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Merge branch 'x86/cpu' into WIP.x86/core, to merge the NOP changes & resolve a semantic conflict 

Conflict-merge this main commit in essence:

  a89dfde3dc3c: ("x86: Remove dynamic NOP selection")

With this upstream commit:

  b90829704780: ("bpf: Use NOP_ATOMIC5 instead of emit_nops(&prog, 5) for BPF_TRAMP_F_CALL_ORIG")

Semantic merge conflict:

  arch/x86/net/bpf_jit_comp.c

  - memcpy(prog, ideal_nops[NOP_ATOMIC5], X86_PATCH_SIZE);
  + memcpy(prog, x86_nops[5], X86_PATCH_SIZE);

Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ingo Molnar 2021-04-02 12:34:19 +02:00
parent e855e80d00 a331f5fdd3
commit b1f480bc06
17 changed files with 192 additions and 360 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/include/asm/cpufeatures.h
View File

@ -84,7 +84,7 @@
/* CPU types for specific tunings: */
#define X86_FEATURE_K8 ( 3*32+ 4) /* "" Opteron, Athlon64 */
#define X86_FEATURE_K7 ( 3*32+ 5) /* "" Athlon */
/* FREE, was #define X86_FEATURE_K7 ( 3*32+ 5) "" Athlon */
#define X86_FEATURE_P3 ( 3*32+ 6) /* "" P3 */
#define X86_FEATURE_P4 ( 3*32+ 7) /* "" P4 */
#define X86_FEATURE_CONSTANT_TSC ( 3*32+ 8) /* TSC ticks at a constant rate */

12
arch/x86/include/asm/jump_label.h
View File

@ -6,12 +6,6 @@
#define JUMP_LABEL_NOP_SIZE 5
#ifdef CONFIG_X86_64
# define STATIC_KEY_INIT_NOP P6_NOP5_ATOMIC
#else
# define STATIC_KEY_INIT_NOP GENERIC_NOP5_ATOMIC
#endif
#include <asm/asm.h>
#include <asm/nops.h>
@ -23,7 +17,7 @@
static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
{
asm_volatile_goto("1:"
".byte " __stringify(STATIC_KEY_INIT_NOP) "\n\t"
".byte " __stringify(BYTES_NOP5) "\n\t"
".pushsection __jump_table, \"aw\" \n\t"
_ASM_ALIGN "\n\t"
".long 1b - ., %l[l_yes] - . \n\t"
@ -63,7 +57,7 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool
.long \target - .Lstatic_jump_after_\@
.Lstatic_jump_after_\@:
.else
.byte STATIC_KEY_INIT_NOP
.byte BYTES_NOP5
.endif
.pushsection __jump_table, "aw"
_ASM_ALIGN
@ -75,7 +69,7 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool
.macro STATIC_JUMP_IF_FALSE target, key, def
.Lstatic_jump_\@:
.if \def
.byte STATIC_KEY_INIT_NOP
.byte BYTES_NOP5
.else
/* Equivalent to "jmp.d32 \target" */
.byte 0xe9

