linux_dsm_epyc7002/arch/x86/include/asm/cpufeature.h
Thomas Gleixner 6cbd2171e8 x86/cpufeatures: Make CPU bugs sticky
There is currently no way to force CPU bug bits like CPU feature bits. That
makes it impossible to set a bug bit once at boot and have it stick for all
upcoming CPUs.

Extend the force set/clear arrays to handle bug bits as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.992156574@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-17 14:27:53 +01:00

220 lines
7.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_CPUFEATURE_H
#define _ASM_X86_CPUFEATURE_H
#include <asm/processor.h>
#if defined(__KERNEL__) && !defined(__ASSEMBLY__)
#include <asm/asm.h>
#include <linux/bitops.h>
enum cpuid_leafs
{
CPUID_1_EDX = 0,
CPUID_8000_0001_EDX,
CPUID_8086_0001_EDX,
CPUID_LNX_1,
CPUID_1_ECX,
CPUID_C000_0001_EDX,
CPUID_8000_0001_ECX,
CPUID_LNX_2,
CPUID_LNX_3,
CPUID_7_0_EBX,
CPUID_D_1_EAX,
CPUID_F_0_EDX,
CPUID_F_1_EDX,
CPUID_8000_0008_EBX,
CPUID_6_EAX,
CPUID_8000_000A_EDX,
CPUID_7_ECX,
CPUID_8000_0007_EBX,
};
#ifdef CONFIG_X86_FEATURE_NAMES
extern const char * const x86_cap_flags[NCAPINTS*32];
extern const char * const x86_power_flags[32];
#define X86_CAP_FMT "%s"
#define x86_cap_flag(flag) x86_cap_flags[flag]
#else
#define X86_CAP_FMT "%d:%d"
#define x86_cap_flag(flag) ((flag) >> 5), ((flag) & 31)
#endif
/*
* In order to save room, we index into this array by doing
* X86_BUG_<name> - NCAPINTS*32.
*/
extern const char * const x86_bug_flags[NBUGINTS*32];
#define test_cpu_cap(c, bit) \
test_bit(bit, (unsigned long *)((c)->x86_capability))
/*
* There are 32 bits/features in each mask word. The high bits
* (selected with (bit>>5) give us the word number and the low 5
* bits give us the bit/feature number inside the word.
* (1UL<<((bit)&31) gives us a mask for the feature_bit so we can
* see if it is set in the mask word.
*/
#define CHECK_BIT_IN_MASK_WORD(maskname, word, bit) \
(((bit)>>5)==(word) && (1UL<<((bit)&31) & maskname##word ))
#define REQUIRED_MASK_BIT_SET(feature_bit) \
( CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 0, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 1, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 2, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 3, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 4, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 5, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 6, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 7, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 8, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 9, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 10, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 11, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 12, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 13, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 14, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 15, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 16, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 17, feature_bit) || \
REQUIRED_MASK_CHECK || \
BUILD_BUG_ON_ZERO(NCAPINTS != 18))
#define DISABLED_MASK_BIT_SET(feature_bit) \
( CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 0, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 1, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 2, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 3, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 4, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 5, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 6, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 7, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 8, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 9, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 10, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 11, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 12, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 13, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 14, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 15, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 16, feature_bit) || \
CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 17, feature_bit) || \
DISABLED_MASK_CHECK || \
BUILD_BUG_ON_ZERO(NCAPINTS != 18))
#define cpu_has(c, bit) \
(__builtin_constant_p(bit) && REQUIRED_MASK_BIT_SET(bit) ? 1 : \
test_cpu_cap(c, bit))
#define this_cpu_has(bit) \
(__builtin_constant_p(bit) && REQUIRED_MASK_BIT_SET(bit) ? 1 : \
x86_this_cpu_test_bit(bit, (unsigned long *)&cpu_info.x86_capability))
/*
* This macro is for detection of features which need kernel
* infrastructure to be used. It may *not* directly test the CPU
* itself. Use the cpu_has() family if you want true runtime
* testing of CPU features, like in hypervisor code where you are
* supporting a possible guest feature where host support for it
* is not relevant.
