mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-17 23:36:49 +07:00
7e6fc2f50a
The outb() function takes parameters value and port, in that order. Fix
the parameters used in the kalsr i8254 fallback code.
Fixes: 5bfce5ef55 ("x86, kaslr: Provide randomness functions")
Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: linux@endlessm.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190107034024.15005-1-drake@endlessm.com
93 lines
2.1 KiB
C
93 lines
2.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Entropy functions used on early boot for KASLR base and memory
|
|
* randomization. The base randomization is done in the compressed
|
|
* kernel and memory randomization is done early when the regular
|
|
* kernel starts. This file is included in the compressed kernel and
|
|
* normally linked in the regular.
|
|
*/
|
|
#include <asm/asm.h>
|
|
#include <asm/kaslr.h>
|
|
#include <asm/msr.h>
|
|
#include <asm/archrandom.h>
|
|
#include <asm/e820/api.h>
|
|
#include <asm/io.h>
|
|
|
|
/*
|
|
* When built for the regular kernel, several functions need to be stubbed out
|
|
* or changed to their regular kernel equivalent.
|
|
*/
|
|
#ifndef KASLR_COMPRESSED_BOOT
|
|
#include <asm/cpufeature.h>
|
|
#include <asm/setup.h>
|
|
|
|
#define debug_putstr(v) early_printk("%s", v)
|
|
#define has_cpuflag(f) boot_cpu_has(f)
|
|
#define get_boot_seed() kaslr_offset()
|
|
#endif
|
|
|
|
#define I8254_PORT_CONTROL 0x43
|
|
#define I8254_PORT_COUNTER0 0x40
|
|
#define I8254_CMD_READBACK 0xC0
|
|
#define I8254_SELECT_COUNTER0 0x02
|
|
#define I8254_STATUS_NOTREADY 0x40
|
|
static inline u16 i8254(void)
|
|
{
|
|
u16 status, timer;
|
|
|
|
do {
|
|
outb(I8254_CMD_READBACK | I8254_SELECT_COUNTER0,
|
|
I8254_PORT_CONTROL);
|
|
status = inb(I8254_PORT_COUNTER0);
|
|
timer = inb(I8254_PORT_COUNTER0);
|
|
timer |= inb(I8254_PORT_COUNTER0) << 8;
|
|
} while (status & I8254_STATUS_NOTREADY);
|
|
|
|
return timer;
|
|
}
|
|
|
|
unsigned long kaslr_get_random_long(const char *purpose)
|
|
{
|
|
#ifdef CONFIG_X86_64
|
|
const unsigned long mix_const = 0x5d6008cbf3848dd3UL;
|
|
#else
|
|
const unsigned long mix_const = 0x3f39e593UL;
|
|
#endif
|
|
unsigned long raw, random = get_boot_seed();
|
|
bool use_i8254 = true;
|
|
|
|
debug_putstr(purpose);
|
|
debug_putstr(" KASLR using");
|
|
|
|
if (has_cpuflag(X86_FEATURE_RDRAND)) {
|
|
debug_putstr(" RDRAND");
|
|
if (rdrand_long(&raw)) {
|
|
random ^= raw;
|
|
use_i8254 = false;
|
|
}
|
|
}
|
|
|
|
if (has_cpuflag(X86_FEATURE_TSC)) {
|
|
debug_putstr(" RDTSC");
|
|
raw = rdtsc();
|
|
|
|
random ^= raw;
|
|
use_i8254 = false;
|
|
}
|
|
|
|
if (use_i8254) {
|
|
debug_putstr(" i8254");
|
|
random ^= i8254();
|
|
}
|
|
|
|
/* Circular multiply for better bit diffusion */
|
|
asm(_ASM_MUL "%3"
|
|
: "=a" (random), "=d" (raw)
|
|
: "a" (random), "rm" (mix_const));
|
|
random += raw;
|
|
|
|
debug_putstr("...\n");
|
|
|
|
return random;
|
|
}
|