Commit c9cdd9a6 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'x86/mpx' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cpufeature and mpx updates from Peter Anvin:
 "This includes the basic infrastructure for MPX (Memory Protection
  Extensions) support, but does not include MPX support itself.  It is,
  however, a prerequisite for KVM support for MPX, which I believe will
  be pushed later this merge window by the KVM team.

  This includes moving the functionality in
  futex_atomic_cmpxchg_inatomic() into a new function in uaccess.h so it
  can be reused - this will be used by the final MPX patches.

  The actual MPX functionality (map management and so on) will be pushed
  in a future merge window, when ready"

* 'x86/mpx' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/intel/mpx: Remove unused LWP structure
  x86, mpx: Add MPX related opcodes to the x86 opcode map
  x86: replace futex_atomic_cmpxchg_inatomic() with user_atomic_cmpxchg_inatomic
  x86: add user_atomic_cmpxchg_inatomic at uaccess.h
  x86, xsave: Support eager-only xsave features, add MPX support
  x86, cpufeature: Define the Intel MPX feature flag
parents f4bcd8cc 741e3902
......@@ -216,6 +216,7 @@
#define X86_FEATURE_ERMS (9*32+ 9) /* Enhanced REP MOVSB/STOSB */
#define X86_FEATURE_INVPCID (9*32+10) /* Invalidate Processor Context ID */
#define X86_FEATURE_RTM (9*32+11) /* Restricted Transactional Memory */
#define X86_FEATURE_MPX (9*32+14) /* Memory Protection Extension */
#define X86_FEATURE_RDSEED (9*32+18) /* The RDSEED instruction */
#define X86_FEATURE_ADX (9*32+19) /* The ADCX and ADOX instructions */
#define X86_FEATURE_SMAP (9*32+20) /* Supervisor Mode Access Prevention */
......
......@@ -110,26 +110,7 @@ static inline int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
u32 oldval, u32 newval)
{
int ret = 0;
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
return -EFAULT;
asm volatile("\t" ASM_STAC "\n"
"1:\t" LOCK_PREFIX "cmpxchgl %4, %2\n"
"2:\t" ASM_CLAC "\n"
"\t.section .fixup, \"ax\"\n"
"3:\tmov %3, %0\n"
"\tjmp 2b\n"
"\t.previous\n"
_ASM_EXTABLE(1b, 3b)
: "+r" (ret), "=a" (oldval), "+m" (*uaddr)
: "i" (-EFAULT), "r" (newval), "1" (oldval)
: "memory"
);
*uval = oldval;
return ret;
return user_atomic_cmpxchg_inatomic(uval, uaddr, oldval, newval);
}
#endif
......
......@@ -370,6 +370,20 @@ struct ymmh_struct {
u32 ymmh_space[64];
};
/* We don't support LWP yet: */
struct lwp_struct {
u8 reserved[128];
};
struct bndregs_struct {
u64 bndregs[8];
} __packed;
struct bndcsr_struct {
u64 cfg_reg_u;
u64 status_reg;
} __packed;
struct xsave_hdr_struct {
u64 xstate_bv;
u64 reserved1[2];
......@@ -380,6 +394,9 @@ struct xsave_struct {
struct i387_fxsave_struct i387;
struct xsave_hdr_struct xsave_hdr;
struct ymmh_struct ymmh;
struct lwp_struct lwp;
struct bndregs_struct bndregs;
struct bndcsr_struct bndcsr;
/* new processor state extensions will go here */
} __attribute__ ((packed, aligned (64)));
......
......@@ -533,6 +533,98 @@ extern __must_check long strnlen_user(const char __user *str, long n);
unsigned long __must_check clear_user(void __user *mem, unsigned long len);
unsigned long __must_check __clear_user(void __user *mem, unsigned long len);
extern void __cmpxchg_wrong_size(void)
__compiletime_error("Bad argument size for cmpxchg");
#define __user_atomic_cmpxchg_inatomic(uval, ptr, old, new, size) \
({ \
int __ret = 0; \
