Re: kern/54945 (nfs uvm_pagegetdirty panic)

[Rin Okuyama <rokuyama.rk%gmail.com@localhost>]

The following reply was made to PR kern/54945; it has been noted by GNATS.

From: Rin Okuyama <rokuyama.rk%gmail.com@localhost>
To: gnats-bugs%netbsd.org@localhost, ad%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
 netbsd-bugs%netbsd.org@localhost, prlw1%cam.ac.uk@localhost
Cc: 
Subject: Re: kern/54945 (nfs uvm_pagegetdirty panic)
Date: Fri, 21 Feb 2020 00:07:59 +0900

 I found that the test program in the previous message does not cause
 panic even with NFS on ibm4xx, if taking enough intervals manually
 between each steps in the program, i.e., write-wait-mmap-wait...
 
 This result maybe implies that panic occurred only on ibm4xx, and not
 amd64 nor armv6 just because of timing problem; ibm4xx is too slow to
 finish asynchronous NFS IO and mark that page clean before read from
 mmap'ed address.
 
 Here's UVMHIST for successful read from mmap'ed address:
 
      http://www.netbsd.org/~rin/uvmhist_20200220_success.txt
 
 Thoughts?
 
 Thanks,
 rin