[Dle-develop] [RFC][PATCH 0/2]efi_pstore: Avoid missing panic message in NVRAM

[Seiji A. <sei...@hd...>]

[Problem]
Current efi_pstore simply overwrites existing entries in NVRAM.
So, if 2nd panic happens before a user checks 1st panic message, 1st panic message will be lost.

[Solution]
To avoid missing 1st panic message, this patch introduce a rule checking if existing entries in NRAM are erasable to efi_pstore.
 
[Patch Descriptions]
 
 [PATCH 1/2] Duplicate a shared code between write and erase callbacks  
 
  Currently, efi_pstore driver shares a code erasing existing entries in NVRAM with write and erase callbacks.
  But there some cases we should avoid erasing existing entries in write callback. (Please see PATCH 2/2).
  This patch duplicates the code so that write and erase callbacks work independently. 
 
 
 [PATCH 2/2] write callback: Check if existing entry is erasable
 
  this patch introduce a rule checking if existing entries in NRAM are erasable to efi_pstore.
  With this patch, if previous event is panic, efi_pstore never overwrite it.

 
  drivers/firmware/efivars.c |   94 +++++++++++++++++++++++++++++++++++++++++++-
  fs/pstore/platform.c       |    4 +-
  include/linux/pstore.h     |    5 ++
  3 files changed, 99 insertions(+), 4 deletions(-)
 
 Seiji