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Commit b51ef52d authored by Laura Abbott's avatar Laura Abbott Committed by Ingo Molnar
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x86/cpu: Restore MSR_IA32_ENERGY_PERF_BIAS after resume



MSR_IA32_ENERGY_PERF_BIAS is lost after suspend/resume:

	x86_energy_perf_policy -r before

	cpu0: 0x0000000000000006
	cpu1: 0x0000000000000006
	cpu2: 0x0000000000000006
	cpu3: 0x0000000000000006
	cpu4: 0x0000000000000006
	cpu5: 0x0000000000000006
	cpu6: 0x0000000000000006
	cpu7: 0x0000000000000006

	after

	cpu0: 0x0000000000000000
	cpu1: 0x0000000000000006
	cpu2: 0x0000000000000006
	cpu3: 0x0000000000000006
	cpu4: 0x0000000000000006
	cpu5: 0x0000000000000006
	cpu6: 0x0000000000000006
	cpu7: 0x0000000000000006

Resulting in inconsistent energy policy settings across CPUs.

This register is set via init_intel() at bootup. During resume,
the secondary CPUs are brought online again and init_intel() is
callled which re-initializes the register. The boot CPU however
never reinitializes the register.

Add a syscore callback to reinitialize the register for the boot CPU.

Signed-off-by: default avatarLaura Abbott <labbott@fedoraproject.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.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/1437428878-4105-1-git-send-email-labbott@fedoraproject.org


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 9d634c41
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