diff options
| author | Baoquan He <[email protected]> | 2018-10-06 16:43:25 +0800 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2018-10-06 14:46:46 +0200 |
| commit | 06d4a462e954756f3d3d54e6f3f1bdc2e6f592a9 (patch) | |
| tree | b51c46fa5a90bce676dc65af68b9ce5c269870da | |
| parent | 992b649a3f013465d8128da02e5449def662a4c3 (diff) | |
x86/KASLR: Update KERNEL_IMAGE_SIZE description
Currently CONFIG_RANDOMIZE_BASE=y is set by default, which makes some of the
old comments above the KERNEL_IMAGE_SIZE definition out of date. Update them
to the current state of affairs.
Signed-off-by: Baoquan He <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | arch/x86/include/asm/page_64_types.h | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h index 6afac386a434..cd0cf1c568b4 100644 --- a/arch/x86/include/asm/page_64_types.h +++ b/arch/x86/include/asm/page_64_types.h @@ -59,13 +59,16 @@ #endif /* - * Kernel image size is limited to 1GiB due to the fixmap living in the - * next 1GiB (see level2_kernel_pgt in arch/x86/kernel/head_64.S). Use - * 512MiB by default, leaving 1.5GiB for modules once the page tables - * are fully set up. If kernel ASLR is configured, it can extend the - * kernel page table mapping, reducing the size of the modules area. + * 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). + * + * On KASLR use 1 GiB by default, leaving 1 GiB for modules once the + * page tables are fully set up. + * + * If KASLR is disabled we can shrink it to 0.5 GiB and increase the size + * of the modules area to 1.5 GiB. */ -#if defined(CONFIG_RANDOMIZE_BASE) +#ifdef CONFIG_RANDOMIZE_BASE #define KERNEL_IMAGE_SIZE (1024 * 1024 * 1024) #else #define KERNEL_IMAGE_SIZE (512 * 1024 * 1024) |