From: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Currently, it is possible to dump kmsges for panic, or oops. With max_reason it is possible to dump messages for other kmesg_dump events, for example reboot, halt, shutdown, kexec. Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Link: https://lore.kernel.org/lkml/20200506211523.15077-6-keescook@xxxxxxxxxxxx/ Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- .../devicetree/bindings/reserved-memory/ramoops.txt | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/Documentation/devicetree/bindings/reserved-memory/ramoops.txt b/Documentation/devicetree/bindings/reserved-memory/ramoops.txt index 0eba562fe5c6..b7886fea368c 100644 --- a/Documentation/devicetree/bindings/reserved-memory/ramoops.txt +++ b/Documentation/devicetree/bindings/reserved-memory/ramoops.txt @@ -30,7 +30,7 @@ Optional properties: - ecc-size: enables ECC support and specifies ECC buffer size in bytes (defaults to 0: no ECC) -- record-size: maximum size in bytes of each dump done on oops/panic +- record-size: maximum size in bytes of each kmsg dump. (defaults to 0: disabled) - console-size: size in bytes of log buffer reserved for kernel messages @@ -45,7 +45,16 @@ Optional properties: - unbuffered: if present, use unbuffered mappings to map the reserved region (defaults to buffered mappings) -- no-dump-oops: if present, only dump panics (defaults to panics and oops) +- max-reason: if present, sets maximum type of kmsg dump reasons to store + (defaults to 2: log Oopses and Panics). This can be set to INT_MAX to + store all kmsg dumps. See include/linux/kmsg_dump.h KMSG_DUMP_* for other + kmsg dump reason values. Setting this to 0 (KMSG_DUMP_UNDEF), means the + reason filtering will be controlled by the printk.always_kmsg_dump boot + param: if unset, it will be KMSG_DUMP_OOPS, otherwise KMSG_DUMP_MAX. + +- no-dump-oops: deprecated, use max_reason instead. If present, and + max_reason is not specified, it is equivalent to max_reason = 1 + (KMSG_DUMP_PANIC). - flags: if present, pass ramoops behavioral flags (defaults to 0, see include/linux/pstore_ram.h RAMOOPS_FLAG_* for flag values). -- 2.20.1