diff options
Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.9.21/0007-kaiser-stack-map-PAGE_SIZE-at-THREAD_SIZE-PAGE_SIZE.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.9.21/0007-kaiser-stack-map-PAGE_SIZE-at-THREAD_SIZE-PAGE_SIZE.patch | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.9.21/0007-kaiser-stack-map-PAGE_SIZE-at-THREAD_SIZE-PAGE_SIZE.patch b/common/recipes-kernel/linux/linux-yocto-4.9.21/0007-kaiser-stack-map-PAGE_SIZE-at-THREAD_SIZE-PAGE_SIZE.patch new file mode 100644 index 00000000..c34c59d8 --- /dev/null +++ b/common/recipes-kernel/linux/linux-yocto-4.9.21/0007-kaiser-stack-map-PAGE_SIZE-at-THREAD_SIZE-PAGE_SIZE.patch @@ -0,0 +1,145 @@ +From 4b7cba0c9e6cd74dd190b1d730d07f3c682cb1c9 Mon Sep 17 00:00:00 2001 +From: Hugh Dickins <hughd@google.com> +Date: Sun, 3 Sep 2017 18:57:03 -0700 +Subject: [PATCH 007/102] kaiser: stack map PAGE_SIZE at THREAD_SIZE-PAGE_SIZE + +Kaiser only needs to map one page of the stack; and +kernel/fork.c did not build on powerpc (no __PAGE_KERNEL). +It's all cleaner if linux/kaiser.h provides kaiser_map_thread_stack() +and kaiser_unmap_thread_stack() wrappers around asm/kaiser.h's +kaiser_add_mapping() and kaiser_remove_mapping(). And use +linux/kaiser.h in init/main.c to avoid the #ifdefs there. + +Signed-off-by: Hugh Dickins <hughd@google.com> +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +--- + include/linux/kaiser.h | 40 +++++++++++++++++++++++++++++++++------- + init/main.c | 6 +----- + kernel/fork.c | 7 ++----- + 3 files changed, 36 insertions(+), 17 deletions(-) + +diff --git a/include/linux/kaiser.h b/include/linux/kaiser.h +index 9db5433..4a4d6d9 100644 +--- a/include/linux/kaiser.h ++++ b/include/linux/kaiser.h +@@ -1,26 +1,52 @@ +-#ifndef _INCLUDE_KAISER_H +-#define _INCLUDE_KAISER_H ++#ifndef _LINUX_KAISER_H ++#define _LINUX_KAISER_H + + #ifdef CONFIG_KAISER + #include <asm/kaiser.h> ++ ++static inline int kaiser_map_thread_stack(void *stack) ++{ ++ /* ++ * Map that page of kernel stack on which we enter from user context. ++ */ ++ return kaiser_add_mapping((unsigned long)stack + ++ THREAD_SIZE - PAGE_SIZE, PAGE_SIZE, __PAGE_KERNEL); ++} ++ ++static inline void kaiser_unmap_thread_stack(void *stack) ++{ ++ /* ++ * Note: may be called even when kaiser_map_thread_stack() failed. ++ */ ++ kaiser_remove_mapping((unsigned long)stack + ++ THREAD_SIZE - PAGE_SIZE, PAGE_SIZE); ++} + #else + + /* + * These stubs are used whenever CONFIG_KAISER is off, which +- * includes architectures that support KAISER, but have it +- * disabled. ++ * includes architectures that support KAISER, but have it disabled. + */ + + static inline void kaiser_init(void) + { + } +-static inline void kaiser_remove_mapping(unsigned long start, unsigned long size) ++static inline int kaiser_add_mapping(unsigned long addr, ++ unsigned long size, unsigned long flags) ++{ ++ return 0; ++} ++static inline void kaiser_remove_mapping(unsigned long start, ++ unsigned long size) + { + } +-static inline int kaiser_add_mapping(unsigned long addr, unsigned long size, unsigned long flags) ++static inline int kaiser_map_thread_stack(void *stack) + { + return 0; + } ++static inline void kaiser_unmap_thread_stack(void *stack) ++{ ++} + + #endif /* !CONFIG_KAISER */ +-#endif /* _INCLUDE_KAISER_H */ ++#endif /* _LINUX_KAISER_H */ +diff --git a/init/main.c b/init/main.c +index d2c8c23..eb47369 100644 +--- a/init/main.c ++++ b/init/main.c +@@ -81,15 +81,13 @@ + #include <linux/integrity.h> + #include <linux/proc_ns.h> + #include <linux/io.h> ++#include <linux/kaiser.h> + + #include <asm/io.h> + #include <asm/bugs.h> + #include <asm/setup.h> + #include <asm/sections.h> + #include <asm/cacheflush.h> +-#ifdef CONFIG_KAISER +-#include <asm/kaiser.h> +-#endif + + static int kernel_init(void *); + +@@ -477,9 +475,7 @@ static void __init mm_init(void) + pgtable_init(); + vmalloc_init(); + ioremap_huge_init(); +-#ifdef CONFIG_KAISER + kaiser_init(); +-#endif + } + + asmlinkage __visible void __init start_kernel(void) +diff --git a/kernel/fork.c b/kernel/fork.c +index 8013f22..6b0e8bd 100644 +--- a/kernel/fork.c ++++ b/kernel/fork.c +@@ -212,12 +212,9 @@ static unsigned long *alloc_thread_stack_node(struct task_struct *tsk, int node) + #endif + } + +-extern void kaiser_remove_mapping(unsigned long start_addr, unsigned long size); + static inline void free_thread_stack(struct task_struct *tsk) + { +-#ifdef CONFIG_KAISER +- kaiser_remove_mapping((unsigned long)tsk->stack, THREAD_SIZE); +-#endif ++ kaiser_unmap_thread_stack(tsk->stack); + #ifdef CONFIG_VMAP_STACK + if (task_stack_vm_area(tsk)) { + unsigned long flags; +@@ -501,7 +498,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node) + */ + tsk->stack = stack; + +- err= kaiser_add_mapping((unsigned long)tsk->stack, THREAD_SIZE, __PAGE_KERNEL); ++ err= kaiser_map_thread_stack(tsk->stack); + if (err) + goto free_stack; + #ifdef CONFIG_VMAP_STACK +-- +2.7.4 + |