176
arch/x86/include/asm/nops.h
View File

@ -4,89 +4,58 @@
/*
* Define nops for use with alternative() and for tracing.
*
* *_NOP5_ATOMIC must be a single instruction.
*/
#define NOP_DS_PREFIX 0x3e
#ifndef CONFIG_64BIT
/* generic versions from gas
1: nop
the following instructions are NOT nops in 64-bit mode,
for 64-bit mode use K8 or P6 nops instead
2: movl %esi,%esi
3: leal 0x00(%esi),%esi
4: leal 0x00(,%esi,1),%esi
6: leal 0x00000000(%esi),%esi
7: leal 0x00000000(,%esi,1),%esi
*/
#define GENERIC_NOP1 0x90
#define GENERIC_NOP2 0x89,0xf6
#define GENERIC_NOP3 0x8d,0x76,0x00
#define GENERIC_NOP4 0x8d,0x74,0x26,0x00
#define GENERIC_NOP5 GENERIC_NOP1,GENERIC_NOP4
#define GENERIC_NOP6 0x8d,0xb6,0x00,0x00,0x00,0x00
#define GENERIC_NOP7 0x8d,0xb4,0x26,0x00,0x00,0x00,0x00
#define GENERIC_NOP8 GENERIC_NOP1,GENERIC_NOP7
#define GENERIC_NOP5_ATOMIC NOP_DS_PREFIX,GENERIC_NOP4
/*
* Generic 32bit nops from GAS:
*
* 1: nop
* 2: movl %esi,%esi
* 3: leal 0x0(%esi),%esi
* 4: leal 0x0(%esi,%eiz,1),%esi
* 5: leal %ds:0x0(%esi,%eiz,1),%esi
* 6: leal 0x0(%esi),%esi
* 7: leal 0x0(%esi,%eiz,1),%esi
* 8: leal %ds:0x0(%esi,%eiz,1),%esi
*
* Except 5 and 8, which are DS prefixed 4 and 7 resp, where GAS would emit 2
* nop instructions.
*/
#define BYTES_NOP1 0x90
#define BYTES_NOP2 0x89,0xf6
#define BYTES_NOP3 0x8d,0x76,0x00
#define BYTES_NOP4 0x8d,0x74,0x26,0x00
#define BYTES_NOP5 0x3e,BYTES_NOP4
#define BYTES_NOP6 0x8d,0xb6,0x00,0x00,0x00,0x00
#define BYTES_NOP7 0x8d,0xb4,0x26,0x00,0x00,0x00,0x00
#define BYTES_NOP8 0x3e,BYTES_NOP7
/* Opteron 64bit nops
1: nop
2: osp nop
3: osp osp nop
4: osp osp osp nop
*/
#define K8_NOP1 GENERIC_NOP1
#define K8_NOP2 0x66,K8_NOP1
#define K8_NOP3 0x66,K8_NOP2
#define K8_NOP4 0x66,K8_NOP3
#define K8_NOP5 K8_NOP3,K8_NOP2
#define K8_NOP6 K8_NOP3,K8_NOP3
#define K8_NOP7 K8_NOP4,K8_NOP3
#define K8_NOP8 K8_NOP4,K8_NOP4
#define K8_NOP5_ATOMIC 0x66,K8_NOP4
#else
/* K7 nops
uses eax dependencies (arbitrary choice)
1: nop
2: movl %eax,%eax
3: leal (,%eax,1),%eax
4: leal 0x00(,%eax,1),%eax
6: leal 0x00000000(%eax),%eax
7: leal 0x00000000(,%eax,1),%eax
*/
#define K7_NOP1 GENERIC_NOP1
#define K7_NOP2 0x8b,0xc0
#define K7_NOP3 0x8d,0x04,0x20
#define K7_NOP4 0x8d,0x44,0x20,0x00
#define K7_NOP5 K7_NOP4,K7_NOP1
#define K7_NOP6 0x8d,0x80,0,0,0,0
#define K7_NOP7 0x8D,0x04,0x05,0,0,0,0
#define K7_NOP8 K7_NOP7,K7_NOP1
#define K7_NOP5_ATOMIC NOP_DS_PREFIX,K7_NOP4
/*
* Generic 64bit nops from GAS:
*
* 1: nop
* 2: osp nop
* 3: nopl (%eax)
* 4: nopl 0x00(%eax)
* 5: nopl 0x00(%eax,%eax,1)
* 6: osp nopl 0x00(%eax,%eax,1)
* 7: nopl 0x00000000(%eax)
* 8: nopl 0x00000000(%eax,%eax,1)
*/
#define BYTES_NOP1 0x90
#define BYTES_NOP2 0x66,BYTES_NOP1
#define BYTES_NOP3 0x0f,0x1f,0x00
#define BYTES_NOP4 0x0f,0x1f,0x40,0x00
#define BYTES_NOP5 0x0f,0x1f,0x44,0x00,0x00
#define BYTES_NOP6 0x66,BYTES_NOP5
#define BYTES_NOP7 0x0f,0x1f,0x80,0x00,0x00,0x00,0x00
#define BYTES_NOP8 0x0f,0x1f,0x84,0x00,0x00,0x00,0x00,0x00
/* P6 nops
