Process hangs for an hour on init

zacaway commented 2 years ago

Found this as it affects minio, which uses cpuid, but it is easily reproducible just using the example program. Running that example program on my machine hangs for about an hour, then the program continues normally. Seems to be due to this for-loop which loops about 4 billion times on my machine.

Here is my CPU spec (from /proc/cpuinfo) if it helps:

processor   : 0
vendor_id   : AuthenticAMD
cpu family  : 25
model       : 80
model name  : AMD Ryzen 7 5700G with Radeon Graphics
stepping    : 0
microcode   : 0xa50000c
cpu MHz     : 3792.874
cache size  : 512 KB
physical id : 0
siblings    : 4
core id     : 0
cpu cores   : 4
apicid      : 0
initial apicid  : 0
fpu     : yes
fpu_exception   : yes
cpuid level : 13
wp      : yes
flags       : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm rep_good nopl cpuid extd_apicid tsc_known_freq pni pclmulqdq ssse3 fma cx16 sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx f16c rdrand hypervisor lahf_lm cr8_legacy abm sse4a misalignsse 3dnowprefetch bpext ssbd ibrs ibpb stibp vmmcall fsgsbase bmi1 avx2 smep bmi2 erms invpcid rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves clzero xsaveerptr arat umip pku ospke vaes vpclmulqdq rdpid
bugs        : sysret_ss_attrs null_seg spectre_v1 spectre_v2 spec_store_bypass
bogomips    : 7585.74
TLB size    : 2560 4K pages
clflush size    : 64
cache_alignment : 64
address sizes   : 48 bits physical, 48 bits virtual
power management:

processor   : 1
vendor_id   : AuthenticAMD
cpu family  : 25
model       : 80
model name  : AMD Ryzen 7 5700G with Radeon Graphics
stepping    : 0
microcode   : 0xa50000c
cpu MHz     : 3792.874
cache size  : 512 KB
physical id : 0
siblings    : 4
core id     : 2
cpu cores   : 4
apicid      : 2
initial apicid  : 2
fpu     : yes
fpu_exception   : yes
cpuid level : 13
wp      : yes
flags       : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm rep_good nopl cpuid extd_apicid tsc_known_freq pni pclmulqdq ssse3 fma cx16 sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx f16c rdrand hypervisor lahf_lm cr8_legacy abm sse4a misalignsse 3dnowprefetch bpext ssbd ibrs ibpb stibp vmmcall fsgsbase bmi1 avx2 smep bmi2 erms invpcid rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves clzero xsaveerptr arat umip pku ospke vaes vpclmulqdq rdpid
bugs        : sysret_ss_attrs null_seg spectre_v1 spectre_v2 spec_store_bypass
bogomips    : 7608.95
TLB size    : 2560 4K pages
clflush size    : 64
cache_alignment : 64
address sizes   : 48 bits physical, 48 bits virtual
power management:

processor   : 2
vendor_id   : AuthenticAMD
cpu family  : 25
model       : 80
model name  : AMD Ryzen 7 5700G with Radeon Graphics
stepping    : 0
microcode   : 0xa50000c
cpu MHz     : 3792.874
cache size  : 512 KB
physical id : 0
siblings    : 4
core id     : 4
cpu cores   : 4
apicid      : 4
initial apicid  : 4
fpu     : yes
fpu_exception   : yes
cpuid level : 13
wp      : yes
flags       : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm rep_good nopl cpuid extd_apicid tsc_known_freq pni pclmulqdq ssse3 fma cx16 sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx f16c rdrand hypervisor lahf_lm cr8_legacy abm sse4a misalignsse 3dnowprefetch bpext ssbd ibrs ibpb stibp vmmcall fsgsbase bmi1 avx2 smep bmi2 erms invpcid rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves clzero xsaveerptr arat umip pku ospke vaes vpclmulqdq rdpid
bugs        : sysret_ss_attrs null_seg spectre_v1 spectre_v2 spec_store_bypass
bogomips    : 7618.22
TLB size    : 2560 4K pages
clflush size    : 64
cache_alignment : 64
address sizes   : 48 bits physical, 48 bits virtual
power management:

processor   : 3
vendor_id   : AuthenticAMD
cpu family  : 25
model       : 80
model name  : AMD Ryzen 7 5700G with Radeon Graphics
stepping    : 0
microcode   : 0xa50000c
cpu MHz     : 3792.874
cache size  : 512 KB
physical id : 0
siblings    : 4
core id     : 6
cpu cores   : 4
apicid      : 6
initial apicid  : 6
fpu     : yes
fpu_exception   : yes
cpuid level : 13
wp      : yes
flags       : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm rep_good nopl cpuid extd_apicid tsc_known_freq pni pclmulqdq ssse3 fma cx16 sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx f16c rdrand hypervisor lahf_lm cr8_legacy abm sse4a misalignsse 3dnowprefetch bpext ssbd ibrs ibpb stibp vmmcall fsgsbase bmi1 avx2 smep bmi2 erms invpcid rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves clzero xsaveerptr arat umip pku ospke vaes vpclmulqdq rdpid
bugs        : sysret_ss_attrs null_seg spectre_v1 spectre_v2 spec_store_bypass
bogomips    : 7608.25
TLB size    : 2560 4K pages
clflush size    : 64
cache_alignment : 64
address sizes   : 48 bits physical, 48 bits virtual
power management: