1Ramoops oops/panic logger 2========================= 3 4ramoops provides persistent RAM storage for oops and panics, so they can be 5recovered after a reboot. This is a child-node of "/reserved-memory", and 6is named "ramoops" after the backend, rather than "pstore" which is the 7subsystem. 8 9Parts of this storage may be set aside for other persistent log buffers, such 10as kernel log messages, or for optional ECC error-correction data. The total 11size of these optional buffers must fit in the reserved region. 12 13Any remaining space will be used for a circular buffer of oops and panic 14records. These records have a configurable size, with a size of 0 indicating 15that they should be disabled. 16 17At least one of "record-size", "console-size", "ftrace-size", or "pmsg-size" 18must be set non-zero, but are otherwise optional as listed below. 19 20 21Required properties: 22 23- compatible: must be "ramoops" 24 25- reg: region of memory that is preserved between reboots 26 27 28Optional properties: 29 30- ecc-size: enables ECC support and specifies ECC buffer size in bytes 31 (defaults to 0: no ECC) 32 33- record-size: maximum size in bytes of each dump done on oops/panic 34 (defaults to 0: disabled) 35 36- console-size: size in bytes of log buffer reserved for kernel messages 37 (defaults to 0: disabled) 38 39- ftrace-size: size in bytes of log buffer reserved for function tracing and 40 profiling (defaults to 0: disabled) 41 42- pmsg-size: size in bytes of log buffer reserved for userspace messages 43 (defaults to 0: disabled) 44 45- unbuffered: if present, use unbuffered mappings to map the reserved region 46 (defaults to buffered mappings) 47 48- no-dump-oops: if present, only dump panics (defaults to panics and oops) 49 50- flags: if present, pass ramoops behavioral flags (defaults to 0, 51 see include/linux/pstore_ram.h RAMOOPS_FLAG_* for flag values). 52