uses eax dependencies (Intel-recommended choice)
1: nop
2: osp nop
3: nopl (%eax)
4: nopl 0x00(%eax)
5: nopl 0x00(%eax,%eax,1)
6: osp nopl 0x00(%eax,%eax,1)
7: nopl 0x00000000(%eax)
8: nopl 0x00000000(%eax,%eax,1)
Note: All the above are assumed to be a single instruction.
There is kernel code that depends on this.
*/
#define P6_NOP1 GENERIC_NOP1
#define P6_NOP2 0x66,0x90
#define P6_NOP3 0x0f,0x1f,0x00
#define P6_NOP4 0x0f,0x1f,0x40,0
#define P6_NOP5 0x0f,0x1f,0x44,0x00,0
#define P6_NOP6 0x66,0x0f,0x1f,0x44,0x00,0
#define P6_NOP7 0x0f,0x1f,0x80,0,0,0,0
#define P6_NOP8 0x0f,0x1f,0x84,0x00,0,0,0,0
#define P6_NOP5_ATOMIC P6_NOP5
#endif /* CONFIG_64BIT */
#ifdef __ASSEMBLY__
#define _ASM_MK_NOP(x) .byte x
@ -94,54 +63,19 @@
#define _ASM_MK_NOP(x) ".byte " __stringify(x) "\n"
#endif
#if defined(CONFIG_MK7)
#define ASM_NOP1 _ASM_MK_NOP(K7_NOP1)
#define ASM_NOP2 _ASM_MK_NOP(K7_NOP2)
#define ASM_NOP3 _ASM_MK_NOP(K7_NOP3)
#define ASM_NOP4 _ASM_MK_NOP(K7_NOP4)
#define ASM_NOP5 _ASM_MK_NOP(K7_NOP5)
#define ASM_NOP6 _ASM_MK_NOP(K7_NOP6)
#define ASM_NOP7 _ASM_MK_NOP(K7_NOP7)
#define ASM_NOP8 _ASM_MK_NOP(K7_NOP8)
#define ASM_NOP5_ATOMIC _ASM_MK_NOP(K7_NOP5_ATOMIC)
#elif defined(CONFIG_X86_P6_NOP)
#define ASM_NOP1 _ASM_MK_NOP(P6_NOP1)
#define ASM_NOP2 _ASM_MK_NOP(P6_NOP2)
#define ASM_NOP3 _ASM_MK_NOP(P6_NOP3)
#define ASM_NOP4 _ASM_MK_NOP(P6_NOP4)
#define ASM_NOP5 _ASM_MK_NOP(P6_NOP5)
#define ASM_NOP6 _ASM_MK_NOP(P6_NOP6)
#define ASM_NOP7 _ASM_MK_NOP(P6_NOP7)
#define ASM_NOP8 _ASM_MK_NOP(P6_NOP8)
#define ASM_NOP5_ATOMIC _ASM_MK_NOP(P6_NOP5_ATOMIC)
#elif defined(CONFIG_X86_64)
#define ASM_NOP1 _ASM_MK_NOP(K8_NOP1)
#define ASM_NOP2 _ASM_MK_NOP(K8_NOP2)
#define ASM_NOP3 _ASM_MK_NOP(K8_NOP3)
#define ASM_NOP4 _ASM_MK_NOP(K8_NOP4)
#define ASM_NOP5 _ASM_MK_NOP(K8_NOP5)
#define ASM_NOP6 _ASM_MK_NOP(K8_NOP6)
#define ASM_NOP7 _ASM_MK_NOP(K8_NOP7)
#define ASM_NOP8 _ASM_MK_NOP(K8_NOP8)
#define ASM_NOP5_ATOMIC _ASM_MK_NOP(K8_NOP5_ATOMIC)
#else
#define ASM_NOP1 _ASM_MK_NOP(GENERIC_NOP1)
#define ASM_NOP2 _ASM_MK_NOP(GENERIC_NOP2)
#define ASM_NOP3 _ASM_MK_NOP(GENERIC_NOP3)
#define ASM_NOP4 _ASM_MK_NOP(GENERIC_NOP4)
#define ASM_NOP5 _ASM_MK_NOP(GENERIC_NOP5)
#define ASM_NOP6 _ASM_MK_NOP(GENERIC_NOP6)
#define ASM_NOP7 _ASM_MK_NOP(GENERIC_NOP7)
#define ASM_NOP8 _ASM_MK_NOP(GENERIC_NOP8)
#define ASM_NOP5_ATOMIC _ASM_MK_NOP(GENERIC_NOP5_ATOMIC)
#endif
#define ASM_NOP1 _ASM_MK_NOP(BYTES_NOP1)
#define ASM_NOP2 _ASM_MK_NOP(BYTES_NOP2)
#define ASM_NOP3 _ASM_MK_NOP(BYTES_NOP3)
#define ASM_NOP4 _ASM_MK_NOP(BYTES_NOP4)
#define ASM_NOP5 _ASM_MK_NOP(BYTES_NOP5)
#define ASM_NOP6 _ASM_MK_NOP(BYTES_NOP6)
#define ASM_NOP7 _ASM_MK_NOP(BYTES_NOP7)
#define ASM_NOP8 _ASM_MK_NOP(BYTES_NOP8)
#define ASM_NOP_MAX 8
#define NOP_ATOMIC5 (ASM_NOP_MAX+1) /* Entry for the 5-byte atomic NOP */
#ifndef __ASSEMBLY__
extern const unsigned char * const *ideal_nops;
extern void arch_init_ideal_nops(void);
extern const unsigned char * const x86_nops[];
#endif
#endif /* _ASM_X86_NOPS_H */

