diff options
Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.9.21/0013-kaiser-tidied-up-asm-kaiser.h-somewhat.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.9.21/0013-kaiser-tidied-up-asm-kaiser.h-somewhat.patch | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.9.21/0013-kaiser-tidied-up-asm-kaiser.h-somewhat.patch b/common/recipes-kernel/linux/linux-yocto-4.9.21/0013-kaiser-tidied-up-asm-kaiser.h-somewhat.patch new file mode 100644 index 00000000..37eb1c7b --- /dev/null +++ b/common/recipes-kernel/linux/linux-yocto-4.9.21/0013-kaiser-tidied-up-asm-kaiser.h-somewhat.patch @@ -0,0 +1,107 @@ +From e1c87b1c70f8cb5678116e407be3f6164ee52b0f Mon Sep 17 00:00:00 2001 +From: Hugh Dickins <hughd@google.com> +Date: Sun, 3 Sep 2017 19:18:07 -0700 +Subject: [PATCH 013/102] kaiser: tidied up asm/kaiser.h somewhat + +Mainly deleting a surfeit of blank lines, and reflowing header comment. + +Signed-off-by: Hugh Dickins <hughd@google.com> +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +--- + arch/x86/include/asm/kaiser.h | 32 +++++++++++++------------------- + 1 file changed, 13 insertions(+), 19 deletions(-) + +diff --git a/arch/x86/include/asm/kaiser.h b/arch/x86/include/asm/kaiser.h +index 0703f48..7394ba9 100644 +--- a/arch/x86/include/asm/kaiser.h ++++ b/arch/x86/include/asm/kaiser.h +@@ -1,15 +1,17 @@ + #ifndef _ASM_X86_KAISER_H + #define _ASM_X86_KAISER_H +- +-/* This file includes the definitions for the KAISER feature. +- * KAISER is a counter measure against x86_64 side channel attacks on the kernel virtual memory. +- * It has a shodow-pgd for every process. the shadow-pgd has a minimalistic kernel-set mapped, +- * but includes the whole user memory. Within a kernel context switch, or when an interrupt is handled, +- * the pgd is switched to the normal one. When the system switches to user mode, the shadow pgd is enabled. +- * By this, the virtual memory chaches are freed, and the user may not attack the whole kernel memory. ++/* ++ * This file includes the definitions for the KAISER feature. ++ * KAISER is a counter measure against x86_64 side channel attacks on ++ * the kernel virtual memory. It has a shadow pgd for every process: the ++ * shadow pgd has a minimalistic kernel-set mapped, but includes the whole ++ * user memory. Within a kernel context switch, or when an interrupt is handled, ++ * the pgd is switched to the normal one. When the system switches to user mode, ++ * the shadow pgd is enabled. By this, the virtual memory caches are freed, ++ * and the user may not attack the whole kernel memory. + * +- * A minimalistic kernel mapping holds the parts needed to be mapped in user mode, as the entry/exit functions +- * of the user space, or the stacks. ++ * A minimalistic kernel mapping holds the parts needed to be mapped in user ++ * mode, such as the entry/exit functions of the user space, or the stacks. + */ + #ifdef __ASSEMBLY__ + #ifdef CONFIG_KAISER +@@ -48,13 +50,10 @@ _SWITCH_TO_KERNEL_CR3 %rax + movq PER_CPU_VAR(unsafe_stack_register_backup), %rax + .endm + +- + .macro SWITCH_USER_CR3_NO_STACK +- + movq %rax, PER_CPU_VAR(unsafe_stack_register_backup) + _SWITCH_TO_USER_CR3 %rax + movq PER_CPU_VAR(unsafe_stack_register_backup), %rax +- + .endm + + #else /* CONFIG_KAISER */ +@@ -72,7 +71,6 @@ movq PER_CPU_VAR(unsafe_stack_register_backup), %rax + + #else /* __ASSEMBLY__ */ + +- + #ifdef CONFIG_KAISER + /* + * Upon kernel/user mode switch, it may happen that the address +@@ -80,7 +78,6 @@ movq PER_CPU_VAR(unsafe_stack_register_backup), %rax + * stored. To change the address space, another register is + * needed. A register therefore has to be stored/restored. + */ +- + DECLARE_PER_CPU_USER_MAPPED(unsigned long, unsafe_stack_register_backup); + + /** +@@ -95,7 +92,6 @@ DECLARE_PER_CPU_USER_MAPPED(unsigned long, unsafe_stack_register_backup); + */ + extern int kaiser_add_mapping(unsigned long addr, unsigned long size, unsigned long flags); + +- + /** + * kaiser_remove_mapping - unmap a virtual memory part of the shadow mapping + * @addr: the start address of the range +@@ -104,12 +100,12 @@ extern int kaiser_add_mapping(unsigned long addr, unsigned long size, unsigned l + extern void kaiser_remove_mapping(unsigned long start, unsigned long size); + + /** +- * kaiser_initialize_mapping - Initalize the shadow mapping ++ * kaiser_init - Initialize the shadow mapping + * + * Most parts of the shadow mapping can be mapped upon boot + * time. Only per-process things like the thread stacks + * or a new LDT have to be mapped at runtime. These boot- +- * time mappings are permanent and nevertunmapped. ++ * time mappings are permanent and never unmapped. + */ + extern void kaiser_init(void); + +@@ -117,6 +113,4 @@ extern void kaiser_init(void); + + #endif /* __ASSEMBLY */ + +- +- + #endif /* _ASM_X86_KAISER_H */ +-- +2.7.4 + |