port-arm/54199: arm bus_dmamap_sync assertion failure

[thorpej%me.com@localhost]

>Number:         54199
>Category:       port-arm
>Synopsis:       arm bus_dmamap_sync assertion failure
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-arm-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun May 12 21:30:00 +0000 2019
>Originator:     Jason Thorpe
>Release:        8.99.37
>Organization:
Jason's messy garage of hackery
>Environment:
NetBSD opi-zero-plus 8.99.37 NetBSD 8.99.37 (GENERIC64) #3: Fri Apr 19 22:30:17 PDT 2019  thorpej@BigMac.local:/Volumes/Data0/Users/thorpej/hack/NetBSD/current/netbsd-src/sys/arch/evbarm/compile/GENERIC64 evbarm
>Description:
System was copying a large amount of data (comprised mostly of small files) from one USB-attached SSD to another.  "tar" command output was being relayed over an ssh session.  At some point, the kernel panic'd:

[ 1735156.504667] panic: kernel diagnostic assertion "offset < map->dm_mapsize" failed: file "../../../../arch/arm/arm32/bus_dma.c", line 1051 offset 0 mapsize 0
[ 1735156.504667] cpu0: Begin traceback...
[ 1735156.504667] trace fp ffffffc02c8bf020
[ 1735156.504667] fp ffffffc02c8bf040 vpanic() at ffffffc00047a330 netbsd:vpanic+0x198
[ 1735156.504667] fp ffffffc02c8bf0a0 kern_assert() at ffffffc0005b28a4 netbsd:kern_assert+0x5c
[ 1735156.504667] fp ffffffc02c8bf130 _bus_dmamap_sync() at ffffffc00005edb4 netbsd:_bus_dmamap_sync+0x1fc
[ 1735156.504667] fp ffffffc02c8bf1a0 sunxi_emac_intr() at ffffffc00003b974 netbsd:sunxi_emac_intr+0x2ec
[ 1735156.504667] fp ffffffc02c8bf210 gic_fdt_intr() at ffffffc00004ecdc netbsd:gic_fdt_intr+0x1c
[ 1735156.504667] fp ffffffc02c8bf230 pic_dispatch() at ffffffc000002884 netbsd:pic_dispatch+0x104
[ 1735156.504667] fp ffffffc02c8bf260 armgic_irq_handler() at ffffffc00000502c netbsd:armgic_irq_handler+0xcc
[ 1735156.504667] fp ffffffc02c8bf2d0 interrupt() at ffffffc000070ecc netbsd:interrupt+0x2c
[ 1735156.504667] tf ffffffc02c8bf2f0 el1_trap() at ffffffc00006ef8c netbsd:el1_trap
[ 1735156.504667] ---- trapframe 0xffffffc02c8bf2f0 (304 bytes) ----
[ 1735156.504667] pc=ffffffc00042e608,   spsr=0000000020000005
[ 1735156.504667] esr=0000000096000007,    far=ffffffc02b43a000
[ 1735156.504667] x0=0000000000000000,     x1=ffffffc000a28300
[ 1735156.504667] x2=ffff00005f354ba0,     x3=0000000000000000
[ 1735156.504667] x4=ffff00005b8acf08,     x5=0000000000000000
[ 1735156.504667] x6=0000000000000006,     x7=0000000000001802
[ 1735156.504667] x8=0000000000000004,     x9=0000000000000006
[ 1735156.504667] x10=0000000000000040,    x11=000000000000003f
[ 1735156.504667] x12=ffffffff00b22fd8,    x13=ffffffff00b22fd8
[ 1735156.504667] x14=0000000000000000,    x15=ffffffc02c8bf620
[ 1735156.504667] x16=000000020012fb98,    x17=0000f562e0618434
[ 1735156.504667] x18=0000f562e06e0e28,    x19=0000000000000080
[ 1735156.504667] x20=ffffffc000d230c8,    x21=ffff00005e610100
[ 1735156.504667] x22=ffffffc0006d45f8,    x23=ffffffc00070a030
[ 1735156.504667] x24=0000000000000000,    x25=ffffffc0006c2000
[ 1735156.504667] x26=0000000000000000,    x27=0000000000000000
[ 1735156.504667] x28=0000000000000015, fp=x29=ffffffc02c8bf420
[ 1735156.504667] lr=x30=ffffffc00042e608,     sp=ffffffc02c8bf420
[ 1735156.504667] ------------------------------------------------
[ 1735156.504667] fp ffffffc02c8bf420 mutex_enter() at ffffffc00042e608 netbsd:mutex_enter+0x128
[ 1735156.504667] fp ffffffc02c8bf4a0 genfs_getpages() at ffffffc0004ec2bc netbsd:genfs_getpages+0x594
[ 1735156.504667] fp ffffffc02c8bf620 VOP_GETPAGES() at ffffffc0004ea0dc netbsd:VOP_GETPAGES+0x44
[ 1735156.504667] fp ffffffc02c8bf6a0 ubc_fault() at ffffffc0003e653c netbsd:ubc_fault+0x16c
[ 1735156.504667] fp ffffffc02c8bf730 uvm_fault_internal() at ffffffc0003e90e0 netbsd:uvm_fault_internal+0x470
