kernel_optimize_test/arch/x86/include/asm/setup.h
Borislav Petkov 78cac48c04 x86/mm/KASLR: Propagate KASLR status to kernel proper
Commit:

  e2b32e6785 ("x86, kaslr: randomize module base load address")

made module base address randomization unconditional and didn't regard
disabled KKASLR due to CONFIG_HIBERNATION and command line option
"nokaslr". For more info see (now reverted) commit:

  f47233c2d3 ("x86/mm/ASLR: Propagate base load address calculation")

In order to propagate KASLR status to kernel proper, we need a single bit
in boot_params.hdr.loadflags and we've chosen bit 1 thus leaving the
top-down allocated bits for bits supposed to be used by the bootloader.

Originally-From: Jiri Kosina <jkosina@suse.cz>
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-03 15:26:15 +02:00

132 lines
3.2 KiB
C

#ifndef _ASM_X86_SETUP_H
#define _ASM_X86_SETUP_H
#include <uapi/asm/setup.h>
#define COMMAND_LINE_SIZE 2048
#include <linux/linkage.h>
#ifdef __i386__
#include <linux/pfn.h>
/*
* Reserved space for vmalloc and iomap - defined in asm/page.h
*/
#define MAXMEM_PFN PFN_DOWN(MAXMEM)
#define MAX_NONPAE_PFN (1 << 20)
#endif /* __i386__ */
#define PARAM_SIZE 4096 /* sizeof(struct boot_params) */
#define OLD_CL_MAGIC 0xA33F
#define OLD_CL_ADDRESS 0x020 /* Relative to real mode data */
#define NEW_CL_POINTER 0x228 /* Relative to real mode data */
#ifndef __ASSEMBLY__
#include <asm/bootparam.h>
#include <asm/x86_init.h>
extern u64 relocated_ramdisk;
/* Interrupt control for vSMPowered x86_64 systems */
#ifdef CONFIG_X86_64
void vsmp_init(void);
#else
static inline void vsmp_init(void) { }
#endif
void setup_bios_corruption_check(void);
extern unsigned long saved_video_mode;
extern void reserve_standard_io_resources(void);
extern void i386_reserve_resources(void);
extern void setup_default_timer_irq(void);
#ifdef CONFIG_X86_INTEL_MID
extern void x86_intel_mid_early_setup(void);
#else
static inline void x86_intel_mid_early_setup(void) { }
#endif
#ifdef CONFIG_X86_INTEL_CE
extern void x86_ce4100_early_setup(void);
#else
static inline void x86_ce4100_early_setup(void) { }
#endif
#ifndef _SETUP
#include <asm/espfix.h>
/*
* This is set up by the setup-routine at boot-time
*/
extern struct boot_params boot_params;
static inline bool kaslr_enabled(void)
{
return !!(boot_params.hdr.loadflags & KASLR_FLAG);
}
/*
* Do NOT EVER look at the BIOS memory size location.
* It does not work on many machines.
*/
#define LOWMEMSIZE() (0x9f000)
/* exceedingly early brk-like allocator */
extern unsigned long _brk_end;
void *extend_brk(size_t size, size_t align);
/*
* Reserve space in the brk section. The name must be unique within
* the file, and somewhat descriptive. The size is in bytes. Must be
* used at file scope.
*
* (This uses a temp function to wrap the asm so we can pass it the
* size parameter; otherwise we wouldn't be able to. We can't use a
* "section" attribute on a normal variable because it always ends up
* being @progbits, which ends up allocating space in the vmlinux
* executable.)
*/
#define RESERVE_BRK(name,sz) \
static void __section(.discard.text) __used notrace \
__brk_reservation_fn_##name##__(void) { \
asm volatile ( \
".pushsection .brk_reservation,\"aw\",@nobits;" \
".brk." #name ":" \
" 1:.skip %c0;" \
" .size .brk." #name ", . - 1b;" \
" .popsection" \
: : "i" (sz)); \
}
/* Helper for reserving space for arrays of things */
#define RESERVE_BRK_ARRAY(type, name, entries) \
type *name; \
RESERVE_BRK(name, sizeof(type) * entries)
extern void probe_roms(void);
#ifdef __i386__
asmlinkage void __init i386_start_kernel(void);
#else
asmlinkage void __init x86_64_start_kernel(char *real_mode);
asmlinkage void __init x86_64_start_reservations(char *real_mode_data);
#endif /* __i386__ */
#endif /* _SETUP */
#else
#define RESERVE_BRK(name,sz) \
.pushsection .brk_reservation,"aw",@nobits; \
.brk.name: \
1: .skip sz; \
.size .brk.name,.-1b; \
.popsection
#endif /* __ASSEMBLY__ */
#endif /* _ASM_X86_SETUP_H */