__typeof__(ptr) __uval = (uval); \
__typeof__(*(ptr)) __old = (old); \
__typeof__(*(ptr)) __new = (new); \
switch (size) { \
case 1: \
{ \
asm volatile("\t" ASM_STAC "\n" \
"1:\t" LOCK_PREFIX "cmpxchgb %4, %2\n" \
"2:\t" ASM_CLAC "\n" \
"\t.section .fixup, \"ax\"\n" \
"3:\tmov %3, %0\n" \
"\tjmp 2b\n" \
"\t.previous\n" \
_ASM_EXTABLE(1b, 3b) \
: "+r" (__ret), "=a" (__old), "+m" (*(ptr)) \
: "i" (-EFAULT), "q" (__new), "1" (__old) \
: "memory" \
); \
break; \
} \
case 2: \
{ \
asm volatile("\t" ASM_STAC "\n" \
"1:\t" LOCK_PREFIX "cmpxchgw %4, %2\n" \
"2:\t" ASM_CLAC "\n" \
"\t.section .fixup, \"ax\"\n" \
"3:\tmov %3, %0\n" \
"\tjmp 2b\n" \
"\t.previous\n" \
_ASM_EXTABLE(1b, 3b) \
: "+r" (__ret), "=a" (__old), "+m" (*(ptr)) \
: "i" (-EFAULT), "r" (__new), "1" (__old) \
: "memory" \
); \
break; \
} \
case 4: \
{ \
asm volatile("\t" ASM_STAC "\n" \
"1:\t" LOCK_PREFIX "cmpxchgl %4, %2\n" \
"2:\t" ASM_CLAC "\n" \
"\t.section .fixup, \"ax\"\n" \
"3:\tmov %3, %0\n" \
"\tjmp 2b\n" \
"\t.previous\n" \
_ASM_EXTABLE(1b, 3b) \
: "+r" (__ret), "=a" (__old), "+m" (*(ptr)) \
: "i" (-EFAULT), "r" (__new), "1" (__old) \
: "memory" \
); \
break; \
} \
case 8: \
{ \
if (!IS_ENABLED(CONFIG_X86_64)) \
__cmpxchg_wrong_size(); \
\
asm volatile("\t" ASM_STAC "\n" \
"1:\t" LOCK_PREFIX "cmpxchgq %4, %2\n" \
"2:\t" ASM_CLAC "\n" \
"\t.section .fixup, \"ax\"\n" \
"3:\tmov %3, %0\n" \
"\tjmp 2b\n" \
"\t.previous\n" \
_ASM_EXTABLE(1b, 3b) \
: "+r" (__ret), "=a" (__old), "+m" (*(ptr)) \
: "i" (-EFAULT), "r" (__new), "1" (__old) \
: "memory" \
); \
break; \
} \
default: \
__cmpxchg_wrong_size(); \
} \
*__uval = __old; \
__ret; \
})
#define user_atomic_cmpxchg_inatomic(uval, ptr, old, new) \
({ \
access_ok(VERIFY_WRITE, (ptr), sizeof(*(ptr))) ? \
__user_atomic_cmpxchg_inatomic((uval), (ptr), \
(old), (new), sizeof(*(ptr))) : \
-EFAULT; \
})
/*
* movsl can be slow when source and dest are not both 8-byte aligned
*/
......
......@@ -9,6 +9,8 @@
#define XSTATE_FP 0x1
#define XSTATE_SSE 0x2
#define XSTATE_YMM 0x4
#define XSTATE_BNDREGS 0x8
#define XSTATE_BNDCSR 0x10
#define XSTATE_FPSSE (XSTATE_FP | XSTATE_SSE)
......@@ -20,10 +22,14 @@
#define XSAVE_YMM_SIZE 256
#define XSAVE_YMM_OFFSET (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET)
/*
* These are the features that the OS can handle currently.
*/
#define XCNTXT_MASK (XSTATE_FP | XSTATE_SSE | XSTATE_YMM)
/* Supported features which support lazy state saving */
#define XSTATE_LAZY (XSTATE_FP | XSTATE_SSE | XSTATE_YMM)
/* Supported features which require eager state saving */
#define XSTATE_EAGER (XSTATE_BNDREGS | XSTATE_BNDCSR)
/* All currently supported features */
#define XCNTXT_MASK (XSTATE_LAZY | XSTATE_EAGER)
#ifdef CONFIG_X86_64
#define REX_PREFIX "0x48, "
......
......@@ -562,6 +562,16 @@ static void __init xstate_enable_boot_cpu(void)
if (cpu_has_xsaveopt && eagerfpu != DISABLE)
eagerfpu = ENABLE;
if (pcntxt_mask & XSTATE_EAGER) {
if (eagerfpu == DISABLE) {
pr_err("eagerfpu not present, disabling some xstate features: 0x%llx\n",
pcntxt_mask & XSTATE_EAGER);
pcntxt_mask &= ~XSTATE_EAGER;
} else {
eagerfpu = ENABLE;
}
}
pr_info("enabled xstate_bv 0x%llx, cntxt size 0x%x\n",
pcntxt_mask, xstate_size);
}
......
......@@ -346,8 +346,8 @@ AVXcode: 1
17: vmovhps Mq,Vq (v1) | vmovhpd Mq,Vq (66),(v1)
18: Grp16 (1A)
19:
1a:
1b:
1a: BNDCL Ev,Gv | BNDCU Ev,Gv | BNDMOV Gv,Ev | BNDLDX Gv,Ev,Gv
1b: BNDCN Ev,Gv | BNDMOV Ev,Gv | BNDMK Gv,Ev | BNDSTX Ev,GV,Gv
1c:
1d:
1e:
......
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