4
arch/x86/include/asm/special_insns.h
View File

@ -214,7 +214,7 @@ static inline void clflush(volatile void *__p)
static inline void clflushopt(volatile void *__p)
{
alternative_io(".byte " __stringify(NOP_DS_PREFIX) "; clflush %P0",
alternative_io(".byte 0x3e; clflush %P0",
".byte 0x66; clflush %P0",
X86_FEATURE_CLFLUSHOPT,
"+m" (*(volatile char __force *)__p));
@ -225,7 +225,7 @@ static inline void clwb(volatile void *__p)
volatile struct { char x[64]; } *p = __p;
asm volatile(ALTERNATIVE_2(
".byte " __stringify(NOP_DS_PREFIX) "; clflush (%[pax])",
".byte 0x3e; clflush (%[pax])",
".byte 0x66; clflush (%[pax])", /* clflushopt (%%rax) */
X86_FEATURE_CLFLUSHOPT,
".byte 0x66, 0x0f, 0xae, 0x30", /* clwb (%%rax) */

200
arch/x86/kernel/alternative.c
View File

@ -75,186 +75,30 @@ do { \
} \
} while (0)
/*
* Each GENERIC_NOPX is of X bytes, and defined as an array of bytes
* that correspond to that nop. Getting from one nop to the next, we
* add to the array the offset that is equal to the sum of all sizes of
* nops preceding the one we are after.
*
* Note: The GENERIC_NOP5_ATOMIC is at the end, as it breaks the
* nice symmetry of sizes of the previous nops.
*/
#if defined(GENERIC_NOP1) && !defined(CONFIG_X86_64)
static const unsigned char intelnops[] =
const unsigned char x86nops[] =
{
GENERIC_NOP1,
GENERIC_NOP2,
GENERIC_NOP3,
GENERIC_NOP4,
GENERIC_NOP5,
GENERIC_NOP6,
GENERIC_NOP7,
GENERIC_NOP8,
GENERIC_NOP5_ATOMIC
BYTES_NOP1,
BYTES_NOP2,
BYTES_NOP3,
BYTES_NOP4,
BYTES_NOP5,
BYTES_NOP6,
BYTES_NOP7,
BYTES_NOP8,
};
static const unsigned char * const intel_nops[ASM_NOP_MAX+2] =
const unsigned char * const x86_nops[ASM_NOP_MAX+1] =
{
NULL,
intelnops,
intelnops + 1,
intelnops + 1 + 2,
intelnops + 1 + 2 + 3,
intelnops + 1 + 2 + 3 + 4,
intelnops + 1 + 2 + 3 + 4 + 5,
intelnops + 1 + 2 + 3 + 4 + 5 + 6,
intelnops + 1 + 2 + 3 + 4 + 5 + 6 + 7,
intelnops + 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8,
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,
};
#endif
#ifdef K8_NOP1
static const unsigned char k8nops[] =
{
K8_NOP1,
K8_NOP2,
K8_NOP3,
K8_NOP4,
K8_NOP5,
K8_NOP6,
K8_NOP7,
K8_NOP8,
K8_NOP5_ATOMIC
};
static const unsigned char * const k8_nops[ASM_NOP_MAX+2] =
{
NULL,
k8nops,
k8nops + 1,
k8nops + 1 + 2,
k8nops + 1 + 2 + 3,
k8nops + 1 + 2 + 3 + 4,
k8nops + 1 + 2 + 3 + 4 + 5,
k8nops + 1 + 2 + 3 + 4 + 5 + 6,
k8nops + 1 + 2 + 3 + 4 + 5 + 6 + 7,
k8nops + 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8,
};
#endif
#if defined(K7_NOP1) && !defined(CONFIG_X86_64)
static const unsigned char k7nops[] =
{
K7_NOP1,
K7_NOP2,
K7_NOP3,
K7_NOP4,
K7_NOP5,
K7_NOP6,
K7_NOP7,
K7_NOP8,
K7_NOP5_ATOMIC
};
static const unsigned char * const k7_nops[ASM_NOP_MAX+2] =
{
NULL,
k7nops,
k7nops + 1,
k7nops + 1 + 2,
k7nops + 1 + 2 + 3,
k7nops + 1 + 2 + 3 + 4,
k7nops + 1 + 2 + 3 + 4 + 5,
k7nops + 1 + 2 + 3 + 4 + 5 + 6,
k7nops + 1 + 2 + 3 + 4 + 5 + 6 + 7,
