Why should we need to log to block (mtd) device? 1. Most embedded intelligent equipment have no persistent ram, which increases costs. We perfer to cheaper solutions, like block devices. 2. Do not any equipment have battery, which means that it lost all data on general ram if power failure. Pstore has little to do for these equipments. Why should we adapt pstore/blk to MTD device instead of mtdoops? 1. repetitive jobs between pstore and mtdoops Both of pstore and mtdoops do the same jobs that store panic/oops log. 2. do what a driver should do To me, a driver should provide methods instead of policies. What MTD should do is to provide read/write/erase operations, geting rid of codes about chunk management, kmsg dumper and configuration. 3. enhanced feature Not only store log, but also show it as files. Not only log, but also trigger time and trigger count. Not only panic/oops log, but also log recorder for pmsg, console and ftrace in the future. Before upstream submission, pstore/blk is tested on arch ARM and x84_64, block device and mtd device, built as modules and in kernel. Here are the details: https://github.com/gmpy/articles/blob/master/pstore/Test-Pstore-Block.md WeiXiong Liao (11): pstore/blk: new support logger for block devices blkoops: add blkoops, a warpper for pstore/blk pstore/blk: support pmsg recorder pstore/blk: blkoops: support console recorder pstore/blk: blkoops: support ftrace recorder Documentation: pstore/blk: blkoops: create document for pstore_blk pstore/blk: skip broken zone for mtd device blkoops: respect for device to pick recorders pstore/blk: blkoops: support special removing jobs for dmesg. blkoops: add interface for dirver to get information of blkoops mtd: new support oops logger based on pstore/blk Documentation/admin-guide/pstore-block.rst | 297 ++++++ MAINTAINERS | 3 +- drivers/mtd/Kconfig | 10 + drivers/mtd/Makefile | 1 + drivers/mtd/mtdpstore.c | 531 +++++++++++ fs/pstore/Kconfig | 109 +++ fs/pstore/Makefile | 5 + fs/pstore/blkoops.c | 490 ++++++++++ fs/pstore/blkzone.c | 1341 ++++++++++++++++++++++++++++ include/linux/blkoops.h | 94 ++ include/linux/pstore_blk.h | 91 ++ 11 files changed, 2971 insertions(+), 1 deletion(-) create mode 100644 Documentation/admin-guide/pstore-block.rst create mode 100644 drivers/mtd/mtdpstore.c create mode 100644 fs/pstore/blkoops.c create mode 100644 fs/pstore/blkzone.c create mode 100644 include/linux/blkoops.h create mode 100644 include/linux/pstore_blk.h -- 1.9.1
