acpi: Provide mechanism to validate processors in the ACPI tables
[Problem]
When we set cpuid <-> nodeid mapping to be persistent, it will use the DSDT
As we know, the ACPI tables are just like user's input in that respect, and
we don't crash if user's input is unreasonable.
Such as, the mapping of the proc_id and pxm in some machine's ACPI table is
like this:
proc_id | pxm
--------------------
0 <-> 0
1 <-> 0
2 <-> 1
3 <-> 1
89 <-> 0
89 <-> 0
89 <-> 0
89 <-> 1
89 <-> 1
89 <-> 2
89 <-> 3
.....
We can't be sure which one is correct to the proc_id 89. We may map a wrong
node to a cpu. When pages are allocated, this may cause a kernal panic.
So, we should provide mechanisms to validate the ACPI tables, just like we
do validation to check user's input in web project.
The mechanism is that the processor objects which have the duplicate IDs
are not valid.
[Solution]
We add a validation function, like this:
foreach Processor in DSDT
proc_id = get_ACPI_Processor_number(Processor)
if (proc_id exists )
mark both of them as being unreasonable;
The function will record the unique or duplicate processor IDs.
The duplicate processor IDs such as 89 are regarded as the unreasonable IDs
which mean that the processor objects in question are not valid.
[ tglx: Add __init[data] annotations ]
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: mika.j.penttila@gmail.com
Cc: len.brown@intel.com
Cc: rafael@kernel.org
Cc: rjw@rjwysocki.net
Cc: yasu.isimatu@gmail.com
Cc: linux-mm@kvack.org
Cc: linux-acpi@vger.kernel.org
Cc: isimatu.yasuaki@jp.fujitsu.com
Cc: gongzhaogang@inspur.com
Cc: tj@kernel.org
Cc: izumi.taku@jp.fujitsu.com
Cc: cl@linux.com
Cc: chen.tang@easystack.cn
Cc: akpm@linux-foundation.org
Cc: kamezawa.hiroyu@jp.fujitsu.com
Cc: lenb@kernel.org
Link: http://lkml.kernel.org/r/1472114120-3281-7-git-send-email-douly.fnst@cn.fujitsu.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
1 file changed