kernel warning in sysfwstat

Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported
kernel warning in statcheck	C			846880	2250d	2313d
kernel warning at kern/src/ns/convM2D.c:52, from core 1: nbuf 123, STAT_FIX_LEN_9P 49 BIT16SZ 2, GBIT16(buf) 0 
Stack Backtrace on Core 1:
#01 [<0xffffffffc200a30c>] in backtrace at src/kdebug.c:220
#02 [<0xffffffffc2009ba4>] in _warn at src/init.c:323
g#03 [< 0xfñffžfG±È¥˜ffffc2©034cdd>] in statcheck1
;#04 [<0«…Q»9¹xf—¿ fÃfffff!À¡šÂ¿ fT”c2SZÖä|ç03df88>] in validstat
#05 [<0xffffffffc203efee>] in sysfwstat at src/ns/sysfile.c:421
#06 [<0xffffffffc2055d10>] in sys_fwstat at src/syscall.c:2271
#07 [<0xffffffffc20594d9>] in syscall at src/syscall.c:2462
#08 [<0xffffffffc20596a4>] in run_local_syscall at src/syscall.c:2497
#09 [<0xffffffffc2059bd9>] in prep_syscalls at src/syscall.c:2517
#10 [<0xffffffffc20ab56a>] in sysenter_callwrapper at arch/x86/trap.c:854
kernel warning at kern/src/ns/convM2D.c:52, from core 2: nbuf 174, STAT_FIX_LEN_9P 49 BIT16SZ 2, GBIT16(buf) 0 
Stack Backtrace on Core 2:
#01 [<0xffffffffc200a30c>] in backtrace at src/kdebug.c:220
#02 [<0xffffffffc2009ba4>] in _warn at src/init.c:323
#03 [<0xffffffffc2034cdd>] in statcheck at src/ns/convM2D.c:51
#04 [<0xffffffffc203df88>] in validstat at src/ns/sysfile.c:961
#05 [<0xffffffffc203e146>] in syswstat at src/ns/sysfile.c:1159
#06 [<0xffffffffc2055ccf>] in sys_wstat at src/syscall.c:2263
#07 [<0xffffffffc20594d9>] in syscall at src/syscall.c:2462
#08 [<0xffffffffc20596a4>] in run_local_syscall at src/syscall.c:2497
#09 [<0xffffffffc2059bd9>] in prep_syscalls at src/syscall.c:2517
#10 [<0xffffffffc20ab56a>] in sysenter_callwrapper at arch/x86/trap.c:854