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| author | WeiXiong Liao <liaoweixiong@allwinnertech.com> | 2020-03-25 11:55:06 +0300 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2020-06-01 05:49:01 +0300 |
| commit | 78c08247b9d3e03192f8b359aa079024e805a948 (patch) | |
| tree | ebc4c79461299d67d159c672c86b52e6b6c8acc7 /Documentation | |
| parent | f8feafeaeedbf0a324c373c5fa29a2098a69c458 (diff) | |
| download | linux-78c08247b9d3e03192f8b359aa079024e805a948.tar.xz | |
mtd: Support kmsg dumper based on pstore/blk
This introduces mtdpstore, which is similar to mtdoops but more
powerful. It uses pstore/blk, and aims to store panic and oops logs to
a flash partition, where pstore can later read back and present as files
in the mounted pstore filesystem.
To make mtdpstore work, the "blkdev" of pstore/blk should be set
as MTD device name or MTD device number. For more details, see
Documentation/admin-guide/pstore-blk.rst
This solves a number of issues:
- Work duplication: both of pstore and mtdoops do the same job storing
panic/oops log. They have very similar logic, registering to kmsg
dumper and storing logs to several chunks one by one.
- Layer violations: drivers should provides methods instead of polices.
MTD should provide read/write/erase operations, and allow a higher
level drivers to provide the chunk management, kmsg dump
configuration, etc.
- Missing features: pstore provides many additional features, including
presenting the logs as files, logging dump time and count, and
supporting other frontends like pmsg, console, etc.
Signed-off-by: WeiXiong Liao <liaoweixiong@allwinnertech.com>
Link: https://lore.kernel.org/lkml/20200511233229.27745-11-keescook@chromium.org/
Link: https://lore.kernel.org/r/1589266715-4168-1-git-send-email-liaoweixiong@allwinnertech.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/admin-guide/pstore-blk.rst | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/Documentation/admin-guide/pstore-blk.rst b/Documentation/admin-guide/pstore-blk.rst index d45341e55e82..296d5027787a 100644 --- a/Documentation/admin-guide/pstore-blk.rst +++ b/Documentation/admin-guide/pstore-blk.rst @@ -43,9 +43,9 @@ blkdev ~~~~~~ The block device to use. Most of the time, it is a partition of block device. -It's required for pstore/blk. +It's required for pstore/blk. It is also used for MTD device. -It accepts the following variants: +It accepts the following variants for block device: 1. <hex_major><hex_minor> device number in hexadecimal represents itself; no leading 0x, for example b302. @@ -64,6 +64,11 @@ It accepts the following variants: partition with a known unique id. #. <major>:<minor> major and minor number of the device separated by a colon. +It accepts the following variants for MTD device: + +1. <device name> MTD device name. "pstore" is recommended. +#. <device number> MTD device number. + kmsg_size ~~~~~~~~~ |