Just encountered this error running the latest kernel on RISCV. [ 413.938823] ------------[ cut here ]------------ [ 413.938838] DMA-API: nvme 0000:05:00.0: device driver tries to free DMA memory it has not allocated [device address=0x00000000fc0bf000] [size=4096 bytes] [ 413.938881] WARNING: CPU: 0 PID: 220 at kernel/dma/debug.c:1010 check_unmap+0x4ee/0x5f8 [ 413.938885] Modules linked in: [ 413.938896] CPU: 0 PID: 220 Comm: btrfs-transacti Not tainted 5.6.2 #1 [ 413.938903] epc: ffffffe000093c32 ra : ffffffe000093c32 sp : ffffffe1f563b220 [ 413.938909] gp : ffffffe000a414b0 tp : ffffffe1f61dca00 t0 : ffffffe000a61fc0 [ 413.938914] t1 : 0000000000000001 t2 : 2065657266206f74 s0 : ffffffe1f563b270 [ 413.938919] s1 : 00000000fc0bf000 a0 : 000000000000008d a1 : 0000000000000000 [ 413.938925] a2 : 0000000000000001 a3 : 0000000000000000 a4 : ffffffe000ad4218 [ 413.938931] a5 : fffffffffffffff8 a6 : ffffffe000a51c78 a7 : 000000000000029a [ 413.938936] s2 : ffffffe1f563b280 s3 : ffffffe000aa2bb8 s4 : 0000000200000022 [ 413.938942] s5 : ffffffe000a40e84 s6 : ffffffe000a41b78 s7 : 6db6db6db6db6db7 [ 413.938948] s8 : ffffffe000a42418 s9 : ffffffe1f563b280 s10: ffffffe1b7bbf000 [ 413.938953] s11: 0000000000000000 t3 : 0000000000000000 t4 : 6168207469207972 [ 413.938957] t5 : 6c6120746f6e2073 t6 : ffffffe000a61fbd [ 413.938963] status: 0000000200000120 badaddr: 0000000000000000 cause: 0000000000000003 [ 413.938967] ---[ end trace e6da251bf9c89f90 ]--- [ 442.600678] nvme nvme0: controller is down; will reset: CSTS=0x3, PCI_STATUS=0x10
Resolved by change to the PCIe bus.