*/
#define cpu_feature_enabled(bit) \
(__builtin_constant_p(bit) && DISABLED_MASK_BIT_SET(bit) ? 0 : static_cpu_has(bit))
#define boot_cpu_has(bit) cpu_has(&boot_cpu_data, bit)
#define set_cpu_cap(c, bit) set_bit(bit, (unsigned long *)((c)->x86_capability))
extern void setup_clear_cpu_cap(unsigned int bit);
extern void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int bit);
#define setup_force_cpu_cap(bit) do { \
set_cpu_cap(&boot_cpu_data, bit); \
set_bit(bit, (unsigned long *)cpu_caps_set); \
} while (0)
#define setup_force_cpu_bug(bit) setup_force_cpu_cap(bit)
#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_X86_FAST_FEATURE_TESTS)
/*
* Static testing of CPU features. Used the same as boot_cpu_has().
* These will statically patch the target code for additional
* performance.
*/
static __always_inline __pure bool _static_cpu_has(u16 bit)
{
asm_volatile_goto("1: jmp 6f\n"
"2:\n"
".skip -(((5f-4f) - (2b-1b)) > 0) * "
"((5f-4f) - (2b-1b)),0x90\n"
"3:\n"
".section .altinstructions,\"a\"\n"
" .long 1b - .\n" /* src offset */
" .long 4f - .\n" /* repl offset */
" .word %P1\n" /* always replace */
" .byte 3b - 1b\n" /* src len */
" .byte 5f - 4f\n" /* repl len */
" .byte 3b - 2b\n" /* pad len */
".previous\n"
".section .altinstr_replacement,\"ax\"\n"
"4: jmp %l[t_no]\n"
"5:\n"
".previous\n"
".section .altinstructions,\"a\"\n"
" .long 1b - .\n" /* src offset */
" .long 0\n" /* no replacement */
" .word %P0\n" /* feature bit */
" .byte 3b - 1b\n" /* src len */
" .byte 0\n" /* repl len */
" .byte 0\n" /* pad len */
".previous\n"
".section .altinstr_aux,\"ax\"\n"
"6:\n"
" testb %[bitnum],%[cap_byte]\n"
" jnz %l[t_yes]\n"
" jmp %l[t_no]\n"
".previous\n"
: : "i" (bit), "i" (X86_FEATURE_ALWAYS),
[bitnum] "i" (1 << (bit & 7)),
[cap_byte] "m" (((const char *)boot_cpu_data.x86_capability)[bit >> 3])
: : t_yes, t_no);
t_yes:
return true;
t_no:
return false;
}
#define static_cpu_has(bit) \
( \
__builtin_constant_p(boot_cpu_has(bit)) ? \
boot_cpu_has(bit) : \
_static_cpu_has(bit) \
)
#else
/*
* Fall back to dynamic for gcc versions which don't support asm goto. Should be
* a minority now anyway.
*/
#define static_cpu_has(bit) boot_cpu_has(bit)
#endif
#define cpu_has_bug(c, bit) cpu_has(c, (bit))
#define set_cpu_bug(c, bit) set_cpu_cap(c, (bit))
#define clear_cpu_bug(c, bit) clear_cpu_cap(c, (bit))
#define static_cpu_has_bug(bit) static_cpu_has((bit))
#define boot_cpu_has_bug(bit) cpu_has_bug(&boot_cpu_data, (bit))
#define boot_cpu_set_bug(bit) set_cpu_cap(&boot_cpu_data, (bit))
#define MAX_CPU_FEATURES (NCAPINTS * 32)
#define cpu_have_feature boot_cpu_has
#define CPU_FEATURE_TYPEFMT "x86,ven%04Xfam%04Xmod%04X"
#define CPU_FEATURE_TYPEVAL boot_cpu_data.x86_vendor, boot_cpu_data.x86, \
boot_cpu_data.x86_model
#endif /* defined(__KERNEL__) && !defined(__ASSEMBLY__) */
#endif /* _ASM_X86_CPUFEATURE_H */