hello all
I am a newbie in Linux forum as well as in kernal development. I am working on a custom built board based on NXP's T1042 processor with on-board discrete DDR3L RAM.
I have flashed UBOOT, file-system, kernel, dtb file, etc in the boot flash. When I boot-up the board, the kernal is crashing at a fixed location prompting the error that Unable to handle kernal paging request at 0x00000104. Kernel logs are provided as under.

My question is what is the physical address of RAM for this virtual address 0x00000104?
And whys is my kernal crashing at this specific address. I have other boards also on which same files work properly so I am trying to debug this particular board.

Below are the kernal logs

WARNING: adjusting available memory to 30000000
## Booting kernel from Legacy Image at e8020000 ...
Image Name: Linux-4.1.35-rt41
Image Type: PowerPC Linux Kernel Image (gzip compressed)
Data Size: 4628199 Bytes = 4.4 MiB
Load Address: 00000000
Entry Point: 00000000
Verifying Checksum ... OK
## Loading init Ramdisk from Legacy Image at e9300000 ...
Image Name: fsl-image-core-t1042d4rdb-201605
Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
Data Size: 31556452 Bytes = 30.1 MiB
Load Address: 00000000
Entry Point: 00000000
Verifying Checksum ... OK
## Flattened Device Tree blob at e8800000
Booting using the fdt blob at 0xe8800000
Uncompressing Kernel Image ... OK
Loading Ramdisk to 021e7000, end 03fff364 ... OK
Loading Device Tree to 021cb000, end 021e64be ... OK
Reserved memory: initialized node bman-fbpr, compatible id fsl,bman-fbpr
Reserved memory: initialized node qman-fqd, compatible id fsl,qman-fqd
Reserved memory: initialized node qman-pfdr, compatible id fsl,qman-pfdr
Reserved memory: initialized node pme-pdsr, compatible id fsl,pme-pdsr
Reserved memory: initialized node pme-sre, compatible id fsl,pme-sre
Using CoreNet Generic machine description
Memory CAM mapping: 256/256/256 Mb, residual: 1280Mb
Linux version 4.1.35-rt41 (mas1496@ubuntu) (gcc version 4.9.2 (GCC) ) #1 SMP Sat Feb 2 17:34:02 PKT 2019
Found initrd at 0xc21e7000:0xc3fff364
CPU maps initialized for 1 thread per core
bootconsole [udbg0] enabled
setup_arch: initmem
CoreNet Generic board
arch: exit
Zone ranges:
DMA [mem 0x0000000000000000-0x000000002fffffff]
Normal empty
HighMem [mem 0x0000000030000000-0x000000007fffffff]
Movable zone start for each node
Early memory node ranges
node 0: [mem 0x0000000000000000-0x000000007fffffff]
Initmem setup node 0 [mem 0x0000000000000000-0x000000007fffffff]
MMU: Allocated 1088 bytes of context maps for 255 contexts
PERCPU: Embedded 12 pages/cpu @eef7c000 s19148 r8192 d21812 u49152
Built 1 zonelists in Zone order, mobility grouping on. Total pages: 522752
Kernel command line: root=/dev/ram rw console=ttyS0,115200 ramdisk_size=1000000
log_buf_len individual max cpu contribution: 4096 bytes
log_buf_len total cpu_extra contributions: 12288 bytes
log_buf_len min size: 16384 bytes
log_buf_len: 32768 bytes
early log buf free: 13284(81%)
PID hash table entries: 4096 (order: 2, 16384 bytes)
Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
Sorting __ex_table...
Memory: 1888248K/2097152K available (7200K kernel code, 312K rwdata, 2056K rodata, 316K init, 458K bss, 208904K reserved, 0K cma-reserved, 1226744K highmem)
Kernel virtual memory layout:
* 0xfff5f000..0xfffff000 : fixmap
* 0xffc00000..0xffe00000 : highmem PTEs
* 0xffbfd000..0xffc00000 : early ioremap
* 0xf1000000..0xffbfd000 : vmalloc & ioremap
Hierarchical RCU implementation.
