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authorJason Gunthorpe <jgg@mellanox.com>2018-01-29 23:26:40 +0300
committerJason Gunthorpe <jgg@mellanox.com>2018-01-30 19:30:00 +0300
commite7996a9a77fc669387da43ff4823b91cc4872bd0 (patch)
tree617f0a128e222539d67e8cccc359f1bc4b984900 /arch/x86/mm/kaslr.c
parentb5fa635aab8f0d39a824c01991266a6d06f007fb (diff)
parentd8a5b80568a9cb66810e75b182018e9edb68e8ff (diff)
downloadlinux-e7996a9a77fc669387da43ff4823b91cc4872bd0.tar.xz
Merge tag v4.15 of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
To resolve conflicts in: drivers/infiniband/hw/mlx5/main.c drivers/infiniband/hw/mlx5/qp.c From patches merged into the -rc cycle. The conflict resolution matches what linux-next has been carrying. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'arch/x86/mm/kaslr.c')
-rw-r--r--arch/x86/mm/kaslr.c32
1 files changed, 9 insertions, 23 deletions
diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
index 879ef930e2c2..aedebd2ebf1e 100644
--- a/arch/x86/mm/kaslr.c
+++ b/arch/x86/mm/kaslr.c
@@ -34,25 +34,14 @@
#define TB_SHIFT 40
/*
- * Virtual address start and end range for randomization. The end changes base
- * on configuration to have the highest amount of space for randomization.
- * It increases the possible random position for each randomized region.
+ * Virtual address start and end range for randomization.
*
- * You need to add an if/def entry if you introduce a new memory region
- * compatible with KASLR. Your entry must be in logical order with memory
- * layout. For example, ESPFIX is before EFI because its virtual address is
- * before. You also need to add a BUILD_BUG_ON() in kernel_randomize_memory() to
- * ensure that this order is correct and won't be changed.
+ * The end address could depend on more configuration options to make the
+ * highest amount of space for randomization available, but that's too hard
+ * to keep straight and caused issues already.
*/
static const unsigned long vaddr_start = __PAGE_OFFSET_BASE;
-
-#if defined(CONFIG_X86_ESPFIX64)
-static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
-#elif defined(CONFIG_EFI)
-static const unsigned long vaddr_end = EFI_VA_END;
-#else
-static const unsigned long vaddr_end = __START_KERNEL_map;
-#endif
+static const unsigned long vaddr_end = CPU_ENTRY_AREA_BASE;
/* Default values */
unsigned long page_offset_base = __PAGE_OFFSET_BASE;
@@ -101,15 +90,12 @@ void __init kernel_randomize_memory(void)
unsigned long remain_entropy;
/*
- * All these BUILD_BUG_ON checks ensures the memory layout is
- * consistent with the vaddr_start/vaddr_end variables.
+ * These BUILD_BUG_ON checks ensure the memory layout is consistent
+ * with the vaddr_start/vaddr_end variables. These checks are very
+ * limited....
*/
BUILD_BUG_ON(vaddr_start >= vaddr_end);
- BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
- vaddr_end >= EFI_VA_END);
- BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
- IS_ENABLED(CONFIG_EFI)) &&
- vaddr_end >= __START_KERNEL_map);
+ BUILD_BUG_ON(vaddr_end != CPU_ENTRY_AREA_BASE);
BUILD_BUG_ON(vaddr_end > __START_KERNEL_map);
if (!kaslr_memory_enabled())