Re: kern/59955: kernel diagnostic assertion "rw_lock_held(&map->lock)" failed: file "/home/riastradh/netbsd/11/src/sys/uvm/uvm_map.c", line 1704

["Chuck Silvers via gnats" <gnats-admin%NetBSD.org@localhost>]

The following reply was made to PR kern/59955; it has been noted by GNATS.

From: Chuck Silvers <chuq%chuq.com@localhost>
To: Taylor R Campbell <riastradh%NetBSD.org@localhost>
Cc: gnats-bugs%NetBSD.org@localhost, netbsd-bugs%NetBSD.org@localhost
Subject: Re: kern/59955: kernel diagnostic assertion
 "rw_lock_held(&map->lock)" failed: file
 "/home/riastradh/netbsd/11/src/sys/uvm/uvm_map.c", line 1704
Date: Sun, 1 Feb 2026 17:55:43 -0800

 On Sun, Feb 01, 2026 at 08:37:45PM +0000, Taylor R Campbell wrote:
 > Actually, just taking the read lock in mm_md_kernacc probably isn't
 > enough, because we really need the access to _remain_ allowed while we
 > do the uiomove in dev/mm.c.  Can we hold the map lock across uiomove?
 > Sounds unlikely.  Can we wire the pages with uvm_vslock or something
 > across the uvm_map_checkprot and uiomove?
 
 there is no need to call uvm_map_checkprot() here.  if uiomove() faults
 while trying to access an unmapped address within module_map, it will just
 fail with an error, which is what you'd want anyway.
 
 -Chuck