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x86/microcode/intel: Use *wrmsrl variants
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... and drop the 32-bit casting games which we had to do at the time
because wrmsr() was unforgiving then, see c3fd0bd5e19a from the
full history tree:

  commit c3fd0bd5e19aaff9cdd104edff136a2023db657e
  Author: Linus Torvalds <torvalds@home.osdl.org>
  Date:   Tue Feb 17 23:23:41 2004 -0800

    Fix up the microcode update on regular 32-bit x86. Our wrmsr()
    is a bit unforgiving and really doesn't like 64-bit values.
    ...

Tested-by: Thomas Voegtle <tv@lio96.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
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/1454499225-21544-13-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Borislav Petkov authored and Ingo Molnar committed Feb 9, 2016
1 parent 26cbaa4 commit c416e61
Showing 1 changed file with 5 additions and 9 deletions.
14 changes: 5 additions & 9 deletions arch/x86/kernel/cpu/microcode/intel.c
Original file line number Diff line number Diff line change
Expand Up @@ -370,7 +370,7 @@ static int collect_cpu_info_early(struct ucode_cpu_info *uci)
native_rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
csig.pf = 1 << ((val[1] >> 18) & 7);
}
native_wrmsr(MSR_IA32_UCODE_REV, 0, 0);
native_wrmsrl(MSR_IA32_UCODE_REV, 0);

/* As documented in the SDM: Do a CPUID 1 here */
sync_core();
Expand Down Expand Up @@ -648,10 +648,8 @@ static int apply_microcode_early(struct ucode_cpu_info *uci, bool early)
return 0;

/* write microcode via MSR 0x79 */
native_wrmsr(MSR_IA32_UCODE_WRITE,
(unsigned long)mc->bits,
(unsigned long)mc->bits >> 16 >> 16);
native_wrmsr(MSR_IA32_UCODE_REV, 0, 0);
native_wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
native_wrmsrl(MSR_IA32_UCODE_REV, 0);

/* As documented in the SDM: Do a CPUID 1 here */
sync_core();
Expand Down Expand Up @@ -860,10 +858,8 @@ static int apply_microcode_intel(int cpu)
return 0;

/* write microcode via MSR 0x79 */
wrmsr(MSR_IA32_UCODE_WRITE,
(unsigned long) mc->bits,
(unsigned long) mc->bits >> 16 >> 16);
wrmsr(MSR_IA32_UCODE_REV, 0, 0);
wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
wrmsrl(MSR_IA32_UCODE_REV, 0);

/* As documented in the SDM: Do a CPUID 1 here */
sync_core();
Expand Down

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