[ 1735156.504667] fp ffffffc02c8bf940 data_abort_handler() at ffffffc000071960 netbsd:data_abort_handler+0xf0
[ 1735156.504667] tf ffffffc02c8bf9c0 el1_trap() at ffffffc00006ef8c netbsd:el1_trap
[ 1735156.504667] ---- trapframe 0xffffffc02c8bf9c0 (304 bytes) ----
[ 1735156.504667] pc=ffffffc00006e2e8,   spsr=0000000060000005
[ 1735156.504667] esr=0000000096000007,    far=ffffffc02b43a000
[ 1735156.504667] x0=ffffffc02b43a000,     x1=0000000200132450
[ 1735156.504667] x2=0000000000001e00,     x3=0000000000001e00
[ 1735156.504667] x4=00000000000000f0,     x5=0000000000000000
[ 1735156.504667] x6=ffffffc02b43a000,     x7=0000000000000002
[ 1735156.504667] x8=0000000000000000,     x9=0000000000000050
[ 1735156.504667] x10=0000000000000040,    x11=000000000000003f
[ 1735156.504667] x12=000003fffffffa40,    x13=000003fffffffa46
[ 1735156.504667] x14=0000000000000000,    x15=0000000200132c50
[ 1735156.504667] x16=000000020012fb98,    x17=0000f562e0618434
[ 1735156.504667] x18=0000f562e06e0e28,    x19=ffffffc02b43a000
[ 1735156.504667] x20=0000000200132450,    x21=ffffffc02c8bfdf0
[ 1735156.504667] x22=0000000000001e00,    x23=ffffffc00061d000
[ 1735156.504667] x24=ffffffc00073ee50,    x25=ffffffc00073ed98
[ 1735156.504667] x26=ffffffc02b43a000,    x27=ffff00005f396a10
[ 1735156.504667] x28=ffffffc000731c68, fp=x29=ffffffc02c8bfb70
[ 1735156.504667] lr=x30=ffffffc00006e260,     sp=ffffffc02c8bfaf0
[ 1735156.504667] ------------------------------------------------
[ 1735156.504667] fp ffffffc02c8bfb70 copyout() at ffffffc00006e2e8 netbsd:copyout+0xac
[ 1735156.504667] fp ffffffc02c8bfb80 copyout_vmspace() at ffffffc00046356c netbsd:copyout_vmspace+0x4c
[ 1735156.504667] fp ffffffc02c8bfbd0 uiomove() at ffffffc000463674 netbsd:uiomove+0xa4
[ 1735156.504667] fp ffffffc02c8bfc30 ubc_uiomove() at ffffffc0003e6d00 netbsd:ubc_uiomove+0x180
[ 1735156.504667] fp ffffffc02c8bfcb0 ffs_read() at ffffffc0003d32f0 netbsd:ffs_read+0x138
[ 1735156.504667] fp ffffffc02c8bfd00 VOP_READ() at ffffffc0004e8cf8 netbsd:VOP_READ+0x40
[ 1735156.504667] fp ffffffc02c8bfd50 vn_read() at ffffffc0004e0898 netbsd:vn_read+0xa0
[ 1735156.504667] fp ffffffc02c8bfda0 dofileread() at ffffffc000489f90 netbsd:dofileread+0x70
[ 1735156.504667] fp ffffffc02c8bfe20 syscall() at ffffffc000070964 netbsd:syscall+0x19c
[ 1735156.504667] tf ffffffc02c8bfed0 el0_trap() at ffffffc00006eff0 netbsd:el0_trap
[ 1735156.504667] ---- trapframe 0xffffffc02c8bfed0 (304 bytes) ----
[ 1735156.504667] pc=0000f562e0618438,   spsr=0000000080000000
[ 1735156.504667] esr=0000000056000003,    far=ffffffc02b8f0000
[ 1735156.504667] x0=0000000000000007,     x1=0000000200131a50
[ 1735156.504667] x2=0000000000002800,     x3=00000002001310c0
[ 1735156.504667] x4=0000000000000000,     x5=0000000000000000
[ 1735156.504667] x6=0000fffffffe9128,     x7=0000000000000003
[ 1735156.504667] x8=0000000000008000,     x9=0000000000000000
[ 1735156.504667] x10=0000000000000040,    x11=000000000000003f
[ 1735156.504667] x12=000003fffffffa40,    x13=000003fffffffa46
[ 1735156.504667] x14=0000000000000000,    x15=0000000200132c50
[ 1735156.504667] x16=000000020012fb98,    x17=0000f562e0618434
[ 1735156.504667] x18=0000f562e06e0e28,    x19=0000000000000007
[ 1735156.504667] x20=000000020012fd40,    x21=000000020013d900
[ 1735156.504667] x22=0000fffffffe9238,    x23=0000000000a80200
[ 1735156.504667] x24=0000000200131830,    x25=000000020013feec
[ 1735156.504667] x26=0000000200111360,    x27=0000fffffffe9234
[ 1735156.504667] x28=000000020013d900, fp=x29=0000000000000000
[ 1735156.504667] lr=x30=0000000200108484,     sp=0000fffffffe9050
[ 1735156.504667] ------------------------------------------------
[ 1735156.504667] cpu0: End traceback...

>How-To-Repeat:
Does not reproduce readily.
>Fix:
Under investigation.