RCU debugfs-based tracing is enabled.
Additional per-CPU info printed with stalls.
RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=4.
RCU: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=4
NR_IRQS:512 nr_irqs:512 16
mpic: Setting up MPIC " OpenPIC " version 1.2 at ffe040000, max 4 CPUs
mpic: ISU size: 512, shift: 9, mask: 1ff
mpic: Initializing for 512 sources
clocksource timebase: mask: 0xffffffffffffffff max_cycles: 0x8a60dd6a9, max_idle_ns: 440795204056 ns
clocksource: timebase mult[1aaaaaab] shift[24] registered
Console: colour dummy device 80x25
pid_max: default: 32768 minimum: 301
Mount-cache hash table entries: 2048 (order: 1, 8192 bytes)
Mountpoint-cache hash table entries: 2048 (order: 1, 8192 bytes)
e500 family performance monitor hardware support registered
Brought up 4 CPUs
devtmpfs: initialized
clocksource jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
NET: Registered protocol family 16
Bman ver:0a02,02,01
qman-fqd addr 0x000000007f000000 size 0x800000
qman-pfdr addr 0x000000007c000000 size 0x2000000
Qman ver:0a01,03,01,03

Machine: fsl,T1042D4RDB
SoC family: QorIQ T1040
SoC ID: svr:0x85280211, Revision: 1.1
Can't find hose for PCI bus 0!
EDAC PCI0: Giving out device to module MPC85xx_edac controller mpc85xx_pci_err: DEV ffe240000.pcie (INTERRUPT)
MPC85xx_edac acquired irq 20 for PCI Err
MPC85xx_edac PCI err registered
Can't find hose for PCI bus 0!
EDAC PCI1: Giving out device to module MPC85xx_edac controller mpc85xx_pci_err: DEV ffe250000.pcie (INTERRUPT)
MPC85xx_edac acquired irq 21 for PCI Err
MPC85xx_edac PCI err registered
Can't find hose for PCI bus 0!
EDAC PCI2: Giving out device to module MPC85xx_edac controller mpc85xx_pci_err: DEV ffe260000.pcie (INTERRUPT)
MPC85xx_edac acquired irq 22 for PCI Err
MPC85xx_edac PCI err registered
Can't find hose for PCI bus 0!
EDAC PCI3: Giving out device to module MPC85xx_edac controller mpc85xx_pci_err: DEV ffe270000.pcie (INTERRUPT)
MPC85xx_edac acquired irq 23 for PCI Err
MPC85xx_edac PCI err registered
PCI: Probing PCI hardware
vgaarb: loaded
SCSI subsystem initialized
usbcore: registered new interface driver usbfs
usbcore: registered new interface driver hub
usbcore: registered new device driver usb
pps_core: LinuxPPS API ver. 1 registered
pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti <giometti@linux.it>
PTP clock support registered
EDAC MC: Ver: 3.0.0
bman-fbpr addr 0x000000007e000000 size 0x1000000
Bman err interrupt handler present
Bman portal initialised, cpu 0
Bman portal initialised, cpu 1
Bman portal initialised, cpu 2
Bman portal initialised, cpu 3
Bman portals initialised
Qman err interrupt handler present
Qman portal initialised, cpu 0
Qman portal initialised, cpu 1
Qman portal initialised, cpu 2
Qman portal initialised, cpu 3
Qman portals initialised
Bman: BPID allocator includes range 32:32
Qman: FQID allocator includes range 256:512
Qman: FQID allocator includes range 32768:32768
Qman: CGRID allocator includes range 0:256
Qman: pool channel allocator includes range 1025:15
No USDPAA memory, no 'fsl,usdpaa-mem' in device-tree
fsl-ifc ffe124000.localbus: Freescale Integrated Flash Controller
fsl-ifc ffe124000.localbus: IFC version 1.3, 8 banks
Switched to clocksource timebase
NET: Registered protocol family 2
TCP established hash table entries: 8192 (order: 3, 32768 bytes)
TCP bind hash table entries: 8192 (order: 4, 65536 bytes)
TCP: Hash tables configured (established 8192 bind 8192)
UDP hash table entries: 512 (order: 2, 16384 bytes)
UDP-Lite hash table entries: 512 (order: 2, 16384 bytes)
NET: Registered protocol family 1
RPC: Registered named UNIX socket transport module.
