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Diffstat (limited to 'Documentation/ABI/testing/pstore')
| -rw-r--r-- | Documentation/ABI/testing/pstore | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/pstore b/Documentation/ABI/testing/pstore new file mode 100644 index 00000000000..ddf451ee2a0 --- /dev/null +++ b/Documentation/ABI/testing/pstore @@ -0,0 +1,41 @@ +Where: /dev/pstore/... +Date: March 2011 +Kernel Version: 2.6.39 +Contact: tony.luck@intel.com +Description: Generic interface to platform dependent persistent storage. + + Platforms that provide a mechanism to preserve some data + across system reboots can register with this driver to + provide a generic interface to show records captured in + the dying moments. In the case of a panic the last part + of the console log is captured, but other interesting + data can also be saved. + + # mount -t pstore -o kmsg_bytes=8000 - /dev/pstore + + $ ls -l /dev/pstore + total 0 + -r--r--r-- 1 root root 7896 Nov 30 15:38 dmesg-erst-1 + + Different users of this interface will result in different + filename prefixes. Currently two are defined: + + "dmesg" - saved console log + "mce" - architecture dependent data from fatal h/w error + + Once the information in a file has been read, removing + the file will signal to the underlying persistent storage + device that it can reclaim the space for later re-use. + + $ rm /dev/pstore/dmesg-erst-1 + + The expectation is that all files in /dev/pstore + will be saved elsewhere and erased from persistent store + soon after boot to free up space ready for the next + catastrophe. + + The 'kmsg_bytes' mount option changes the target amount of + data saved on each oops/panic. Pstore saves (possibly + multiple) files based on the record size of the underlying + persistent storage until at least this amount is reached. + Default is 10 Kbytes. |