// SPDX-License-Identifier: GPL-2.0-only
#define pr_fmt(fmt) "SMP alternatives: " fmt
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/perf_event.h>
#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/stringify.h>
#include <linux/highmem.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/memory.h>
#include <linux/stop_machine.h>
#include <linux/slab.h>
#include <linux/kdebug.h>
#include <linux/kprobes.h>
#include <linux/mmu_context.h>
#include <linux/bsearch.h>
#include <linux/sync_core.h>
#include <asm/text-patching.h>
#include <asm/alternative.h>
#include <asm/sections.h>
#include <asm/mce.h>
#include <asm/nmi.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/insn.h>
#include <asm/io.h>
#include <asm/fixmap.h>
#include <asm/paravirt.h>
int __read_mostly alternatives_patched;
EXPORT_SYMBOL_GPL(alternatives_patched);
#define MAX_PATCH_LEN (255-1)
static int __initdata_or_module debug_alternative;
static int __init debug_alt(char *str)
{
debug_alternative = 1;
return 1;
}
__setup("debug-alternative", debug_alt);
static int noreplace_smp;
static int __init setup_noreplace_smp(char *str)
{
noreplace_smp = 1;
return 1;
}
__setup("noreplace-smp", setup_noreplace_smp);
#define DPRINTK(fmt, args...) \
do { \
if (debug_alternative) \
printk(KERN_DEBUG pr_fmt(fmt) "\n", ##args); \
} while (0)
#define DUMP_BYTES(buf, len, fmt, args...) \
do { \
if (unlikely(debug_alternative)) { \
int j; \
\
if (!(len)) \
break; \
\
printk(KERN_DEBUG pr_fmt(fmt), ##args); \
for (j = 0; j < (len) - 1; j++) \
printk(KERN_CONT "%02hhx ", buf[j]); \
printk(KERN_CONT "%02hhx\n", buf[j]); \
} \
} while (0)
const unsigned char x86nops[] =
{
BYTES_NOP1,
BYTES_NOP2,
BYTES_NOP3,
BYTES_NOP4,
BYTES_NOP5,
BYTES_NOP6,
BYTES_NOP7,
BYTES_NOP8,
};
const unsigned char * const x86_nops[ASM_NOP_MAX+1] =
{
NULL,
x86nops,
x86nops + 1,
x86nops + 1 + 2,
x86nops + 1 + 2 + 3,
x86nops + 1 + 2 + 3 + 4,
x86nops + 1 + 2 + 3 + 4 + 5,
x86nops + 1 + 2 + 3 + 4 + 5 + 6,
x86nops + 1 + 2 + 3 + 4 + 5 + 6 + 7,
};
/* Use this to add nops to a buffer, then text_poke the whole buffer. */
static void __init_or_module add_nops(void *insns, unsigned int len)
{
while (len > 0) {
unsigned int noplen = len;
if (noplen > ASM_NOP_MAX)
noplen = ASM_NOP_MAX;
memcpy(insns, x86_nops[noplen], noplen);
insns += noplen;
len -= noplen;
}
}
extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
extern s32 __smp_locks[], __smp_locks_end[];
void text_poke_early(void *addr, const void *opcode, size_t len);
/*
* Are we looking at a near JMP with a 1 or 4-byte displacement.
*/
static inline bool is_jmp(const u8 opcode