RPC: Registered udp transport module.
RPC: Registered tcp transport module.
RPC: Registered tcp NFSv4.1 backchannel transport module.
Trying to unpack rootfs image as initramfs...
rootfs image is not initramfs (no cpio magic); looks like an initrd
Freeing initrd memory: 30816K (c21e7000 - c3fff000)
futex hash table entries: 1024 (order: 4, 65536 bytes)
audit: initializing netlink subsys (disabled)
audit: type=2000 audit(0.524:1): initialized
HugeTLB registered 4 MB page size, pre-allocated 0 pages
HugeTLB registered 16 MB page size, pre-allocated 0 pages
HugeTLB registered 64 MB page size, pre-allocated 0 pages
HugeTLB registered 256 MB page size, pre-allocated 0 pages
HugeTLB registered 1 GB page size, pre-allocated 0 pages
NFS: Registering the id_resolver key type
Key type id_resolver registered
Key type id_legacy registered
ntfs: driver 2.1.32 [Flags: R/O].
jffs2: version 2.2. (NAND) © 2001-2006 Red Hat, Inc.
bounce: pool size: 64 pages
io scheduler noop registered
io scheduler deadline registered
io scheduler cfq registered (default)
Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
¦¦¦¦¦¦¦250.0: ttyS0 at MMIO 0xffe11c500 (irq = 36, base_baud = 18750000) is a 16550A_FSL64
console [ttyS0] enabled
console [ttyS0] enabled
bootconsole [udbg0] disabled
bootconsole [udbg0] disabled
serial8250.0: ttyS1 at MMIO 0xffe11c600 (irq = 36, base_baud = 18750000) is a 16550A_FSL64
serial8250.0: ttyS2 at MMIO 0xffe11d500 (irq = 37, base_baud = 18750000) is a 16550A_FSL64
serial8250.0: ttyS3 at MMIO 0xffe11d600 (irq = 37, base_baud = 18750000) is a 16550A_FSL64
ePAPR hypervisor byte channel driver
Generic non-volatile memory driver v1.1
brd: module loaded
loop: module loaded
st: Version 20101219, fixed bufsize 32768, s/g segs 256
fsl-sata ffe220000.sata: Sata FSL Platform/CSB Driver init
scsi host0: sata_fsl
ata1: SATA max UDMA/133 irq 68
fsl-sata ffe221000.sata: Sata FSL Platform/CSB Driver init
scsi host1: sata_fsl
ata2: SATA max UDMA/133 irq 69
fe8000000.nor: Found 1 x16 devices at 0x0 in 16-bit bank. Manufacturer ID 0x000089 Chip ID 0x00227e
Amd/Fujitsu Extended Query Table at 0x0040
Amd/Fujitsu Extended Query version 1.3.
number of CFI chips: 1
fsl,ifc-nand fff800000.nand: fsl_ifc_nand_probe: address did not match any chip selects
libphy: Fixed MDIO Bus: probed
libphy: Freescale XGMAC MDIO Bus: probed
libphy: Freescale XGMAC MDIO Bus: probed
libphy: Freescale XGMAC MDIO Bus: probed
libphy: Freescale XGMAC MDIO Bus: probed
libphy: Freescale XGMAC MDIO Bus: probed
libphy: Freescale XGMAC MDIO Bus: probed
Freescale FM module, FMD API version 21.1.0
Freescale FM Ports module
fsl_mac: fsl_mac: FSL FMan MAC API based driver
fsl_mac ffe4e6000.ethernet: FMan MEMAC
fsl_mac ffe4e6000.ethernet: FMan MAC address: 00:04:9f:03:3b:49
fsl_mac ffe4e8000.ethernet: FMan MEMAC
fsl_mac ffe4e8000.ethernet: FMan MAC address: 00:04:9f:03:3b:4a
fsl_dpa: FSL DPAA Ethernet driver
fsl_dpa: fsl_dpa: Probed interface eth0
fsl_dpa: fsl_dpa: Probed interface eth1
fsl_advanced: FSL DPAA Advanced drivers:
fsl_proxy: FSL DPAA Proxy initialization driver
fsl_dpa_shared: FSL DPAA Shared Ethernet driver
fsl_dpa_macless: FSL DPAA MACless Ethernet driver
fsl_oh: FSL FMan Offline Parsing port driver
e1000: Intel(R) PRO/1000 Network Driver - version 7.3.21-k8-NAPI
e1000: Copyright (c) 1999-2006 Intel Corporation.
