From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- Documentation/ABI/testing/pstore | 47 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 Documentation/ABI/testing/pstore (limited to 'Documentation/ABI/testing/pstore') diff --git a/Documentation/ABI/testing/pstore b/Documentation/ABI/testing/pstore new file mode 100644 index 000000000..5fca9f5e1 --- /dev/null +++ b/Documentation/ABI/testing/pstore @@ -0,0 +1,47 @@ +Where: /sys/fs/pstore/... (or /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 - /sys/fs/pstore + + $ ls -l /sys/fs/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 /sys/fs/pstore/dmesg-erst-1 + + The expectation is that all files in /sys/fs/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. + + Pstore only supports one backend at a time. If multiple + backends are available, the preferred backend may be + set by passing the pstore.backend= argument to the kernel at + boot time. + -- cgit v1.2.3-54-g00ecf