Unverified Commit 28b1e846 authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
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!3175 [OLK-6.6] x86/tsc: Make cur->adjusted values in package#1 to be the same 

Merge Pull Request from: @leoliu-oc 
 
When resume from S4 on Zhaoxin 2 packages platform that support
X86_FEATURE_TSC_ADJUST, the following warning messages appear:

[  327.445302] [Firmware Bug]: TSC ADJUST differs: CPU15 45960750 --> 78394770. Restoring
[  329.209120] [Firmware Bug]: TSC ADJUST differs: CPU14 45960750 --> 78394770. Restoring
[  329.209128] [Firmware Bug]: TSC ADJUST differs: CPU13 45960750 --> 78394770. Restoring
[  329.209138] [Firmware Bug]: TSC ADJUST differs: CPU12 45960750 --> 78394770. Restoring
[  329.209151] [Firmware Bug]: TSC ADJUST differs: CPU11 45960750 --> 78394770. Restoring
[  329.209160] [Firmware Bug]: TSC ADJUST differs: CPU10 45960750 --> 78394770. Restoring
[  329.209169] [Firmware Bug]: TSC ADJUST differs: CPU9 45960750 --> 78394770. Restoring

The reason is:

Step 1: Bring up.
	TSC is sync after bring up with following settings:
				MSR 0x3b	cur->adjusted
	Package#0 CPU 0-7	  0		  0
	Package#1 first CPU	  value1	  value1
	Package#1 non-first CPU	  value1	  value1

Step 2: Suspend to S4.
	Settings in Step 1 are not changed in this Step.

Step 3: Bring up caused by S4 wake up event.
	TSC is sync when bring up with following settings:
				MSR 0x3b	cur->adjusted
	Package#0 CPU 0-7	  0		  0
	Package#1 first CPU	  value2	  value2
	Package#1 non-first CPU	  value2	  value2

Step 4: Resume from S4.
	When resuming from S4, Current TSC synchronous mechanism
	cause following settings:
				MSR 0x3b	cur->adjusted
	Package#0 CPU 0-7	  0		  0
	Package#1 first CPU	  value2	  value2
	Package#1 non-first CPU	  value2	  value1

In these Steps, value1 != 0 and value2 != value1.

In Step4, as function tsc_store_and_check_tsc_adjust() do, when the value
of MSR 0x3b on the non-first online CPU in package#1 is equal to the value
of cur->adjusted on the first online CPU in the same package, the
cur->adjusted value on this non-first online CPU will hold the old value1.
This cause function tsc_verify_tsc_adjust() set the value of MSR 0x3b on
the non-first online CPUs in the package#1 to the old value1 and print the
beginning warning messages.

Fix it by setting cur->adjusted value on the non-first online CPU in a
package to the value of MSR 0x3b on the same CPU when they are not equal.


### Issue
https://gitee.com/openeuler/kernel/issues/I8WZ1E

### Test
Pass: The firmware bug log disappears, which is expected 
 
Link:https://gitee.com/openeuler/kernel/pulls/3175

 

Reviewed-by: default avatarJason Zeng <jason.zeng@intel.com>
Reviewed-by: default avatarAichun Shi <aichun.shi@intel.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parents 72b481ee 1b205dc9

arch/x86/kernel/tsc_sync.c

+5 −0
Original line number Diff line number Diff line
@@ -232,6 +232,11 @@ bool tsc_store_and_check_tsc_adjust(bool bootcpu) 
	if (bootval != ref->adjusted) {

		cur->adjusted = ref->adjusted;

		wrmsrl(MSR_IA32_TSC_ADJUST, ref->adjusted);

	} else if (cur->adjusted != bootval) {

		if (boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR ||

			boot_cpu_data.x86_vendor == X86_VENDOR_ZHAOXIN) {

			cur->adjusted = bootval;

		}

	}

	/*

	 * We have the TSCs forced to be in sync on this package. Skip sync