From: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Add a new member to struct pstore_info for passing information about kmesg dump maximum reason. This allows a finer control of what kmesg dumps are sent to pstore storage backends. Those backends that do not explicitly set this field (keeping it equal to 0), get the default behavior: store only Oopses and Panics, or everything if the printk.always_kmsg_dump boot param is set. Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Link: https://lore.kernel.org/lkml/20200506211523.15077-3-keescook@xxxxxxxxxxxx/ Co-developed-by: Kees Cook <keescook@xxxxxxxxxxxx> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- fs/pstore/platform.c | 4 +++- include/linux/pstore.h | 7 +++++++ 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 5e6c6022deb9..a9e297eefdff 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -595,8 +595,10 @@ int pstore_register(struct pstore_info *psi) pstore_get_records(0); - if (psi->flags & PSTORE_FLAGS_DMESG) + if (psi->flags & PSTORE_FLAGS_DMESG) { + pstore_dumper.max_reason = psinfo->max_reason; pstore_register_kmsg(); + } if (psi->flags & PSTORE_FLAGS_CONSOLE) pstore_register_console(); if (psi->flags & PSTORE_FLAGS_FTRACE) diff --git a/include/linux/pstore.h b/include/linux/pstore.h index f6f22b13e04f..eb93a54cff31 100644 --- a/include/linux/pstore.h +++ b/include/linux/pstore.h @@ -96,6 +96,12 @@ struct pstore_record { * * @read_mutex: serializes @open, @read, @close, and @erase callbacks * @flags: bitfield of frontends the backend can accept writes for + * @max_reason: Used when PSTORE_FLAGS_DMESG is set. Contains the + * kmsg_dump_reason enum value. KMSG_DUMP_UNDEF means + * "use existing kmsg_dump() filtering, based on the + * printk.always_kmsg_dump boot param" (which is either + * KMSG_DUMP_OOPS when false, or KMSG_DUMP_MAX when + * true); see printk.always_kmsg_dump for more details. * @data: backend-private pointer passed back during callbacks * * Callbacks: @@ -179,6 +185,7 @@ struct pstore_info { struct mutex read_mutex; int flags; + int max_reason; void *data; int (*open)(struct pstore_info *psi); -- 2.20.1
