Re: [Intel AlderLake] Read&Write files to FAT32 or UFS partition cause data corrupt due to P-Core&E-Core

On 8/8/23 10:56, Tomoaki AOKI wrote:
> On Tue, 8 Aug 2023 17:02:32 +0300
> Konstantin Belousov <kostikbel@gmail.com> wrote:

  [ .. snip .. ]

>> The workaround is switched on automatically, when kernel detects 'small cores'
>> reported by CPUID.
> 
> If I read the code correctly, vm.pmap.pcid_invlpg_workaround
> (precicely, the corresponding variable) is set to non-zero when the
> workaround is enabled. Not sure it was detected correctly at the
> original reporter's environment, but forcibly setting the tunable to 1
> didn't reported to help sufficiently.
> Currently, only setting tunable vm.pmap.pcid_enabled to 0 could help.

I'm seeing similar stability problems on an N95-based device. This too 
is an Alderlake-N device with only E-cores although I'm running it with 
a compilation with CPUTYPE=tremont .. from an older, verbose start-up ..

PPIM 0: PA=0x4000000000, VA=0xffffffff82710000, size=0x1d5000, mode=0x1
pmap: large map 8 PML4 slots (4096 GB)
VT(efifb): resolution 800x600
Preloaded elf kernel "/boot/kernel.new/kernel" at 0xffffffff8234e000.
Preloaded boot_entropy_cache "/boot/entropy" at 0xffffffff82357d08.
Preloaded cpu_microcode "/boot/firmware/intel-ucode.bin" at 
0xffffffff82357d60.
Preloaded hostuuid "/etc/hostid" at 0xffffffff82357dc0.
Preloaded TSLOG data "TSLOG" at 0xffffffff82357e10.
CPU: Intel(R) N95 (1689.60-MHz K8-class CPU)
   Origin="GenuineIntel"  Id=0xb06e0  Family=0x6  Model=0xbe  Stepping=0
 
Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
 
Features2=0x7ffafbbf<SSE3,PCLMULQDQ,DTES64,MON,DS_CPL,VMX,EST,TM2,SSSE3,SDBG,FMA,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,x2APIC,MOVBE,POPCNT,TSCDLT,AESNI,XSAVE,OSXSAVE,AVX,F16C,RDRAND>
   AMD Features=0x2c100800<SYSCALL,NX,Page1GB,RDTSCP,LM>
   AMD Features2=0x121<LAHF,ABM,Prefetch>
   Structured Extended 
Features=0x239ca7eb<FSGSBASE,TSCADJ,BMI1,AVX2,FDPEXC,SMEP,BMI2,ERMS,INVPCID,NFPUSG,PQE,RDSEED,ADX,SMAP,CLFLUSHOPT,CLWB,PROCTRACE,SHA>
   Structured Extended 
Features2=0x98c007bc<UMIP,PKU,OSPKE,WAITPKG,GFNI,VAES,VPCLMULQDQ,RDPID,MOVDIRI,MOVDIR64B>
   Structured Extended 
Features3=0xfc184410<FSRM,MD_CLEAR,IBT,IBPB,STIBP,L1DFL,ARCH_CAP,CORE_CAP,SSBD>
   XSAVE Features=0xf<XSAVEOPT,XSAVEC,XINUSE,XSAVES>
   IA32_ARCH_CAPS=0x180fd6b<RDCL_NO,IBRS_ALL,SKIP_L1DFL_VME,MDS_NO,TAA_NO>
   VT-x: Basic Features=0x3da0500<SMM,INS/OUTS,TRUE>
         Pin-Based Controls=0xff<ExtINT,NMI,VNMI,PreTmr,PostIntr>
         Primary Processor 
Controls=0xfffbfffe<INTWIN,TSCOff,HLT,INVLPG,MWAIT,RDPMC,RDTSC,CR3-LD,CR3-ST,CR8-LD,CR8-ST,TPR,NMIWIN,MOV-DR,IO,IOmap,MTF,MSRmap,MONITOR,PAUSE>
         Secondary Processor 
Controls=0x75d7fff<APIC,EPT,DT,RDTSCP,x2APIC,VPID,WBINVD,UG,APIC-reg,VID,PAUSE-loop,RDRAND,INVPCID,VMFUNC,VMCS,XSAVES>
         Exit Controls=0x3da0500<PAT-LD,EFER-SV,PTMR-SV>
         Entry Controls=0x3da0500
         EPT Features=0x6f34141<XO,PW4,UC,WB,2M,1G,INVEPT,AD,single,all>
         VPID Features=0xf01<INVVPID,individual,single,all,single-globals>
   TSC: P-state invariant, performance statistics
64-Byte prefetching
L2 cache: 2048 kbytes, 16-way associative, 64 bytes/line
real memory  = 17179869184 (16384 MB)
Physical memory chunk(s):
0x0000000000010000 - 0x000000000009dfff, 581632 bytes (142 pages)
0x000000000009f000 - 0x000000000009ffff, 4096 bytes (1 pages)
0x0000000000100000 - 0x000000005fffffff, 1609564160 bytes (392960 pages)
0x0000000062401000 - 0x000000007264dfff, 270848000 bytes (66125 pages)
0x0000000075fff000 - 0x0000000075ffffff, 4096 bytes (1 pages)
0x0000000100001000 - 0x0000000462497fff, 14533881856 bytes (3548311 pages)
0x000000047fa00000 - 0x000000047fb68fff, 1478656 bytes (361 pages)
avail memory = 16363008000 (15604 MB)
CPU microcode: updated from 0xc to 0x10
MADT: Found CPU APIC ID 0 ACPI ID 0: enabled
SMP: Added CPU 0 (AP)
MADT: Found CPU APIC ID 2 ACPI ID 1: enabled
SMP: Added CPU 2 (AP)
MADT: Found CPU APIC ID 4 ACPI ID 2: enabled
SMP: Added CPU 4 (AP)
MADT: Found CPU APIC ID 6 ACPI ID 3: enabled
SMP: Added CPU 6 (AP)

On start-up, vm.pmap.pcid_invlpg_workaround=1 but seemingly random 
faults still occurred under load, for example, 'make buildworld'. 
Apparent misreads of source-files resulting in syntax errors were the 
most common symptom. Compilation reattempts (mostly) succeed.

Initially, I put this down to an inadequate power-supply but setting 
vm.pmap.pcid_enabled=0 seems to have stabilised it.

I guess there's another dragon in there .. :-(

	Michael