projects / mirror_ubuntu-zesty-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| ca01d6dd TL |
1 | Where: /dev/pstore/... |
| 2 | Date: January 2011 | |
| 3 | Kernel Version: 2.6.38 | |
| 4 | Contact: tony.luck@intel.com | |
| 5 | Description: Generic interface to platform dependent persistent storage. | |
| 6 | ||
| 7 | Platforms that provide a mechanism to preserve some data | |
| 8 | across system reboots can register with this driver to | |
| 9 | provide a generic interface to show records captured in | |
| 10 | the dying moments. In the case of a panic the last part | |
| 11 | of the console log is captured, but other interesting | |
| 12 | data can also be saved. | |
| 13 | ||
| 14 | # mount -t pstore - /dev/pstore | |
| 15 | ||
| 16 | $ ls -l /dev/pstore | |
| 17 | total 0 | |
| 18 | -r--r--r-- 1 root root 7896 Nov 30 15:38 dmesg-erst-1 | |
| 19 | ||
| 20 | Different users of this interface will result in different | |
| 21 | filename prefixes. Currently two are defined: | |
| 22 | ||
| 23 | "dmesg" - saved console log | |
| 24 | "mce" - architecture dependent data from fatal h/w error | |
| 25 | ||
| 26 | Once the information in a file has been read, removing | |
| 27 | the file will signal to the underlying persistent storage | |
| 28 | device that it can reclaim the space for later re-use. | |
| 29 | ||
| 30 | $ rm /dev/pstore/dmesg-erst-1 | |
| 31 | ||
| 32 | The expectation is that all files in /dev/pstore | |
| 33 | will be saved elsewhere and erased from persistent store | |
| 34 | soon after boot to free up space ready for the next | |
| 35 | catastrophe. |