﻿id	summary	reporter	owner	description	type	status	component	version	resolution	keywords	cc	guest	host
19903	VBoxService CPU hotplug brings always cpu1 online regardless of plugged CPU => fixed in SVN/next maintenance	musteresel		"The code to bring a newly plugged CPU online is seriously wrong, textual description of what is done there:

 - Lists all files under /sys/devices/system/cpu
 - Iterates over these, one after the other
 - If current file name starts with ""cpu"" but is not ""cpu0"" nor ""cpuidle"", then
 - Tries to open /sys/devices/system/cpu/FILENAME/online and write 1 to it
 - If that succeeds (for ONE single file), calls it a day and returns.

Actual code is here: https://www.virtualbox.org/browser/vbox/trunk/src/VBox/Additions/common/VBoxService/VBoxServiceCpuHotPlug.cpp#L449

Assuming (?) that the directory listing is sorted by name, this will always put cpu1 (and only that!) online.

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Stumbled over this while trying to find out why my CPU (cpu2 ... cpu1 comes before that in the directory listing) isn't online prior to getting it back offline (https://www.virtualbox.org/ticket/19902)"	defect	closed	guest additions	VirtualBox 6.1.6	fixed	hotplug		Linux	Linux
