kern/59959: nouveau triggers uvm assertion failure

["nia%pkgsrc.org@localhost via gnats" <gnats-admin%NetBSD.org@localhost>]

>Number:         59959
>Category:       kern
>Synopsis:       nouveau triggers uvm assertion failure
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Feb 02 17:25:00 +0000 2026
>Originator:     nia
>Release:        
>Organization:
The NouveauBSD Foundation
>Environment:
NetBSD siphon 11.99.4 NetBSD 11.99.4 (SIPHON) #1: Wed Jan  7 18:25:38 CET 2026  nia@siphon:/encrypt/obj/sys/arch/amd64/compile/SIPHON amd64
>Description:
System panicked: kernel diagnostic assertion "sdp->swd_npginuse >= nslots" failed: file "/encrypt/src/sys/uvm/uvm_swap.c", line 1805

Backtrace from time of crash is available.
crash> bt
vmx_insn_failinvalid() at 0
kern_reboot() at kern_reboot+0x5f
vpanic() at vpanic+0x193
kern_assert() at __x86_indirect_thunk_rax
uvm_swap_free() at uvm_swap_free+0x188
uao_dropswap_range() at uao_dropswap_range+0x262
uao_detach() at uao_detach+0x170
drm_gem_object_release() at drm_gem_object_release+0x18
nouveau_bo_del_ttm() at nouveau_bo_del_ttm+0x8d
ttm_bo_release_list() at ttm_bo_release_list+0xb8
ttm_bo_delayed_delete() at ttm_bo_delayed_delete+0x23b
ttm_bo_delayed_workqueue() at ttm_bo_delayed_workqueue+0x1a
linux_workqueue_thread() at linux_workqueue_thread+0x148
>How-To-Repeat:
IDK, it seemed quite random. Will see if it pops up again.
>Fix: