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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.
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