linux-brain/arch/x86/include/asm/microcode.h
Borislav Petkov 06b8534cb7 x86/microcode: Rework microcode loading
Yeah, I know, I know, this is a huuge patch and reviewing it is hard.

Sorry but this is the only way I could think of in which I can rewrite
the microcode patches loading procedure without breaking (knowingly) the
driver.

So maybe this patch is easier to review if one looks at the files after
the patch has been applied instead at the diff. Because then it becomes
pretty obvious:

* The BSP-loading path - load_ucode_bsp() is working independently from
  the AP path now and it doesn't save any pointers or patches anymore -
  it solely parses the builtin or initrd microcode and applies the patch.
  That's it.

This fixes the CONFIG_RANDOMIZE_MEMORY offset fun more solidly.

* The AP-loading path - load_ucode_ap() then goes and scans
  builtin/initrd *again* for the microcode patches but it caches them this
  time so that we don't have to do that scan on each AP but only once.

This simplifies the code considerably.

Then, when we save the microcode from the initrd/builtin, we go and
add the relevant patches to our own cache. The AMD side did do that
and now the Intel side does it too. So no more pointer copying and
blabla, we save the microcode patches ourselves and are independent from
initrd/builtin.

This whole conversion gives us other benefits like unifying the
initrd parsing into a single function: find_microcode_in_initrd() is
used by both.

The diffstat speaks for itself: 456 insertions(+), 695 deletions(-)

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161025095522.11964-12-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-25 12:28:59 +02:00

153 lines
4.0 KiB
C

#ifndef _ASM_X86_MICROCODE_H
#define _ASM_X86_MICROCODE_H
#include <asm/cpu.h>
#include <linux/earlycpio.h>
#include <linux/initrd.h>
#define native_rdmsr(msr, val1, val2) \
do { \
u64 __val = native_read_msr((msr)); \
(void)((val1) = (u32)__val); \
(void)((val2) = (u32)(__val >> 32)); \
} while (0)
#define native_wrmsr(msr, low, high) \
native_write_msr(msr, low, high)
#define native_wrmsrl(msr, val) \
native_write_msr((msr), \
(u32)((u64)(val)), \
(u32)((u64)(val) >> 32))
struct ucode_patch {
struct list_head plist;
void *data; /* Intel uses only this one */
u32 patch_id;
u16 equiv_cpu;
};
extern struct list_head microcode_cache;
struct cpu_signature {
unsigned int sig;
unsigned int pf;
unsigned int rev;
};
struct device;
enum ucode_state { UCODE_ERROR, UCODE_OK, UCODE_NFOUND };
struct microcode_ops {
enum ucode_state (*request_microcode_user) (int cpu,
const void __user *buf, size_t size);
enum ucode_state (*request_microcode_fw) (int cpu, struct device *,
bool refresh_fw);
void (*microcode_fini_cpu) (int cpu);
/*
* The generic 'microcode_core' part guarantees that
* the callbacks below run on a target cpu when they
* are being called.
* See also the "Synchronization" section in microcode_core.c.
*/
int (*apply_microcode) (int cpu);
int (*collect_cpu_info) (int cpu, struct cpu_signature *csig);
};
struct ucode_cpu_info {
struct cpu_signature cpu_sig;
int valid;
void *mc;
};
extern struct ucode_cpu_info ucode_cpu_info[];
struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa);
#ifdef CONFIG_MICROCODE_INTEL
extern struct microcode_ops * __init init_intel_microcode(void);
#else
static inline struct microcode_ops * __init init_intel_microcode(void)
{
return NULL;
}
#endif /* CONFIG_MICROCODE_INTEL */
#ifdef CONFIG_MICROCODE_AMD
extern struct microcode_ops * __init init_amd_microcode(void);
extern void __exit exit_amd_microcode(void);
#else
static inline struct microcode_ops * __init init_amd_microcode(void)
{
return NULL;
}
static inline void __exit exit_amd_microcode(void) {}
#endif
#define MAX_UCODE_COUNT 128
#define QCHAR(a, b, c, d) ((a) + ((b) << 8) + ((c) << 16) + ((d) << 24))
#define CPUID_INTEL1 QCHAR('G', 'e', 'n', 'u')
#define CPUID_INTEL2 QCHAR('i', 'n', 'e', 'I')
#define CPUID_INTEL3 QCHAR('n', 't', 'e', 'l')
#define CPUID_AMD1 QCHAR('A', 'u', 't', 'h')
#define CPUID_AMD2 QCHAR('e', 'n', 't', 'i')
#define CPUID_AMD3 QCHAR('c', 'A', 'M', 'D')
#define CPUID_IS(a, b, c, ebx, ecx, edx) \
(!((ebx ^ (a))|(edx ^ (b))|(ecx ^ (c))))
/*
* In early loading microcode phase on BSP, boot_cpu_data is not set up yet.
* x86_cpuid_vendor() gets vendor id for BSP.
*
* In 32 bit AP case, accessing boot_cpu_data needs linear address. To simplify
* coding, we still use x86_cpuid_vendor() to get vendor id for AP.
*
* x86_cpuid_vendor() gets vendor information directly from CPUID.
*/
static inline int x86_cpuid_vendor(void)
{
u32 eax = 0x00000000;
u32 ebx, ecx = 0, edx;
native_cpuid(&eax, &ebx, &ecx, &edx);
if (CPUID_IS(CPUID_INTEL1, CPUID_INTEL2, CPUID_INTEL3, ebx, ecx, edx))
return X86_VENDOR_INTEL;
if (CPUID_IS(CPUID_AMD1, CPUID_AMD2, CPUID_AMD3, ebx, ecx, edx))
return X86_VENDOR_AMD;
return X86_VENDOR_UNKNOWN;
}
static inline unsigned int x86_cpuid_family(void)
{
u32 eax = 0x00000001;
u32 ebx, ecx = 0, edx;
native_cpuid(&eax, &ebx, &ecx, &edx);
return x86_family(eax);
}
#ifdef CONFIG_MICROCODE
int __init microcode_init(void);
extern void __init load_ucode_bsp(void);
extern void load_ucode_ap(void);
void reload_early_microcode(void);
extern bool get_builtin_firmware(struct cpio_data *cd, const char *name);
#else
static inline int __init microcode_init(void) { return 0; };
static inline void __init load_ucode_bsp(void) { }
static inline void load_ucode_ap(void) { }
static inline void reload_early_microcode(void) { }
static inline bool
get_builtin_firmware(struct cpio_data *cd, const char *name) { return false; }
#endif
#endif /* _ASM_X86_MICROCODE_H */