k7nops + 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8,
};
#endif
#ifdef P6_NOP1
static const unsigned char p6nops[] =
{
P6_NOP1,
P6_NOP2,
P6_NOP3,
P6_NOP4,
P6_NOP5,
P6_NOP6,
P6_NOP7,
P6_NOP8,
P6_NOP5_ATOMIC
};
static const unsigned char * const p6_nops[ASM_NOP_MAX+2] =
{
NULL,
p6nops,
p6nops + 1,
p6nops + 1 + 2,
p6nops + 1 + 2 + 3,
p6nops + 1 + 2 + 3 + 4,
p6nops + 1 + 2 + 3 + 4 + 5,
p6nops + 1 + 2 + 3 + 4 + 5 + 6,
p6nops + 1 + 2 + 3 + 4 + 5 + 6 + 7,
p6nops + 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8,
};
#endif
/* Initialize these to a safe default */
#ifdef CONFIG_X86_64
const unsigned char * const *ideal_nops = p6_nops;
#else
const unsigned char * const *ideal_nops = intel_nops;
#endif
void __init arch_init_ideal_nops(void)
{
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_INTEL:
/*
* Due to a decoder implementation quirk, some
* specific Intel CPUs actually perform better with
* the "k8_nops" than with the SDM-recommended NOPs.
*/
if (boot_cpu_data.x86 == 6 &&
boot_cpu_data.x86_model >= 0x0f &&
boot_cpu_data.x86_model != 0x1c &&
boot_cpu_data.x86_model != 0x26 &&
boot_cpu_data.x86_model != 0x27 &&
boot_cpu_data.x86_model < 0x30) {
ideal_nops = k8_nops;
} else if (boot_cpu_has(X86_FEATURE_NOPL)) {
ideal_nops = p6_nops;
} else {
#ifdef CONFIG_X86_64
ideal_nops = k8_nops;
#else
ideal_nops = intel_nops;
#endif
}
break;
case X86_VENDOR_HYGON:
ideal_nops = p6_nops;
return;
case X86_VENDOR_AMD:
if (boot_cpu_data.x86 > 0xf) {
ideal_nops = p6_nops;
return;
}
fallthrough;
default:
#ifdef CONFIG_X86_64
ideal_nops = k8_nops;
#else
if (boot_cpu_has(X86_FEATURE_K8))
ideal_nops = k8_nops;
else if (boot_cpu_has(X86_FEATURE_K7))
ideal_nops = k7_nops;
else
ideal_nops = intel_nops;
#endif
}
}
/* 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)
@ -263,7 +107,7 @@ static void __init_or_module add_nops(void *insns, unsigned int len)
unsigned int noplen = len;
if (noplen > ASM_NOP_MAX)
noplen = ASM_NOP_MAX;
memcpy(insns, ideal_nops[noplen], noplen);
memcpy(insns, x86_nops[noplen], noplen);
insns += noplen;
len -= noplen;
}
@ -1338,13 +1182,13 @@ static void text_poke_loc_init(struct text_poke_loc *tp, void *addr,
default: /* assume NOP */
switch (len) {
case 2: /* NOP2 -- emulate as JMP8+0 */
BUG_ON(memcmp(emulate, ideal_nops[len], len));
BUG_ON(memcmp(emulate, x86_nops[len], len));
tp->opcode = JMP8_INSN_OPCODE;
tp->rel32 = 0;
break;
case 5: /* NOP5 -- emulate as JMP32+0 */
BUG_ON(memcmp(emulate, ideal_nops[NOP_ATOMIC5], len));
BUG_ON(memcmp(emulate, x86_nops[len], len));
tp->opcode = JMP32_INSN_OPCODE;
tp->rel32 = 0;
break;

5
arch/x86/kernel/cpu/amd.c
View File

@ -628,11 +628,6 @@ static void early_init_amd(struct cpuinfo_x86 *c)
early_init_amd_mc(c);
#ifdef CONFIG_X86_32
if (c->x86 == 6)
set_cpu_cap(c, X86_FEATURE_K7);
#endif
if (c->x86 >= 0xf)
set_cpu_cap(c, X86_FEATURE_K8);

