On 10.12.19 09:44, Baoquan He wrote:
In commit 357b4da50a62 ("x86: respect memory size limiting via mem=
parameter") a global varialbe global max_mem_size is added to store
the value parsed from 'mem= ', then checked when memory region is
added. This truly stops those DIMM from being added into system memory
during boot-time.
However, it also limits the later memory hotplug functionality. Any
memory board can't be hot added any more if its region is beyond the
max_mem_size. System will print error like below:
[ 216.387164] acpi PNP0C80:02: add_memory failed
[ 216.389301] acpi PNP0C80:02: acpi_memory_enable_device() error
[ 216.392187] acpi PNP0C80:02: Enumeration failure
From document of 'mem= ' parameter, it should be a restriction during
boot, but not impact the system memory adding/removing after booting.
mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
...
So fix it by also checking if it's during boot-time when restrict memory
adding. Otherwise, skip the restriction.
Fixes: 357b4da50a62 ("x86: respect memory size limiting via mem= parameter")
Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
Juergen
