Messages in this thread | | | Subject | Re: [PATCH] kernel/hung_task: Add a whitelist and blacklist mechanism. | From | Tetsuo Handa <> | Date | Sat, 17 Apr 2021 23:44:40 +0900 |
| |
On 2021/04/17 23:13, zhouchuangao wrote: > The main purpose of this patch is to add a whitelist and blacklist > mechanism to the hung task thread.
We stopped using the term 'whitelist'/'blacklist' for new code in Linux kernel, and what you are proposing is something like 'ignorelist'/'fatallist'.
I think that matching based on comm name is poor, for comm name is subjected to impersonation by malicious user processes.
Moreover, speak of syzkaller testing, most of hang task reports are reaction to somebody else consuming too much CPU resources (e.g. printk() flooding, too many pending workqueue requests). Even if some process is in 'ignorelist', it is possible that some problem that should be reported is already happening. Even if some process is in 'fatallist', it is possible that the cause of hang is simply somebody else is consuming too much CPU.
By the way, I wish that khungtaskd can report recent top CPU consumers, for it is rare that the cause of hung is locking dependency problems / hardware problems.
| |