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2024-02-20 102a0743326a03cd1a1202ceda21e175b7d3575c

 kernel/Documentation/devicetree/bindings/reserved-memory/ramoops.txt
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@@ -30,7 +30,7 @@
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 - ecc-size: enables ECC support and specifies ECC buffer size in bytes
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   (defaults to 0: no ECC)
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-- record-size: maximum size in bytes of each dump done on oops/panic
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+- record-size: maximum size in bytes of each kmsg dump.
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   (defaults to 0: disabled)
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 - console-size: size in bytes of log buffer reserved for kernel messages
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@@ -42,10 +42,25 @@
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 - pmsg-size: size in bytes of log buffer reserved for userspace messages
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   (defaults to 0: disabled)
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-- unbuffered: if present, use unbuffered mappings to map the reserved region
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-  (defaults to buffered mappings)
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+- mem-type: if present, sets the type of mapping is to be used to map the
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+  reserved region. mem-type: 0 = write-combined (default), 1 = unbuffered,
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+  2 = cached.
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-- no-dump-oops: if present, only dump panics (defaults to panics and oops)
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+- unbuffered: deprecated, use mem_type instead. if present, and mem_type is
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+  not specified, it is equivalent to mem_type = 1 and uses unbuffered mappings
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+  to map the reserved region (defaults to buffered mappings mem_type = 0). If
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+  both are specified -- "mem_type" overrides "unbuffered".
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+
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+- max-reason: if present, sets maximum type of kmsg dump reasons to store
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+  (defaults to 2: log Oopses and Panics). This can be set to INT_MAX to
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+  store all kmsg dumps. See include/linux/kmsg_dump.h KMSG_DUMP_* for other
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+  kmsg dump reason values. Setting this to 0 (KMSG_DUMP_UNDEF), means the
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+  reason filtering will be controlled by the printk.always_kmsg_dump boot
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+  param: if unset, it will be KMSG_DUMP_OOPS, otherwise KMSG_DUMP_MAX.
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+
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+- no-dump-oops: deprecated, use max_reason instead. If present, and
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+  max_reason is not specified, it is equivalent to max_reason = 1
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+  (KMSG_DUMP_PANIC).
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 - flags: if present, pass ramoops behavioral flags (defaults to 0,
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   see include/linux/pstore_ram.h RAMOOPS_FLAG_* for flag values).