET : TASK_SIZE_MAX)
-
-#define STACK_TOP		TASK_SIZE_LOW
-#define STACK_TOP_MAX		TASK_SIZE_MAX
-
 #define INIT_THREAD  {						\
 	.addr_limit		= KERNEL_DS,			\
 }
-- 
2.28.0


  parent reply	other threads:[~2020-08-27 15:09 UTC|newest]

Thread overview: 45+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-08-27 15:00 remove the last set_fs() in common code, and remove it for x86 and powerpc v2 Christoph Hellwig
2020-08-27 15:00 ` [PATCH 01/10] fs: don't allow kernel reads and writes without iter ops Christoph Hellwig
2020-08-27 15:58   ` David Laight
2020-08-29  9:23     ` 'Christoph Hellwig'
     [not found]   ` <20200901064849.GI4299@shao2-debian>
2020-09-01  7:08     ` [fs] ef30fb3c60: kernel write not supported for file /sys/kernel/softlockup_panic Christoph Hellwig
2020-08-27 15:00 ` [PATCH 02/10] fs: don't allow splice read/write without explicit ops Christoph Hellwig
2020-08-27 15:00 ` [PATCH 03/10] uaccess: add infrastructure for kernel builds with set_fs() Christoph Hellwig
2020-08-27 15:00 ` [PATCH 04/10] test_bitmap: skip user bitmap tests for !CONFIG_SET_FS Christoph Hellwig
2020-08-27 15:00 ` [PATCH 05/10] lkdtm: disable set_fs-based " Christoph Hellwig
2020-08-27 18:06   ` Linus Torvalds
2020-08-29  9:24     ` Christoph Hellwig
2020-09-01 18:52       ` Kees Cook
2020-09-01 18:57       ` Kees Cook
2020-09-02  8:09         ` Christoph Hellwig
2020-08-27 15:00 ` Christoph Hellwig [this message]
2020-08-27 15:00 ` [PATCH 07/10] x86: make TASK_SIZE_MAX usable from assembly code Christoph Hellwig
2020-08-27 15:00 ` [PATCH 08/10] x86: remove address space overrides using set_fs() Christoph Hellwig
2020-08-27 18:15   ` Linus Torvalds
2020-08-29  9:25     ` Christoph Hellwig
2020-08-27 15:00 ` [PATCH 09/10] powerpc: use non-set_fs based maccess routines Christoph Hellwig
2020-08-27 15:00 ` [PATCH 10/10] powerpc: remove address space overrides using set_fs() Christoph Hellwig
2020-09-02  6:15   ` Christophe Leroy
2020-09-02 12:36     ` Christoph Hellwig
2020-09-02 13:13       ` David Laight
2020-09-02 13:24         ` Christophe Leroy
2020-09-02 13:51           ` David Laight
2020-09-02 14:12             ` Christophe Leroy
2020-09-02 15:02               ` David Laight
2020-09-02 15:17       ` Christophe Leroy
2020-09-02 18:02         ` Linus Torvalds
2020-09-03  7:11           ` Christoph Hellwig
2020-09-03  7:27             ` Christophe Leroy
2020-09-03  8:55             ` Christophe Leroy
2020-09-03  7:20           ` Christophe Leroy
2020-08-27 15:31 ` remove the last set_fs() in common code, and remove it for x86 and powerpc v2 Christoph Hellwig
2020-09-01 17:13 ` Christophe Leroy
2020-09-01 17:25   ` Al Viro
2020-09-01 17:42     ` Matthew Wilcox
2020-09-01 18:39     ` Christophe Leroy
2020-09-01 19:01     ` Christophe Leroy
2020-09-02  8:10     ` Christoph Hellwig
2020-10-27  9:29 ` [PATCH 02/10] fs: don't allow splice read/write without explicit ops David Howells
2020-10-27  9:51 ` David Howells
2020-10-27  9:54   ` Christoph Hellwig
2020-10-27 10:38   ` David Howells

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