Re: kern/60568: panic locking against myself (p->p_lock) in NFS from sysctl_vmproc

The following reply was made to PR kern/60568; it has been noted by GNATS.

From: "Greg A. Woods" <[email protected]>
To: Taylor R Campbell <[email protected]>
Cc: NetBSD GNATS <[email protected]>
Subject: Re: kern/60568: panic locking against myself (p->p_lock) in NFS from sysctl_vmproc
Date: Mon, 10 Aug 2026 19:27:21 -0700

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 At Tue, 11 Aug 2026 02:07:47 +0000, Taylor R Campbell <[email protected]> wrote:
 Subject: Re: kern/60568: panic locking against myself (p->p_lock) in NFS from sysctl_vmproc
 >
 > Sorry about that -- typo on my part (`pid != -1' should've been `pid
 > == -1' in that assertion), along with some other issues I saw on
 > review.  Try the attached one instead?
 
 No worries!  It'll have to wait until tomorrow though.
 
 > It's a bit tricky to provoke the path you hit originally: I think the
 > vnode for a parent directory of cwd has to be recycled, causing the
 > nfs client to wait for network traffic to look it up again.
 >
 > I'm curious to know what you were doing that led to it?  Debuggers
 > like gdb are likely to use the affected sysctl but I'm not sure what
 > else.
 
 I'm basically just running "make regress" in my yajl project.
 
 I think it failed during the initial build a few times, i.e. just
 running the compiler, but the latest crash was during the run of the
 regression tests.
 
 I'm pretty sure the latest run was with "-fsanitizer=address" as well.
 
 I was initially just trying to figure out if UBSAN was finally working
 in -current, but so far as I can tell it is not, though ASAN seems to
 work (and did even back with gcc-9.3.0).  UBSAN compiled and linked
 binaries won't even print out their help message.  So far I've only had
 UBSAN work with Clang on FreeBSD and macOS (I haven't tried any linux in
 over a year).
 
 --
 					Greg A. Woods <[email protected]>
 
 Kelowna, BC     +1 250 762-7675           RoboHack <[email protected]>
 Planix, Inc. <[email protected]>     Avoncote Farms <[email protected]>
 
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