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Tx2 PCI-E DeviceDriver -- ioremap() succeeds but not all BAR space is accessible (kernel paging error)

Mar 04, 2024

My driver fails when I access the “upper” part of my virtualzed PCI-E space (Bar0 - 2MB MemWindow)

Driver is fine on x64 Ubuntu…something ARM specific?

Crash: handle kernel paging request at virtual address ffffff801020400c

Kernel: 4.9.253-tegra #1 SMP PREEMPT Mon Jul 26 12:19:28 PDT 2021 aarch64 aarch64 aarch64 GNU/Linux

Pertinent info below…appreciate any help…

Mike

map results/virtual addresses

0: Mapped global memory bar to ioremap retured ffffff8010200000 with size 2048 KB

_mil aim_mil0: Mapped IO memory bar to ffffff800b230000 with size 64 KB

[ 4.613946] aim_mil aim_mil0: Allocated shared memory to ffffff8014001000 with size 16384 KB

Crash Dump

4.654654] Unable to handle kernel paging request at virtual address ffffff801020400c

[ 4.664498] Mem abort info:

[ 4.675722] CPU2: shutdown

[ 4.676375] psci: CPU2 killed (polled 4 ms)

[ 4.744559] ESR = 0x96000061

[ 4.751733] Exception class = DABT (current EL), IL = 32 bits

[ 4.760126] SET = 0, FnV = 0

[ 4.764178] EA = 0, S1PTW = 0

[ 4.774531] Data abort info:

[ 4.777678] ISV = 0, ISS = 0x00000061

[ 4.781981] CM = 0, WnR = 1

[ 4.785428] swapper pgtable: 4k pages, 39-bit VAs, pgd = ffffff800a200000

[ 4.793023] [ffffff801020400c] *pgd=00000002371fe003, *pud=00000002371fe003, *pmd=0000000215e87003, *pte=00e8000040204707

[ 4.812628] Internal error: Oops: 96000061 [#1] PREEMPT SMP

[ 4.818221] Modules linked in: aim_mil(O+) overlay nvgpu ip_tables x_tables

[ 4.825296] CPU: 5 PID: 3154 Comm: systemd-udevd Tainted: G O 4.9.253-tegra #1

[ 4.833670] Hardware name: storm (DT)

[ 4.837345] task: ffffffc1a3086200 task.stack: ffffffc1a2274000

[ 4.843340] PC is at api_io_bm_rt_act_ini+0x7c/0x300 [aim_mil]

[ 4.849241] LR is at api_io_bm_rt_act_ini+0x208/0x300 [aim_mil]

[ 4.855179] pc : [] lr : [] pstate: 00400045

[ 4.862593] sp : ffffffc1a22777c0

[ 4.865915] x29: ffffffc1a22777c0 x28: ffffff800117ac98

[ 4.871026] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready

[ 4.876985] x27: ffffffc191300000 x26: ffffffc191310000

[ 4.882333] x25: ffffffc191312000 x24: 0000000020000000

[ 4.887680] x23: ffffffc191000000 x22: 0000000000000014

[ 4.893028] x21: 000000000000000c x20: 0000000000000000

[ 4.898375] x19: 0000000000000001 x18: 0000000000000001

[ 4.903722] x17: 0000000000000001 x16: 0000000000000007

[ 4.909069] x15: ffffffffffffffff x14: ffffff800a16edd8

[ 4.914417] x13: ffffff800a16ea17 x12: 0000000000000000

[ 4.919785] x11: 0000000000000006 x10: 00000000000003c2

[ 4.925135] x9 : 0000000000000000 x8 : ffffffc1b7052977

[ 4.930484] x7 : 0000000000000000 x6 : 0000000000000001

[ 4.935832] x5 : 0000000000000000 x4 : ffffffc1b5fecbe8

[ 4.941179] x3 : ffffffc1b5fecbe8 x2 : ffffff8010200000

[ 4.944449] bcpu-throttle-alert cooling device registered.

[ 4.945404] mcpu-throttle-alert cooling device registered.

[ 4.948151] gpu-throttle-alert cooling device registered.

[ 4.949267] gpio tegra-gpio wake18 for gpio=101(M:5)

[ 4.953080] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready

[ 4.973578] x1 : 000000000000400c x0 : ffffff801020400c

[ 4.980426] Process systemd-udevd (pid: 3154, stack limit = 0xffffffc1a2274000)

[ 4.987615] zram: Added device: zram0

[ 4.991420] Call trace:

[ 4.992698] zram: Added device: zram1

[ 4.997595] [] api_io_bm_rt_act_ini+0x7c/0x300 [aim_mil]

[ 5.004540] [] api_io_bm_ini+0xc4/0x190 [aim_mil]

[ 5.012515] [] api_sys_reset+0x738/0x868 [aim_mil]

[ 5.020599] [] api_main_init_and_reset+0x200/0x2b8 [aim_mil]

[ 5.029642] [] mil_hw_initialize_tsw+0x6c/0xa0 [aim_mil]

[ 5.038386] [] aim_pci_mil_init_tsw+0xb0/0x130 [aim_mil]

[ 5.047198] [] aim_pci_device_init_mil+0x80/0x90 [aim_mil]

[ 5.056002] [] aim_pci_probe+0x1f8/0x400 [aim_mil]

[ 5.064077] [] pci_device_probe+0xa4/0x140

[ 5.071426] [] driver_probe_device+0x298/0x448

lspci info

01:00.0 Memory controller: MyDevice Device 4100

Subsystem: MyDevice Device 0011

Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-

Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
Latency: 0

Interrupt: pin A routed to IRQ 382

Region 0: Memory at 40200000 (64-bit, non-prefetchable) [size=2M]

Region 2: Memory at 40100000 (64-bit, non-prefetchable) [size=64K]

Capabilities: [40] Power Management version 3

Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1+,D2+,D3hot+,D3cold-)

Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-

Capabilities: [48] MSI: Enable- Count=1/1 Maskable- 64bit+

Address: 0000000000000000 Data: 0000

Capabilities: [60] Express (v2) Endpoint, MSI 00

DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s <64ns, L1 unlimited

ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset- SlotPowerLimit 0.000W

DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-

RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+

MaxPayload 128 bytes, MaxReadReq 512 bytes

DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend-

LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s, Exit Latency L0s unlimited, L1 unlimited

ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-

LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk+

ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-

LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-

DevCap2: Completion Timeout: Range B, TimeoutDis-, LTR-, OBFF Not Supported

DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled

LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance- SpeedDis-

Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-

Compliance De-emphasis: -6dB

LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete-, EqualizationPhase1-

EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-

Capabilities: [100 v1] Device Serial Number 00-00-00-01-01-00-0a-35

Kernel driver in use: my_driver

Kernel modules: my_driver