kern/55238: panic: kernel diagnostic assertion "M_LEADINGSPACE(m) >= (m->m_pkthdr.len - m->m_len)" failed: file "/usr/src/sys/kern/uipc_mbuf.c", line 1684

[kardel%netbsd.org@localhost]

>Number:         55238
>Category:       kern
>Synopsis:       panic: kernel diagnostic assertion "M_LEADINGSPACE(m) >= (m->m_pkthdr.len - m->m_len)" failed: file "/usr/src/sys/kern/uipc_mbuf.c", line 1684
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed May 06 10:15:00 +0000 2020
>Originator:     kardel%netbsd.org@localhost
>Release:        NetBSD 9.99.60
>Organization:
	
>Environment:
	
	
System: NetBSD Toblerone 9.99.60 NetBSD 9.99.60 (XEN3_DOMU) #5: Tue May  5 18:25:19 CEST 2020 kardel@Toblerone:/usr/src/sys/arch/amd64/compile/obj/XEN3_DOM0 amd64
Architecture: x86_64
Machine: amd64
>Description:
	amd64 -current 9.99.60@20200505 panics during network write.

[ 258.0289860] panic: kernel diagnostic assertion "M_LEADINGSPACE(m) >= (m->m_pkthdr.len - m->m_len)" failed: file "/usr/src/sys/kern/uipc_mbuf.c", line 1684 
[ 258.0289860] cpu1: Begin traceback...
[ 258.0289860] vpanic() at netbsd:vpanic+0x146
[ 258.0289860] kern_assert() at netbsd:kern_assert+0x48
[ 258.0289860] m_defrag() at netbsd:m_defrag+0x408
[ 258.0289860] xennet_start() at netbsd:xennet_start+0xc7
[ 258.0289860] if_transmit() at netbsd:if_transmit+0x107
[ 258.0289860] ether_output() at netbsd:ether_output+0x42d
[ 258.0289860] ip_output() at netbsd:ip_output+0x1343
[ 258.0289860] tcp_output() at netbsd:tcp_output+0x199d
[ 258.0289860] tcp_send_wrapper() at netbsd:tcp_send_wrapper+0xa6
[ 258.0289860] sosend() at netbsd:sosend+0x7d8
[ 258.0289860] soo_write() at netbsd:soo_write+0x2c
[ 258.0289860] dofilewrite() at netbsd:dofilewrite+0x7a
[ 258.0289860] sys_write() at netbsd:sys_write+0x49
[ 258.0289860] syscall() at netbsd:syscall+0x9c
[ 258.0289860] --- syscall (number 4) ---
[ 258.0289860] 7080d124297a:
[ 258.0289860] cpu1: End traceback...
[ 258.0289860] rebooting...

>How-To-Repeat:
	run 9.99.60@20200505 with a java application serving web requests. Observe
	kernel diagnostic assertion "M_LEADINGSPACE(m) >= (m->m_pkthdr.len - m->m_len)" failed: file "/usr/src/sys/kern/uipc_mbuf.c", line 1684

>Fix:
	- not available -

>Unformatted: