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Based on kernel version 3.13. Page generated on 2014-01-20 21:59 EST.

1	Where:		/sys/fs/pstore/... (or /dev/pstore/...)
2	Date:		March 2011
3	Kernel Version: 2.6.39
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 -o kmsg_bytes=8000 - /sys/fs/pstore
15	
16			$ ls -l /sys/fs/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 /sys/fs/pstore/dmesg-erst-1
31	
32			The expectation is that all files in /sys/fs/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.
36	
37			The 'kmsg_bytes' mount option changes the target amount of
38			data saved on each oops/panic. Pstore saves (possibly
39			multiple) files based on the record size of the underlying
40			persistent storage until at least this amount is reached.
41			Default is 10 Kbytes.
42	
43			Pstore only supports one backend at a time. If multiple
44			backends are available, the preferred backend may be
45			set by passing the pstore.backend= argument to the kernel at
46			boot time.
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