4
arch/x86/kernel/cpu/hygon.c
View File

@ -215,12 +215,12 @@ static void bsp_init_hygon(struct cpuinfo_x86 *c)
u32 ecx;
ecx = cpuid_ecx(0x8000001e);
nodes_per_socket = ((ecx >> 8) & 7) + 1;
__max_die_per_package = nodes_per_socket = ((ecx >> 8) & 7) + 1;
} else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) {
u64 value;
rdmsrl(MSR_FAM10H_NODE_ID, value);
nodes_per_socket = ((value >> 3) & 7) + 1;
__max_die_per_package = nodes_per_socket = ((value >> 3) & 7) + 1;
}
if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&

1
arch/x86/kernel/cpu/mce/intel.c
View File

@ -486,6 +486,7 @@ static void intel_ppin_init(struct cpuinfo_x86 *c)
case INTEL_FAM6_BROADWELL_X:
case INTEL_FAM6_SKYLAKE_X:
case INTEL_FAM6_ICELAKE_X:
case INTEL_FAM6_SAPPHIRERAPIDS_X:
case INTEL_FAM6_XEON_PHI_KNL:
case INTEL_FAM6_XEON_PHI_KNM:

4
arch/x86/kernel/ftrace.c
View File

@ -66,7 +66,7 @@ int ftrace_arch_code_modify_post_process(void)
static const char *ftrace_nop_replace(void)
{
return ideal_nops[NOP_ATOMIC5];
return x86_nops[5];
}
static const char *ftrace_call_replace(unsigned long ip, unsigned long addr)
@ -377,7 +377,7 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size)
ip = trampoline + (jmp_offset - start_offset);
if (WARN_ON(*(char *)ip != 0x75))
goto fail;
ret = copy_from_kernel_nofault(ip, ideal_nops[2], 2);
ret = copy_from_kernel_nofault(ip, x86_nops[2], 2);
if (ret < 0)
goto fail;
}

32
arch/x86/kernel/jump_label.c
View File

@ -28,10 +28,8 @@ static void bug_at(const void *ip, int line)
}
static const void *
__jump_label_set_jump_code(struct jump_entry *entry, enum jump_label_type type, int init)
__jump_label_set_jump_code(struct jump_entry *entry, enum jump_label_type type)
{
const unsigned char default_nop[] = { STATIC_KEY_INIT_NOP };
const unsigned char *ideal_nop = ideal_nops[NOP_ATOMIC5];
const void *expect, *code;
const void *addr, *dest;
int line;
@ -41,10 +39,8 @@ __jump_label_set_jump_code(struct jump_entry *entry, enum jump_label_type type,
code = text_gen_insn(JMP32_INSN_OPCODE, addr, dest);
if (init) {
expect = default_nop; line = __LINE__;
} else if (type == JUMP_LABEL_JMP) {
expect = ideal_nop; line = __LINE__;
if (type == JUMP_LABEL_JMP) {
expect = x86_nops[5]; line = __LINE__;
} else {
expect = code; line = __LINE__;
}
@ -53,7 +49,7 @@ __jump_label_set_jump_code(struct jump_entry *entry, enum jump_label_type type,
bug_at(addr, line);
if (type == JUMP_LABEL_NOP)
code = ideal_nop;
code = x86_nops[5];
return code;
}
@ -62,7 +58,7 @@ static inline void __jump_label_transform(struct jump_entry *entry,
enum jump_label_type type,
int init)
{
const void *opcode = __jump_label_set_jump_code(entry, type, init);
const void *opcode = __jump_label_set_jump_code(entry, type);
/*
* As long as only a single processor is running and the code is still
@ -113,7 +109,7 @@ bool arch_jump_label_transform_queue(struct jump_entry *entry,
}
mutex_lock(&text_mutex);
opcode = __jump_label_set_jump_code(entry, type, 0);
opcode = __jump_label_set_jump_code(entry, type);
text_poke_queue((void *)jump_entry_code(entry),
opcode, JUMP_LABEL_NOP_SIZE, NULL);
mutex_unlock(&text_mutex);
@ -136,22 +132,6 @@ static enum {
__init_or_module void arch_jump_label_transform_static(struct jump_entry *entry,
enum jump_label_type type)
{
/*
* This function is called at boot up and when modules are
* first loaded. Check if the default nop, the one that is
* inserted at compile time, is the ideal nop. If it is, then
* we do not need to update the nop, and we can leave it as is.
* If it is not, then we need to update the nop to the ideal nop.
*/
if (jlstate == JL_STATE_START) {
const unsigned char default_nop[] = { STATIC_KEY_INIT_NOP };
const unsigned char *ideal_nop = ideal_nops[NOP_ATOMIC5];
if (memcmp(ideal_nop, default_nop, 5) != 0)
jlstate = JL_STATE_UPDATE;
else
jlstate = JL_STATE_NO_UPDATE;
}
if (jlstate == JL_STATE_UPDATE)
jump_label_transform(entry, type, 1);
}

