When writing to a hard disc accessed via USB3 I get a panic and a kernel coredump. I've recompiled my GENERIC Kernel with debug; uname -a says

FreeBSD mordax 12.3-RELEASE-p5 FreeBSD 12.3-RELEASE-p5 GENERIC  amd64

dmesg says:

#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARN_ON(!mutex_is_locked(&dev->struct_mutex))
                        
WARN_ON(!mutex_is_locked(&fbc->lock))
   
WARN_ON(!mutex_is_locked(&fbc->lock))WARN_ON(!mutex_is_locked(&fbc->lock))WARN_ON(!mutex_is_locked(&fbc->lock))
panic: pctrie_remove: impossible to locate the key
cpuid = 3
time = 1649598985
KDB: stack backtrace:
#0 0xffffffff80c2d4a5 at kdb_backtrace+0x65
#1 0xffffffff80be163b at vpanic+0x17b
#2 0xffffffff80be14b3 at panic+0x43
#3 0xffffffff80c3152e at pctrie_remove+0x1ae
#4 0xffffffff80cafa03 at reassignbuf+0x73
#5 0xffffffff80c90639 at bdirty+0x39
#6 0xffffffff80c8f80d at brelse+0x10d
#7 0xffffffff80c920e0 at bufdone+0x2d0
#8 0xffffffff80b2db2b at g_io_deliver+0x1eb
#9 0xffffffff80b2db2b at g_io_deliver+0x1eb
#10 0xffffffff80b2aab2 at g_disk_done+0x102
#11 0xffffffff80c2665e at bioq_flush+0x7e
#12 0xffffffff80382698 at cam_iosched_flush+0x18
#13 0xffffffff803bcdab at dadone+0x15b
#14 0xffffffff8038cd77 at xpt_done_process+0x407
#15 0xffffffff8038f035 at xpt_done_td+0xf5
#16 0xffffffff80ba2a0e at fork_exit+0x7e
#17 0xffffffff810d61de at fork_trampoline+0xe
Uptime: 17h33m36s
Dumping 837 out of 8023 MB:..2%..12%..22%..31%..41%..52%..62%..71%..81%..92%---<<BOOT>>---

issueing
kgdb /usr/lib/debug/boot/kernel/kernel.debug /var/crash/vmcore.0

I get:

GNU gdb (GDB) 11.2 [GDB v11.2 for FreeBSD]
Copyright (C) 2022 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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Type "show copying" and "show warranty" for details.
This GDB was configured as "x86_64-portbld-freebsd12.2".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
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For help, type "help".
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Reading symbols from /usr/lib/debug/boot/kernel/kernel.debug...

