# No core dumps found



## sham1810 (Nov 20, 2018)

Hi,

I have FreeBSD installed on an amd64 platform and when I boot, the screen goes blank during kernel initialization and the system reboots. I'm able to boot if I set the loader tunable hw.pci.mcfg=0. Now, in order to figure out why the system reboots, I need some debug information. After the reboot, there is no crash dump available in /var/crash.

I have the following in my /etc/rc.conf

```
dumpdev="AUTO"
dumpdir="/var/crash"
```

I have a swap disk configured for 27G. As per gpart:

```
255852584    56623104    3   freebsd-swap   (27G)
```

Using serial port I'm able to know where that the kernel crashes during initialization, but there is no stack trace to go on. How can I obtain more information in order to debug this problem? Any suggestions?

Logs from the serial terminal up until the kernel reboots:


```
SmmLockBoxSmmLib UpdateLockBox - Enter
SmmLockBoxSmmLib UpdateLockBox - Exit (Success)
SmmLockBoxSmmLib UpdateLockBox - Enter
SmmLockBoxSmmLib UpdateLockBox - Exit (Success)
SmmInstallProtocolInterface: 296EB418-C4C8-4E05-AB59-39E8AF56F00A 0
SmmLockBoxSmmLib RestoreLockBox - Enter
SmmLockBoxSmmLib RestoreLockBox - Exit (Success)
SmmLockBoxSmmLib SaveLockBox - Enter
LockBoxGuid - B5AF1D7A-B8CF-4EB3-8925-A820E16B687D, SmramBuffer - 0x7F8CE000, Length - 0x389D
SmmLockBoxSmmLib SaveLockBox - Exit (Success)
SmmLockBoxSmmLib SaveLockBox - Enter
LockBoxGuid - 627EE2DA-3BF9-439B-929F-2E0E6E9DBA62, SmramBuffer - 0x7F8CD000, Length - 0x18
SmmLockBoxSmmLib SaveLockBox - Exit (Success)
SmmLockBoxSmmLib SetLockBoxAttributes - Enter
SmmLockBoxSmmLib SetLockBoxAttributes - Exit (Success)
GDB: no debug ports present
KDB: debugger backends: ddb
KDB: current backend: ddb
---<<BOOT>>---
Copyright (c) 1992-2018 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
        The Regents of the University of California. All rights reserved.
FreeBSD is a registered trademark of The FreeBSD Foundation.
FreeBSD 13.0-CURRENT e492486a417(master) GENERIC amd64
FreeBSD clang version 6.0.0 (tags/RELEASE_600/final 326565) (based on LLVM 6.0.0)
WARNING: WITNESS option enabled, expect reduced performance.
VT(efifb): resolution 1280x1024
CPU: AMD xxxxxxxxxxxxxxxxxx           (2295.74-MHz K8-class CPU)
  Origin="AuthenticAMD"  Id=0x800f12  Family=0x17  Model=0x1  Stepping=2
  Features=0x178bfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,MMX,FXSR,SSE,SSE2,HTT>
  Features2=0x7ed8320b<SSE3,PCLMULQDQ,MON,SSSE3,FMA,CX16,SSE4.1,SSE4.2,MOVBE,POPCNT,AESNI,XSAVE,OSXSAVE,AVX,F16C,RDRAND>
  AMD Features=0x2e500800<SYSCALL,NX,MMX+,FFXSR,Page1GB,RDTSCP,LM>
  AMD Features2=0x35c233ff<LAHF,CMP,SVM,ExtAPIC,CR8,ABM,SSE4A,MAS,Prefetch,OSVW,SKINIT,WDT,TCE,Topology,PCXC,PNXC,DBE,PL2I,MWAITX>
  Structured Extended Features=0x209c01a9<FSGSBASE,BMI1,AVX2,SMEP,BMI2,RDSEED,ADX,SMAP,CLFLUSHOPT,SHA>
  XSAVE Features=0xf<XSAVEOPT,XSAVEC,XINUSE,XSAVES>
  AMD Extended Feature Extensions ID EBX=0x1007<CLZERO,IRPerf,XSaveErPtr>
  SVM: NP,NRIP,VClean,AFlush,DAssist,NAsids=32768
  TSC: P-state invariant, performance statistics
real memory  = 17179869184 (16384 MB)
avail memory = 16448143360 (15686 MB)
Event timer "LAPIC" quality 600
ACPI APIC Table: <AMD xxxxxxxx >
FreeBSD/SMP: Multiprocessor System Detected: 16 CPUs
FreeBSD/SMP: 1 package(s) x 2 cache groups x 4 core(s) x 2 hardware threads
random: unblocking device.
ioapic0: Changing APIC ID to 128
ioapic1: Changing APIC ID to 129
ioapic0 <Version 2.1> irqs 0-23 on motherboard
ioapic1 <Version 2.1> irqs 24-55 on motherboard
Launching APs: 15 5 1 10 11 4 7 6 3 2 9 8 14 12 13
Timecounter "TSC-low" frequency 1147871545 Hz quality 1000
random: entropy device external interface
[ath_hal] loaded
kbd0 at kbdmux0
module_register_init: MOD_LOAD (vesa, 0xffffffff810f8190, 0) error 19
random: registering fast source Intel Secure Key RNG
random: fast provider: "Intel Secure Key RNG"
netmap: loaded module
nexus0
efirtc0: <EFI Realtime Clock> on motherboard
efirtc0: registered as a time-of-day clock, resolution 1.000000s
cryptosoft0: <software crypto> on motherboard
acpi0: <AMD> on motherboard
[ererwVrdur
           <na
              [ererwVrdur
```


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## Bobi B. (Nov 20, 2018)

For `dumpdev` option to be applied, the system have to reach the point, where kernel starts init(8) and rc(8)-scripts. It doesn't get there in your case. See dumpon(8); perhaps you can try setting `dumpdev` variable in /boot/loader.conf; search for `dumpdev` in loader(8).


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## sham1810 (Nov 21, 2018)

Bobi B. said:


> For `dumpdev` option to be applied, the system have to reach the point, where kernel starts init(8) and rc(8)-scripts. It doesn't get there in your case. See dumpon(8); perhaps you can try setting `dumpdev` variable in /boot/loader.conf; search for `dumpdev` in loader(8).


I added the following in /boot/loader.conf:
dumpdev="/dev/ada0p3"

and removed dumpdev and dumpdir from /etc/rc.conf. I still don't see a dump in /var/crash.
swapinfo shows my swap partition is 0% used.

/dev/ada0p3 is the swap partition on my disk. Is there anything else I need to configure in order to obtain this dump. What is the usual way to debug crash during early boot stages?


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## SirDice (Nov 21, 2018)

sham1810 said:


> FreeBSD 13.0-CURRENT e492486a417(master) GENERIC amd64


Topics about unsupported FreeBSD versions


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