2
arch/x86/kernel/kprobes/core.c
View File

@ -235,7 +235,7 @@ __recover_probed_insn(kprobe_opcode_t *buf, unsigned long addr)
return 0UL;
if (faddr)
memcpy(buf, ideal_nops[NOP_ATOMIC5], 5);
memcpy(buf, x86_nops[5], 5);
else
buf[0] = kp->opcode;
return (unsigned long)buf;

1
arch/x86/kernel/setup.c
View File

@ -822,7 +822,6 @@ void __init setup_arch(char **cmdline_p)
idt_setup_early_traps();
early_cpu_init();
arch_init_ideal_nops();
jump_label_init();
static_call_init();
early_ioremap_init();

4
arch/x86/kernel/static_call.c
View File

@ -34,7 +34,7 @@ static void __ref __static_call_transform(void *insn, enum insn_type type, void
break;
case NOP:
code = ideal_nops[NOP_ATOMIC5];
code = x86_nops[5];
break;
case JMP:
@ -66,7 +66,7 @@ static void __static_call_validate(void *insn, bool tail)
return;
} else {
if (opcode == CALL_INSN_OPCODE ||
!memcmp(insn, ideal_nops[NOP_ATOMIC5], 5) ||
!memcmp(insn, x86_nops[5], 5) ||
!memcmp(insn, xor5rax, 5))
return;
}

10
arch/x86/net/bpf_jit_comp.c
View File

@ -282,7 +282,7 @@ static void emit_prologue(u8 **pprog, u32 stack_depth, bool ebpf_from_cbpf,
/* BPF trampoline can be made to work without these nops,
* but let's waste 5 bytes for now and optimize later
*/
memcpy(prog, ideal_nops[NOP_ATOMIC5], cnt);
memcpy(prog, x86_nops[5], cnt);
prog += cnt;
if (!ebpf_from_cbpf) {
if (tail_call_reachable && !is_subprog)
@ -330,7 +330,7 @@ static int __bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t,
void *old_addr, void *new_addr,
const bool text_live)
{
const u8 *nop_insn = ideal_nops[NOP_ATOMIC5];
const u8 *nop_insn = x86_nops[5];
u8 old_insn[X86_PATCH_SIZE];
u8 new_insn[X86_PATCH_SIZE];
u8 *prog;
@ -560,7 +560,7 @@ static void emit_bpf_tail_call_direct(struct bpf_jit_poke_descriptor *poke,
if (stack_depth)
EMIT3_off32(0x48, 0x81, 0xC4, round_up(stack_depth, 8));
memcpy(prog, ideal_nops[NOP_ATOMIC5], X86_PATCH_SIZE);
memcpy(prog, x86_nops[5], X86_PATCH_SIZE);
prog += X86_PATCH_SIZE;
/* out: */
@ -881,7 +881,7 @@ static int emit_nops(u8 **pprog, int len)
noplen = ASM_NOP_MAX;
for (i = 0; i < noplen; i++)
EMIT1(ideal_nops[noplen][i]);
EMIT1(x86_nops[noplen][i]);
len -= noplen;
}
@ -2012,7 +2012,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
/* remember return value in a stack for bpf prog to access */
emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -8);
im->ip_after_call = prog;
memcpy(prog, ideal_nops[NOP_ATOMIC5], X86_PATCH_SIZE);
memcpy(prog, x86_nops[5], X86_PATCH_SIZE);
prog += X86_PATCH_SIZE;
}

