On 3/25/21 5:26 AM, Miroslav Benes wrote:
On Thu, 25 Mar 2021, Dong Kai wrote:commit 15b2219facad ("kernel: freezer should treat PF_IO_WORKER like PF_KTHREAD for freezing") is to fix the freezeing issue of IO threads by making the freezer not send them fake signals. Here live patching consistency model call klp_send_signals to wake up all tasks by send fake signal to all non-kthread which only check the PF_KTHREAD flag, so it still send signal to io threads which may lead to freezeing issue of io threads.I suppose this could happen, but it will also affect the live patching transition if the io threads do not react to signals. Are you able to reproduce it easily? I mean, is there a testcase I could use to take a closer look?
If repro is only hypothetical at this point, perhaps we can artificially create it in selftests? And useful to verify the future change you mentioned in your other reply?
-- Joe