Unread portion of the kernel message buffer:
(da0:umass-sim0:0:0:0): READ(10). CDB: 28 00 04 f2 84 e8 00 00 80 00 
(da0:umass-sim0:0:0:0): CAM status: SCSI Status Error
(da0:umass-sim0:0:0:0): SCSI status: Check Condition
(da0:umass-sim0:0:0:0): SCSI sense: MEDIUM ERROR asc:11,0 (Unrecovered read error)
(da0:umass-sim0:0:0:0): Error 5, Unretryable error
g_vfs_done():da0p1[READ(offset=42497376256, length=131072)]error = 5
g_vfs_done():da0p1[READ(offset=42497507328, length=131072)]error = 5
g_vfs_done():da0p1[READ(offset=42497638400, length=131072)]error = 5
g_vfs_done():da0p1[WRITE(offset=964266131456, length=131072)]error = 5
g_vfs_done():da0p1[WRITE(offset=964266262528, length=131072)]error = 5
g_vfs_done():da0p1[READ(offset=7614693376, length=131072)]error = 5
g_vfs_done():da0p1[READ(offset=7614824448, length=131072)]error = 5
g_vfs_done():da0p1[WRITE(offset=964266393600, length=131072)]error = 5
g_vfs_done():da0p1[WRITE(offset=964266524672, length=131072)]error = 5
g_vfs_done():da0p1[READ(offset=7614955520, length=131072)]error = 5
g_vfs_done():da0p1[READ(offset=7615086592, length=131072)]error = 5
g_vfs_done():da0p1[WRITE(offset=26880512, length=3072)]error = 5
WARNING !drm_modeset_is_locked(&crtc->mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:577
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff828536bd at drm_atomic_helper_check_modeset+0xcd
#2 0xffffffff8279d1cf at intel_atomic_check+0x1f
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARNING !drm_modeset_is_locked(&crtc->mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:577
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff828536bd at drm_atomic_helper_check_modeset+0xcd
#2 0xffffffff8279d1cf at intel_atomic_check+0x1f
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARNING !drm_modeset_is_locked(&crtc->mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:577
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff828536bd at drm_atomic_helper_check_modeset+0xcd
#2 0xffffffff8279d1cf at intel_atomic_check+0x1f
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARNING !drm_modeset_is_locked(&dev->mode_config.connection_mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:622
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff82853840 at drm_atomic_helper_check_modeset+0x250
#2 0xffffffff8279d1cf at intel_atomic_check+0x1f
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARNING !drm_modeset_is_locked(&plane->mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:821
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff82854917 at drm_atomic_helper_check_planes+0xa7
#2 0xffffffff8279deec at intel_atomic_check+0xd3c
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARNING !drm_modeset_is_locked(&plane->mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:821
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff82854917 at drm_atomic_helper_check_planes+0xa7
#2 0xffffffff8279deec at intel_atomic_check+0xd3c
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARNING !drm_modeset_is_locked(&plane->mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:821
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff82854917 at drm_atomic_helper_check_planes+0xa7
#2 0xffffffff8279deec at intel_atomic_check+0xd3c
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARNING !drm_modeset_is_locked(&plane->mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:821
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff82854917 at drm_atomic_helper_check_planes+0xa7
#2 0xffffffff8279deec at intel_atomic_check+0xd3c
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARNING !drm_modeset_is_locked(&plane->mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:821
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff82854917 at drm_atomic_helper_check_planes+0xa7
#2 0xffffffff8279deec at intel_atomic_check+0xd3c
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARNING !drm_modeset_is_locked(&plane->mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:821
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff82854917 at drm_atomic_helper_check_planes+0xa7
#2 0xffffffff8279deec at intel_atomic_check+0xd3c
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARNING !drm_modeset_is_locked(&plane->mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:821
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff82854917 at drm_atomic_helper_check_planes+0xa7
#2 0xffffffff8279deec at intel_atomic_check+0xd3c
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARNING !drm_modeset_is_locked(&plane->mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:821
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff82854917 at drm_atomic_helper_check_planes+0xa7
#2 0xffffffff8279deec at intel_atomic_check+0xd3c
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
WARNING !drm_modeset_is_locked(&plane->mutex) failed at /wrkdirs/usr/ports/graphics/drm-fbsd12.0-kmod/work/kms-drm-8843e1fc5/drivers/gpu/drm/drm_atomic_helper.c:821
#0 0xffffffff80e81f43 at linux_dump_stack+0x23
#1 0xffffffff82854917 at drm_atomic_helper_check_planes+0xa7
#2 0xffffffff8279deec at intel_atomic_check+0xd3c
#3 0xffffffff828516bb at drm_atomic_check_only+0x2ab
#4 0xffffffff82851a63 at drm_atomic_commit+0x13
#5 0xffffffff8287da38 at restore_fbdev_mode_atomic+0x1c8
#6 0xffffffff82879d5a at drm_fb_helper_restore_fbdev_mode_unlocked+0x7a
#7 0xffffffff8289f717 at vt_kms_postswitch+0x127
#8 0xffffffff80a4b79a at vt_window_switch+0x13a
#9 0xffffffff80a4880f at vtterm_cngrab+0x1f
#10 0xffffffff80b809c6 at cngrab+0x16
#11 0xffffffff80be15a5 at vpanic+0xe5
#12 0xffffffff80be14b3 at panic+0x43
#13 0xffffffff80c3152e at pctrie_remove+0x1ae
#14 0xffffffff80cafa03 at reassignbuf+0x73
#15 0xffffffff80c90639 at bdirty+0x39
#16 0xffffffff80c8f80d at brelse+0x10d
#17 0xffffffff80c920e0 at bufdone+0x2d0
<4>WARN_ON(!mutex_is_locked(&dev->struct_mutex))
                        
<4>WARN_ON(!mutex_is_locked(&fbc->lock))
   