e1000e: Intel(R) PRO/1000 Network Driver - 2.3.2-k
e1000e: Copyright(c) 1999 - 2014 Intel Corporation.
ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
ehci-pci: EHCI PCI platform driver
ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
ohci-pci: OHCI PCI platform driver
/soc@ffe000000/usb@210000: Invalid 'dr_mode' property, fallback to host mode
fsl-ehci fsl-ehci.0: Freescale On-Chip EHCI Host Controller
fsl-ehci fsl-ehci.0: new USB bus registered, assigned bus number 1
fsl-ehci fsl-ehci.0: irq 44, io mem 0xffe210000
fsl-ehci fsl-ehci.0: USB 2.0 started, EHCI 1.00
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 1 port detected
fsl-ehci fsl-ehci.1: Freescale On-Chip EHCI Host Controller
fsl-ehci fsl-ehci.1: new USB bus registered, assigned bus number 2
fsl-ehci fsl-ehci.1: irq 45, io mem 0xffe211000
fsl-ehci fsl-ehci.1: USB 2.0 started, EHCI 1.00
hub 2-0:1.0: USB hub found
hub 2-0:1.0: 1 port detected
usbcore: registered new interface driver usb-storage
i2c /dev entries driver
mpc-i2c ffe118000.i2c: timeout 1000000 us
rtc-ds1307 0-0068: SET TIME!
rtc-ds1307 0-0068: rtc core: registered ds1337 as rtc0
mpc-i2c ffe118100.i2c: timeout 1000000 us
mpc-i2c ffe119000.i2c: timeout 1000000 us
mpc-i2c ffe119100.i2c: timeout 1000000 us
pca954x 1-0077: probe failed
Freescale(R) MPC85xx EDAC driver, (C) 2006 Montavista Software
mpc85xx_mc_err_probe: No ECC DIMMs discovered
qoriq_cpufreq: Freescale QorIQ CPU frequency scaling driver
sdhci: Secure Digital Host Controller Interface driver
sdhci: Copyright(c) Pierre Ossman
sdhci-pltfm: SDHCI platform and OF driver helper
/soc@ffe000000/sdhc@114000: voltage-ranges unspecified
sdhci-esdhc ffe114000.sdhc: No vmmc regulator found
sdhci-esdhc ffe114000.sdhc: No vqmmc regulator found
mmc0: SDHCI controller on ffe114000.sdhc [ffe114000.sdhc] using ADMA 64-bit
platform caam_qi: Linux CAAM Queue I/F driver initialised
caam ffe300000.crypto: Instantiated RNG4 SH1
caam ffe300000.crypto: device ID = 0x0a12040000000000 (Era 6)
caam ffe300000.crypto: job rings = 4, qi = 1
caam algorithms registered in /proc/crypto
platform caam_qi: algorithms registered in /proc/crypto
caam_jr ffe301000.jr: registering rng-caam
caam ffe300000.crypto: fsl,sec-v5.0 algorithms registered in /proc/crypto
Freescale USDPAA process driver
fsl-usdpaa: no region found
Freescale USDPAA process IRQ driver
fsl-pme ffe316000.pme: ver: 0x00100202
Freescale pme2 db driver
Freescale pme2 scan driver
fsl-pme2-scan: device pme_scan registered
Freescale hypervisor management driver
fsl-hv: no hypervisor found
ipip: IPv4 over IPv4 tunneling driver
Initializing XFRM netlink socket
