DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 6.5-DEVELOPMENT #0: Thu Jul  2 06:02:54 UTC 2026     root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC  x86_64
cc 8.3 [DragonFly] Release/2019-02-22
 4    1 0xffffffff82600000     d000 df229x.ko
kern.df229x_status: guard: esize=0 -> 0, esize<0 -> 0, n=0 -> 0 (no trap)
df229x: prepared, fc=0xffffffff82607200 sizeof(fwdma_alloc_multi)=32 sizeof(fw_bulkxfer)=48 sizeof(fwdma_seg)=24
df229x/t3: FW_SSTBUF{tx: nchunk=1 npacket=1 psize=0x0} + FW_STSTREAM -> fwdev_allocbuf (fwdev.c:107-109) -> fwdma_malloc_multiseg(esize=(int)roundup2(0x0,4))
df229x/t3: firing -- baseline expectation: Fatal trap 17 (divide error) in fwdma_malloc_multiseg
df229x/t3: SSTBUF err=0
df229x/t3: STSTREAM returned err=22 (reached here -> NO divide-by-zero: the fix rejected the bufspec)
df229x/t1: FW_SSTBUF{tx: nchunk=1 npacket=1 psize=0x80000000} + FW_STSTREAM -> fwdev_allocbuf (fwdev.c:107-109) -> fwdma_malloc_multiseg(esize=(int)roundup2(0x80000000,4))
df229x/t1: firing -- baseline expectation: Fatal trap 17 (divide error) in fwdma_malloc_multiseg
df229x/t1: SSTBUF err=0
df229x/t1: STSTREAM returned err=22 (reached here -> NO divide-by-zero: the fix rejected the bufspec)
df2298b: SSTBUF{nchunk=1,npacket=0,psize=512} + STSTREAM -> err=22 d->it=0 (baseline equivalence: n==0 -> nseg==0, the same zero-length seg[] as the overflow variant)
df2298: int-overflow n=nchunk*npacket -> zero-length seg[] -> OOB seg[0] read -> controlled write test
df2298/a1: STSTREAM err=22 -- bufspec rejected, no zero-seg allocation (it=0 buf=0 bulkxfer=0)
df2298/a2: STSTREAM err=22 -- bufspec rejected, no zero-seg allocation (it=0 buf=0 bulkxfer=0)
df2298/a3: STSTREAM err=22 -- bufspec rejected, no zero-seg allocation (it=0 buf=0 bulkxfer=0)
df2298: giving up after 3 attempts (status has the result)
df229x: DF-2298 nchunk=npacket=0x10000: STSTREAM err=22 (rejected, no write)
df229x/regression: legit {4,8,2048}: STSTREAM=0 fw_write=0 -- normal use intact
df229x/guard: fwdma_malloc_multiseg(esize=0)=0 (esize=-4096)=0 (n=0)=0 -- no trap