kdump issue in imx7d

[vadivelmurugan]

Hi,

  I am trying load crashdump kernel and production kernel(normal boot kernel) , normal kernel load without any issue,

  but crash dump kernel load but not executed , it hangs after display Bye message, what is the problem.

  kindly some expert may help us.

  Thank you in Advance.

root@imx6ul7d:~# kexec -e#

Message from syslogd@imx6ul7d at Wed May 10 10:32:28 2017 ...
imx6ul7d kernel: kexec: Starting new kernel
CPU1: shutdown
Bye!

[joanxie]

did you try to build linux Kernel and make sure that the feature kexec and debug info are enable.

·         Boot options  —> 

·         [*] Kexec system call (EXPERIMENTAL)

Kernel hacking  —>

·         [*] Compile the kernel with debug info

[vadivelmurugan]

Hi Joan,

Yes , I have enabled those options in menuconfig

LOG:

root@imx6ul7d:~# kexec -d -p /boot/zImage --dtb=/boot/imx7d-sdb.dtb --command-line="console=ttymxc0,115200 init=/init root=/dev/mmcblk2p2 rw rootfstype=ext3 rootwait reset_devices"
my_load:667: do
Try gzip decompression.
kernel: 0x76969008 kernel_size: 0x448df8
phys_offset: 0x80000000
kernel symbol _stext vaddr = 80008280
page_offset is set to 80000000
get_crash_notes_per_cpu: crash_notes addr = ab72f538, size = 180
Elf header: p_type = 4, p_offset = 0xab72f538 p_paddr = 0xab72f538 p_vaddr = 0x0 p_filesz = 0xb4 p_memsz = 0xb4
get_crash_notes_per_cpu: crash_notes addr = ab73a538, size = 180
Elf header: p_type = 4, p_offset = 0xab73a538 p_paddr = 0xab73a538 p_vaddr = 0x0 p_filesz = 0xb4 p_memsz = 0xb4
vmcoreinfo header: p_type = 4, p_offset = 0x807f8fc4 p_paddr = 0x807f8fc4 p_vaddr = 0x0 p_filesz = 0x1024 p_memsz = 0x1024
Elf header: p_type = 1, p_offset = 0x80000000 p_paddr = 0x80000000 p_vaddr = 0x80000000 p_filesz = 0x7800000 p_memsz = 0x7800000
Elf header: p_type = 1, p_offset = 0x8aa00000 p_paddr = 0x8aa00000 p_vaddr = 0x8aa00000 p_filesz = 0x35600000 p_memsz = 0x35600000
elfcorehdr: 0x8a900000
crashkernel: [0x87800000 - 0x8a9fffff] (50M)
memory range: [0x80000000 - 0x877fffff] (120M)
memory range: [0x8aa00000 - 0xbfffffff] (854M)
kernel command line: "console=ttymxc0,115200 init=/init root=/dev/mmcblk2p2 rw rootfstype=ext3 rootwait reset_devices elfcorehdr=0x8a900000 mem=50176K"
kexec_load: entry = 0x87808000 flags = 0x280001
nr_segments = 3
segment[0].buf = 0x76969008
segment[0].bufsz = 0x448df8
segment[0].mem = 0x87808000
segment[0].memsz = 0x449000
segment[1].buf = 0x137f838
segment[1].bufsz = 0x6e6b
segment[1].mem = 0x88925000
segment[1].memsz = 0x7000
segment[2].buf = 0x137f3f8
segment[2].bufsz = 0x400
segment[2].mem = 0x8a900000
segment[2].memsz = 0x1000
root@imx6ul7d:~# echo c > /proc/sysrq-trigger
sysrq: SysRq : Trigger a crash
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = a8498000
[00000000] *pgd=a893e831, *pte=00000000, *ppte=00000000
Internal error: Oops: 817 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 601 Comm: sh Not tainted 4.1.38-gd5c2679-dirty #58
Hardware name: Freescale i.MX7 Dual (Device Tree)
task: a8813900 ti: a8588000 task.ti: a8588000
PC is at sysrq_handle_crash+0x38/0x40
LR is at __handle_sysrq+0xac/0x178
pc : [<802b8c44>] lr : [<802b93f4>] psr: 600c0013
sp : a8589eb8 ip : 00000003 fp : 00000000
r10: 00000000 r9 : 003151f8 r8 : 00000000
r7 : 00000007 r6 : 00000063 r5 : 80797f6c r4 : 80789ca4
r3 : 00000000 r2 : 00000001 r1 : a8589e30 r0 : 00000063
Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user
Control: 10c53c7d Table: a849806a DAC: 00000015
Process sh (pid: 601, stack limit = 0xa8588210)
Stack: (0xa8589eb8 to 0xa858a000)
9ea0: 802b8c0c 802b93f4
9ec0: 00000002 00000000 00000000 a827f780 00000002 802b98d8 00000001 80138e8c
9ee0: a8589f80 a85613c0 003151f8 a85613c0 00000002 800e7210 00000000 8028a7b0
9f00: 00000000 a800ac00 00000001 a800ad88 00000001 00000002 003151f8 800e940c
9f20: 00000020 00000000 a85613c0 7e919450 76f0ed58 00000001 000000c5 a85613c0
9f40: a85613c0 003151f8 a8589f80 00000002 00000002 800e79e0 00000004 00008080
9f60: 00000001 00000000 00000000 a85613c0 a85613c0 00000002 003151f8 800e81e8
9f80: 00000000 00000000 5912faf4 00000002 003151f8 76f0ed58 00000004 8000f2c4
9fa0: a8588000 8000f140 00000002 003151f8 00000001 003151f8 00000002 00000000
9fc0: 00000002 003151f8 76f0ed58 00000004 00000002 000eb124 00000001 00000000
9fe0: 00000000 7e9199ac 76e3ec18 76e965c0 600c0010 00000001 abf5b811 abf5bc11
[<802b8c44>] (sysrq_handle_crash) from [<802b93f4>] (__handle_sysrq+0xac/0x178)
[<802b93f4>] (__handle_sysrq) from [<802b98d8>] (write_sysrq_trigger+0x38/0x48)
[<802b98d8>] (write_sysrq_trigger) from [<80138e8c>] (proc_reg_write+0x5c/0x84)
[<80138e8c>] (proc_reg_write) from [<800e7210>] (__vfs_write+0x20/0xd8)
[<800e7210>] (__vfs_write) from [<800e79e0>] (vfs_write+0x94/0x154)
[<800e79e0>] (vfs_write) from [<800e81e8>] (SyS_write+0x40/0x94)
[<800e81e8>] (SyS_write) from [<8000f140>] (ret_fast_syscall+0x0/0x3c)
Code: 0a000000 e12fff33 e3a03000 e3a02001 (e5c32000)
CPU 1 will stop doing anything useful since another CPU has crashed
Loading crashdump kernel...
Bye!

Regards

Murugan R

[joanxie]

refer to you uboot command, Memory for crashkernel is not reserved, like add "reservedcrashkernel=128" in the uboot command

[vadivelmurugan]

It hangs that point , please answer the following doubts:

1.how to load initramfs for capture dump kernel?

2.waht is issue in the aboe logs? where to dig to getout of this problem?