Commits on Jun 13, 2024

1. x86/tsc: Make cur->adjusted values in package#1 to be the same …

   zhaoxin inclusion
   category: bugfix
   CVE: NA
   
   -----------------
   
   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.
   
   Signed-off-by: leoliu-oc <[email protected]>

   

   leoliu-oc committed Jun 13, 2024
   Configuration menu

   • View commit details
   • Copy full SHA for 3425874
   • Browse repository at this point

   Copy the full SHA

   3425874 View commit details

   Browse the repository at this point in the history