[BUG] Incorrect core ids for certain CPUs (if the core ids are discontinuous)

[suxpert]

It is certain that core id in /proc/cpuinfo can be discontinuous, since that is commonly reported:
see here and here for examples.
Perhaps that is because our CPUs were "downgraded" by blocking some cores.

On my computer, simple monitor show 15 cores ranging from 0 to 14 as following:

while in /proc/cpuinfo, I have:

$ grep 'core id' /proc/cpuinfo
core id         : 0
core id         : 1
core id         : 2
core id         : 3
core id         : 4
core id         : 5
core id         : 6
core id         : 8
core id         : 9
core id         : 10
core id         : 11
core id         : 12
core id         : 13
core id         : 14
core id         : 0
core id         : 1
core id         : 2
core id         : 3
core id         : 4
core id         : 5
core id         : 6
core id         : 8
core id         : 9
core id         : 10
core id         : 11
core id         : 12
core id         : 13
core id         : 14

where core id 7 does not exist, but were shown in simple monitor, with a temperature that never change.