<4>WARN_ON(!mutex_is_locked(&fbc->lock))WARN_ON(!mutex_is_locked(&fbc->lock))WARN_ON(!mutex_is_locked(&fbc->lock))
panic: pctrie_remove: impossible to locate the key
cpuid = 3
time = 1649598985
KDB: stack backtrace:
#0 0xffffffff80c2d4a5 at kdb_backtrace+0x65
#1 0xffffffff80be163b at vpanic+0x17b
#2 0xffffffff80be14b3 at panic+0x43
#3 0xffffffff80c3152e at pctrie_remove+0x1ae
#4 0xffffffff80cafa03 at reassignbuf+0x73
#5 0xffffffff80c90639 at bdirty+0x39
#6 0xffffffff80c8f80d at brelse+0x10d
#7 0xffffffff80c920e0 at bufdone+0x2d0
#8 0xffffffff80b2db2b at g_io_deliver+0x1eb
#9 0xffffffff80b2db2b at g_io_deliver+0x1eb
#10 0xffffffff80b2aab2 at g_disk_done+0x102
#11 0xffffffff80c2665e at bioq_flush+0x7e
#12 0xffffffff80382698 at cam_iosched_flush+0x18
#13 0xffffffff803bcdab at dadone+0x15b
#14 0xffffffff8038cd77 at xpt_done_process+0x407
#15 0xffffffff8038f035 at xpt_done_td+0xf5
#16 0xffffffff80ba2a0e at fork_exit+0x7e
#17 0xffffffff810d61de at fork_trampoline+0xe
Uptime: 17h33m36s
Dumping 837 out of 8023 MB:..2%..12%..22%..31%..41%..52%..62%..71%..81%..92%

__curthread () at /usr/src/sys/amd64/include/pcpu_aux.h:55
55		__asm("movq %%gs:%P1,%0" : "=r" (td) : "n" (offsetof(struct pcpu,
(kgdb) bt
#0  __curthread () at /usr/src/sys/amd64/include/pcpu_aux.h:55
#1  doadump (textdump=<optimized out>) at /usr/src/sys/kern/kern_shutdown.c:371
#2  0xffffffff80be1255 in kern_reboot (howto=260) at /usr/src/sys/kern/kern_shutdown.c:452
#3  0xffffffff80be1693 in vpanic (fmt=<optimized out>, ap=<optimized out>) at /usr/src/sys/kern/kern_shutdown.c:881
#4  0xffffffff80be14b3 in panic (fmt=<unavailable>) at /usr/src/sys/kern/kern_shutdown.c:808
#5  0xffffffff80c3152e in pctrie_remove (ptree=<optimized out>, index=<unavailable>, freefn=<unavailable>) at /usr/src/sys/kern/subr_pctrie.c:621
#6  0xffffffff80cafa03 in BUF_PCTRIE_REMOVE (ptree=<unavailable>, key=<optimized out>) at /usr/src/sys/kern/vfs_subr.c:441
#7  buf_vlist_remove (bp=0xfffffe0001539420) at /usr/src/sys/kern/vfs_subr.c:2104
#8  reassignbuf (bp=0xfffffe0001539420) at /usr/src/sys/kern/vfs_subr.c:2543
#9  0xffffffff80c90639 in bdirty (bp=0xfffffe0001539420) at /usr/src/sys/kern/vfs_bio.c:2465
#10 0xffffffff80c8f80d in brelse (bp=0xfffffe0001539420) at /usr/src/sys/kern/vfs_bio.c:2658
#11 0xffffffff80c920e0 in bufdone (bp=0xfffffe0001539420) at /usr/src/sys/kern/vfs_bio.c:4458
#12 0xffffffff80b2db2b in g_io_deliver (bp=0xfffff801aabe8468, error=<optimized out>) at /usr/src/sys/geom/geom_io.c:740
#13 0xffffffff80b2db2b in g_io_deliver (bp=0xfffff801aae8ad38, error=<optimized out>) at /usr/src/sys/geom/geom_io.c:740
#14 0xffffffff80b2aab2 in g_disk_done (bp=0xfffff802024eb178) at /usr/src/sys/geom/geom_disk.c:261
#15 0xffffffff80c2665e in bioq_flush (head=0xfffff8000394db80, stp=0x0, error=5) at /usr/src/sys/kern/subr_disk.c:186
#16 0xffffffff80382698 in cam_iosched_flush (isc=0xfffff8000394db80, stp=0x0, err=5) at /usr/src/sys/cam/cam_iosched.c:1183
#17 0xffffffff803bcdab in dadone (periph=0xfffff800047e2800, done_ccb=0xfffff8011cdb6000) at /usr/src/sys/cam/scsi/scsi_da.c:4483
#18 0xffffffff8038cd77 in xpt_done_process (ccb_h=0xfffff8011cdb6000) at /usr/src/sys/cam/cam_xpt.c:5517
#19 0xffffffff8038f035 in xpt_done_td (arg=0xffffffff81bc8180 <cam_doneqs>) at /usr/src/sys/cam/cam_xpt.c:5544
#20 0xffffffff80ba2a0e in fork_exit (callout=0xffffffff8038ef40 <xpt_done_td>, arg=0xffffffff81bc8180 <cam_doneqs>, frame=0xfffffe0000438b00) at /usr/src/sys/kern/kern_fork.c:1080
#21 <signal handler called>
(kgdb) 

Maybe the disc has some hardware problems, though panic() is not the expected behaviour...

Luciano.