81
tools/arch/x86/include/asm/nops.h Normal file
View File

@ -0,0 +1,81 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_NOPS_H
#define _ASM_X86_NOPS_H
/*
* Define nops for use with alternative() and for tracing.
*/
#ifndef CONFIG_64BIT
/*
* Generic 32bit nops from GAS:
*
* 1: nop
* 2: movl %esi,%esi
* 3: leal 0x0(%esi),%esi
* 4: leal 0x0(%esi,%eiz,1),%esi
* 5: leal %ds:0x0(%esi,%eiz,1),%esi
* 6: leal 0x0(%esi),%esi
* 7: leal 0x0(%esi,%eiz,1),%esi
* 8: leal %ds:0x0(%esi,%eiz,1),%esi
*
* Except 5 and 8, which are DS prefixed 4 and 7 resp, where GAS would emit 2
* nop instructions.
*/
#define BYTES_NOP1 0x90
#define BYTES_NOP2 0x89,0xf6
#define BYTES_NOP3 0x8d,0x76,0x00
#define BYTES_NOP4 0x8d,0x74,0x26,0x00
#define BYTES_NOP5 0x3e,BYTES_NOP4
#define BYTES_NOP6 0x8d,0xb6,0x00,0x00,0x00,0x00
#define BYTES_NOP7 0x8d,0xb4,0x26,0x00,0x00,0x00,0x00
#define BYTES_NOP8 0x3e,BYTES_NOP7
#else
/*
* Generic 64bit nops from GAS:
*
* 1: nop
* 2: osp nop
* 3: nopl (%eax)
* 4: nopl 0x00(%eax)
* 5: nopl 0x00(%eax,%eax,1)
* 6: osp nopl 0x00(%eax,%eax,1)
* 7: nopl 0x00000000(%eax)
* 8: nopl 0x00000000(%eax,%eax,1)
*/
#define BYTES_NOP1 0x90
#define BYTES_NOP2 0x66,BYTES_NOP1
#define BYTES_NOP3 0x0f,0x1f,0x00
#define BYTES_NOP4 0x0f,0x1f,0x40,0x00
#define BYTES_NOP5 0x0f,0x1f,0x44,0x00,0x00
#define BYTES_NOP6 0x66,BYTES_NOP5
#define BYTES_NOP7 0x0f,0x1f,0x80,0x00,0x00,0x00,0x00
#define BYTES_NOP8 0x0f,0x1f,0x84,0x00,0x00,0x00,0x00,0x00
#endif /* CONFIG_64BIT */
#ifdef __ASSEMBLY__
#define _ASM_MK_NOP(x) .byte x
#else
#define _ASM_MK_NOP(x) ".byte " __stringify(x) "\n"
#endif
#define ASM_NOP1 _ASM_MK_NOP(BYTES_NOP1)
#define ASM_NOP2 _ASM_MK_NOP(BYTES_NOP2)
#define ASM_NOP3 _ASM_MK_NOP(BYTES_NOP3)
#define ASM_NOP4 _ASM_MK_NOP(BYTES_NOP4)
#define ASM_NOP5 _ASM_MK_NOP(BYTES_NOP5)
#define ASM_NOP6 _ASM_MK_NOP(BYTES_NOP6)
#define ASM_NOP7 _ASM_MK_NOP(BYTES_NOP7)
#define ASM_NOP8 _ASM_MK_NOP(BYTES_NOP8)
#define ASM_NOP_MAX 8
#ifndef __ASSEMBLY__
extern const unsigned char * const x86_nops[];
#endif
#endif /* _ASM_X86_NOPS_H */

13
tools/objtool/arch/x86/decode.c
View File

@ -11,6 +11,9 @@
#include "../../../arch/x86/lib/inat.c"
#include "../../../arch/x86/lib/insn.c"
#define CONFIG_64BIT 1
#include <asm/nops.h>
#include <asm/orc_types.h>
#include <objtool/check.h>
#include <objtool/elf.h>
@ -595,11 +598,11 @@ void arch_initial_func_cfi_state(struct cfi_init_state *state)
const char *arch_nop_insn(int len)
{
static const char nops[5][5] = {
/* 1 */ { 0x90 },
/* 2 */ { 0x66, 0x90 },
/* 3 */ { 0x0f, 0x1f, 0x00 },
/* 4 */ { 0x0f, 0x1f, 0x40, 0x00 },
/* 5 */ { 0x0f, 0x1f, 0x44, 0x00, 0x00 },
{ BYTES_NOP1 },
{ BYTES_NOP2 },
{ BYTES_NOP3 },
{ BYTES_NOP4 },
{ BYTES_NOP5 },
};
if (len < 1 || len > 5) {

1
tools/objtool/sync-check.sh
View File

@ -10,6 +10,7 @@ FILES="include/linux/objtool.h"
if [ "$SRCARCH" = "x86" ]; then
FILES="$FILES
arch/x86/include/asm/nops.h
arch/x86/include/asm/inat_types.h
arch/x86/include/asm/orc_types.h
arch/x86/include/asm/emulate_prefix.h