12 Oct
2021
12 Oct
'21
1:58 a.m.
From: Vasile-Laurentiu Stanimir <vasile-laurentiu.stanimir(a)windriver.com>
mainline inclusion
from mainline-5.10
category: feature
commit:26fecbf7602dd69b649914e61526bd67c557fece
issue: #I4919J
--------------------------------
While kmsg_bytes can be set for pstore via mount, if a crash occurs
before the mount only partial console log will be stored as kmsg_bytes
defaults to a potentially different hardcoded value in the kernel
(PSTORE_DEFAULT_KMSG_BYTES). This makes it impossible to analyze valuable
post-mortem data especially on the embedded development or in the process
of bringing up new boards. Change this value to be a Kconfig option
with the default of old PSTORE_DEFAULT_KMSG_BYTES
Signed-off-by: Vasile-Laurentiu Stanimir <vasile-laurentiu.stanimir(a)windriver.com>
Signed-off-by: Kees Cook <keescook(a)chromium.org>
(cherry picked from commit 26fecbf7602dd69b649914e61526bd67c557fece)
Signed-off-by: roger <kongzhengrong(a)huawei.com>
---
fs/pstore/Kconfig | 8 ++++++++
fs/pstore/inode.c | 2 +-
fs/pstore/internal.h | 1 -
fs/pstore/platform.c | 2 +-
4 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/fs/pstore/Kconfig b/fs/pstore/Kconfig
index 0f5a4bdb3b34..e0ac6601a928 100644
--- a/fs/pstore/Kconfig
+++ b/fs/pstore/Kconfig
@@ -13,6 +13,14 @@ config PSTORE
If you don't have a platform persistent store driver,
say N.
+config PSTORE_DEFAULT_KMSG_BYTES
+ int "Default kernel log storage space" if EXPERT
+ depends on PSTORE
+ default "10240"
+ help
+ Defines default size of pstore kernel log storage.
+ Can be enlarged if needed, not recommended to shrink it.
+
config PSTORE_DEFLATE_COMPRESS
tristate "DEFLATE (ZLIB) compression"
default y
diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index c29e4d4a3359..b4836705d220 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -276,7 +276,7 @@ static void parse_options(char *options)
*/
static int pstore_show_options(struct seq_file *m, struct dentry *root)
{
- if (kmsg_bytes != PSTORE_DEFAULT_KMSG_BYTES)
+ if (kmsg_bytes != CONFIG_PSTORE_DEFAULT_KMSG_BYTES)
seq_printf(m, ",kmsg_bytes=%lu", kmsg_bytes);
return 0;
}
diff --git a/fs/pstore/internal.h b/fs/pstore/internal.h
index 7783db28ce4a..b82e074853ec 100644
--- a/fs/pstore/internal.h
+++ b/fs/pstore/internal.h
@@ -6,7 +6,6 @@
#include <linux/time.h>
#include <linux/pstore.h>
-#define PSTORE_DEFAULT_KMSG_BYTES 10240
extern unsigned long kmsg_bytes;
#ifdef CONFIG_PSTORE_FTRACE
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 216c3247a2c6..b0703d0278b4 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -112,7 +112,7 @@ static char *big_oops_buf;
static size_t big_oops_buf_sz;
/* How much of the console log to snapshot */
-unsigned long kmsg_bytes = PSTORE_DEFAULT_KMSG_BYTES;
+unsigned long kmsg_bytes = CONFIG_PSTORE_DEFAULT_KMSG_BYTES;
void pstore_set_kmsg_bytes(int bytes)
{
--
2.17.1