NET: Registered protocol family 10
ata1: No Device OR PHYRDY change,Hstatus = 0x80000000
ata1: SATA link down (SStatus 10 SControl 300)
ata2: No Device OR PHYRDY change,Hstatus = 0x80000000
ata2: SATA link down (SStatus 10 SControl 300)
sit: IPv6 over IPv4 tunneling driver
NET: Registered protocol family 17
NET: Registered protocol family 15
8021q: 802.1Q VLAN Support v1.8
Key type dns_resolver registered
fsl_generic: FSL DPAA Generic Ethernet driver
rtc-ds1307 0-0068: setting system clock to 2000-01-01 00:01:07 UTC (946684867)
RAMDISK: gzip image found at block 0
Unable to handle kernel paging request for data at address 0x00000104
Faulting instruction address: 0xc00c79a8
Oops: Kernel access of bad area, sig: 11 [#1]
SMP NR_CPUS=8 CoreNet Generic
Modules linked in:
CPU: 3 PID: 1 Comm: swapper/0 Not tainted 4.1.35-rt41 #1
task: e9047910 ti: e9048000 task.ti: e9048000
NIP: c00c79a8 LR: c00c8130 CTR: 00000000
REGS: e90499e0 TRAP: 0300 Not tainted (4.1.35-rt41)
MSR: 00021002 <CE,ME> CR: 42228e28 XER: 20000000
DEAR: 00000104 ESR: 00800000
GPR00: c00c8130 e9049a90 e9047910 c099e640 00000000 00000002 eefcb3f4 00000001
GPR08: 00000100 c099e6f4 c099e6e4 eefcb3f4 c099e6d0 00000000 c0854b98 00000002
GPR16: eefa6ae8 2e648000 eeeeeeef c0959d3c ffffffff e9049b68 00000010 c0854be8
GPR24: c09a7df0 00029002 00000002 c099e640 00000000 ef513894 00000010 ef513880
NIP [c00c79a8] __rmqueue+0x68/0x3a0
LR [c00c8130] get_page_from_freelist+0x450/0x640
Call Trace:
[e9049a90] [c00c6eec] free_hot_cold_page+0x2c/0x1b0 (unreliable)
[e9049ae0] [c00c8130] get_page_from_freelist+0x450/0x640
[e9049b60] [c00c85a0] __alloc_pages_nodemask+0xf0/0x7a0
[e9049bf0] [c00c0c28] pagecache_get_page+0x88/0x220
[e9049c30] [c0142894] __getblk_slow+0x104/0x370
[e9049ca0] [c0143034] __bread_gfp+0x14/0x110
[e9049cb0] [c018b988] ext3_fill_super+0x218/0x1960
[e9049d30] [c010fa50] mount_bdev+0x1b0/0x1e0
[e9049d80] [c01106b0] mount_fs+0x20/0xa0
[e9049da0] [c012d324] vfs_kern_mount+0x54/0x140
[e9049dc0] [c0130d00] do_mount+0x190/0xc00
[e9049e20] [c0131b28] SyS_mount+0x78/0xe0
[e9049e50] [c090eebc] mount_block_root+0x120/0x24c
[e9049ea0] [c090f220] mount_root+0x100/0x114
[e9049ee0] [c090f3c0] prepare_namespace+0x18c/0x1d4
[e9049f00] [c090ebc0] kernel_init_freeable+0x1bc/0x1d0
[e9049f30] [c0002714] kernel_init+0x14/0x110
[e9049f40] [c000f198] ret_from_kernel_thread+0x5c/0x64
Instruction dump:
7d5b4a14 83aa0080 39290080 7f87e378 7d3b4a14 39480080 7f9d4840 7d5b5214
41de00e8 813d0004 3bfdffec 811d0000 <91280004> 91090000 39200100 913d0000
---[ end trace 9973bba370f816b8 ]---

Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b