Method and system for preserving crash dump in a diskless system

• US 7,484,127 B2
• Filed: 01/13/2005
• Issued: 01/27/2009
• Est. Priority Date: 01/13/2005
• Status: Active Grant

• Current Assignee: Nokia Solutions and Networks US LLC (Nokia Corporation)
• Original Assignee: Nokia Solutions and Networks US LLC (Nokia Corporation)
• Inventors: Babu, Venkatesh
• Primary Examiner(s): McCarthy; Christopher S
• Application Number:
  US11/034,247
• Publication Number:
  US 20060156057A1
• Time in Patent Office: 1,475 Days
• Field of Search: None
• US Class Current: 714/38.11
• CPC Class Codes: G06F 11/0742 in a data processing system embedded in a mobile device, e.g. mobile phones, handheld devices
• CPC Class Codes: G06F 11/0778 Dumping, i.e. gathering error/state information after a fault for later diagnosis
• CPC Class Codes: G06F 11/1441 Resetting or repowering

Abstract

The invention discloses a method for preserving crash dump data in case of operating system crash in a diskless device. The method and the system according to the invention uses two stage booting where in a primary and a secondary kernel are loaded. The primary kernel is a compact kernel that comprises a limited set of functionality and the secondary kernel is a fully functional kernel used for running applications. In case of a crash of the secondary kernel, the kernel prepares a jump back to the primary kernel. Then the primary kernel preserves the crash dump support data and secondary kernel'"'"'s RAM contents by sending it to a remote system which can store it on a nonvolatile memory.

Claims

1. A method, comprising:

loading and booting a primary operating system kernel;

preparing environment for booting a secondary operating system kernel by said primary kernel;

loading and booting a secondary operating system kernel, wherein both said primary kernel and said secondary kernel are loaded and booted before a crash;

in case of a crash,

preparing said secondary kernel for jumping back to said primary kernel; and

preserving crash dump data and jumping back to said primary kernel for storing the preserved data.

2. The method according to claim 1, wherein said primary kernel is a stripped version of said secondary kernel.

3. The method according to claim 1, wherein said jumping back to said primary kernel is performed through a boot loader.

4. The method according to claim 3, wherein said primary kernel is configured to determine if the secondary kernel has crashed.

5. The method according to claim 1, said preparing for jumping back to said primary kernel further comprising:

changing a processor from a protected mode to an unprotected mode;

setting up a segmentation, a page and interrupt tables; and

clearing internal caches and buffers.

6. The method according to claim 5, wherein said changing to unprotected mode comprises arranging program code, in virtual memory and physical memory, into exactly same addresses for allowing said changing.

7. The method according to claim 1, wherein preserving crash dump data comprises storing crash dump support data into a non-volatile memory.

8. The method according to claim 1, wherein preserving crash dump data comprises storing crash dump data by transferring said crash dump data to a remote system.

9. A computer program embodied on a computer readable medium, said computer program for preserving crash dump data in a diskless system in a situation where operating system crashes, wherein the computer program performs a method when executed in a data-processing device, the method comprising:

loading and booting a primary operating system kernel;

preparing environment for booting a secondary operating system kernel by said primary kernel;

loading and booting a secondary operating system kernel, wherein both said primary kernel and said secondary kernel are loaded and booted before a crash;

in case of a crash,

preparing said secondary kernel for jumping back to said primary kernel; and

jumping back to said primary kernel for preserving secondary kernel'"'"'s random access memory contents and crash dump support data.

10. The computer program according to claim 9, wherein said primary kernel is a stripped version of said secondary kernel.

11. The computer program according to claim 9, wherein said jumping back to said primary kernel is performed through a boot loader.

12. The computer program according to claim 11, wherein said primary kernel is configured to determine if the secondary kernel has crashed.

13. The computer program according to claim 9, said preparing for jumping back to said primary kernel further comprising:

changing a processor from protected mode to unprotected mode;

setting up a segmentation, a page and interrupt tables; and

clearing internal caches and buffers.

14. The computer program according to claim 13, wherein said changing to unprotected mode comprises arranging program code, in virtual memory and physical memory, into exactly same addresses for allowing said changing.

15. The computer program according to claim 9, wherein preserving crash dump data comprises storing crash dump support data into a non-volatile memory.

16. The computer program according to claim 9, wherein preserving crash dump data comprises storing crash dump data by transferring said crash dump data to a remote system.

17. An apparatus, comprising:

a memory configured to store data and program code;

a processor configured to execute said program code;

a primary kernel configured to be loaded into said memory; and

a secondary kernel configured to execute applications that is loaded into said memory,

wherein said primary kernel and said secondary kernel are each configured to be loaded into said memory and booted before a crash, and

wherein in case of a crash the apparatus is configured to jump from said secondary kernel to said primary kernel.

18. The apparatus according to claim 17, wherein said primary kernel is a stripped version of said secondary kernel.

19. The apparatus according to claim 17, wherein said device further comprises a boot loader for jumping back to said primary kernel.

20. The apparatus according to claim 19, wherein said primary kernel is configured to determine if the secondary kernel has crashed.

21. The apparatus according to claim 17, wherein said processor comprises protected and unprotected modes.

22. The apparatus according to claim 17, wherein said device further comprises a non-volatile memory configured to store crash dump data.

23. The apparatus according to claim 17, wherein said device further comprises a connection to a remote system configured to store crash dump data by transferring said crash dump data to said remote system.

24. A system, comprising:

a first device;

a second device; and

a network connection between said devices,

the first device comprising

a memory configured to store data and program code;

a processor configured to execute said program code;

a primary kernel configured to be loaded into said memory; and

a secondary kernel configured to execute applications that is loaded into said memory, wherein said primary kernel and said secondary kernel are each configured to be loaded into said memory and booted before a crash, and

wherein in case of a crash the first device is configured to jump from said secondary kernel to said primary kernel.

25. The system according to claim 24, wherein said primary kernel of the first device is a stripped version of said secondary kernel of the first device.

26. The system according to claim 24, wherein said first device further comprises a boot loader for jumping back to said primary kernel.

27. The system according to claim 26, wherein said primary kernel is configured to determine if the secondary kernel has crashed.

28. The system according to claim 24, wherein said processor of the first device comprises protected and unprotected modes.

29. The system according to claim 24, wherein said first device further comprises a non-volatile memory configured to store crash dump data.

30. The system according to claim 24, wherein said first device further comprises a connection to a remote system configured to store crash dump data by transferring said crash dump data to said remote system.

31. The system according to claim 30, wherein said second device is configured to receive the crash dump data sent by the first device.

32. An apparatus, comprising:

storing means for storing data and program code;

executing means for executing said program code;

primary application execution means for executing applications that is loaded into said storing means; and

secondary application execution means for executing applications that is loaded into said storing means,

wherein said primary application execution means and said secondary application execution means are each configured to be loaded into said storing means and booted before a crash, and

wherein in case of a crash the apparatus is configured to jump from said secondary application execution means to said primary application execution means.