From: Pavel Tatashin
stable inclusion
from stable-5.10
category: feature
commit:3524e688b8ee50b0edc76f0e020727eb6c684dbc
issue: #I4919J
--------------------------------
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
Link: https://lore.kernel.org/lkml/20200515184434.8470-5-keescook@chromium.org/
Co-developed-by: Kees Cook
Signed-off-by: Kees Cook
(cherry picked from commit 3524e688b8ee50b0edc76f0e020727eb6c684dbc)
Signed-off-by: roger
---
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 405f714b69d3..78058359b18e 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -630,8 +630,10 @@ 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 b146181e8709..c39f8c873df9 100644
--- a/include/linux/pstore.h
+++ b/include/linux/pstore.h
@@ -108,6 +108,12 @@ 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:
@@ -191,6 +197,7 @@ struct pstore_info {
struct mutex read_mutex;
int flags;
+ int max_reason;
void *data;
int (*open)(struct pstore_info *psi);
--
2.17.1
