Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762037Ab2KCAD4 (ORCPT ); Fri, 2 Nov 2012 20:03:56 -0400 Received: from mail-pa0-f46.google.com ([209.85.220.46]:59517 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761912Ab2KCADx (ORCPT ); Fri, 2 Nov 2012 20:03:53 -0400 MIME-Version: 1.0 In-Reply-To: References: From: Mike Waychison Date: Fri, 2 Nov 2012 17:03:32 -0700 Message-ID: Subject: Re: [RESEND][PATCH v4 0/7] efi_pstore: multiple event logging support To: Seiji Aguchi Cc: "linux-kernel@vger.kernel.org" , "linux-efi@vger.kernel.org" , "linux-acpi@vger.kernel.org" , "Luck, Tony (tony.luck@intel.com)" , "Matthew Garrett (mjg@redhat.com)" , "dzickus@redhat.com" , "dle-develop@lists.sourceforge.net" , Satoru Moriya Content-Type: text/plain; charset=ISO-8859-1 X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3314 Lines: 79 Series Acked-by: Mike Waychison Tony: Did you want to pull this? On Thu, Nov 1, 2012 at 3:59 PM, Seiji Aguchi wrote: > Changelog > > v3 -> v4 > - Rebase to 3.7-rc3 > - Add ctime to an argument of efi_pstore_erase to build successfully > in case where CONFIG_PTORE=n is specified. (Patch 4/7) > - Add count to an argument of efi_pstore_erase and efi_pstore_write to > build successfully in case where CONFIG_PTORE=n is specified (Patch 5/7) > - Fix a white space damage (Patch 6/7) > - Modify a logic checking a 3-variable format of a variable name (Patch 7/7) > > v2 -> v3 > - Create patches 6/7 and 7/7 to work with an existing format of variable name > > v1 -> v2 > - Separate into 5 patches in accordance with Mike's comment > - Erase an extra line of comment in patch 1/5 > > [Issue] > > Currently, efi_pstore driver simply overwrites existing panic messages in NVRAM. > So, in the following scenario, we will lose 1st panic messages. > > 1. kernel panics. > 2. efi_pstore is kicked and writes panic messages to NVRAM. > 3. system reboots. > 4. kernel panics again before a user checks the 1st panic messages in NVRAM. > > [Solution] > > Solutions of this problem has been discussed among Tony, Matthew, Don, Mike and me. > > http://marc.info/?l=linux-kernel&m=134273270704586&w=2 > > And there are two possible solutions right now. > - First one is introducing some policy overwriting existing logs. > - Second one is simply holding multiple log without overwriting any entries. > > We haven't decided the overwriting policy which is reasonable to all users yet. > But I believe we agree that just holding multiple logs is a reasonable way. > > We may need further discussions to find the possibility of introducing overwriting > policy, especially getting critical messages in multiple oops case. > But I would like to begin with a simple and reasonable way to everyone. > So, this patch takes an approach just holding multiple logs. > > [Patch Description] > > Seiji Aguchi (7): > efi_pstore: Check remaining space with QueryVariableInfo() before > writing data > efi_pstore: Add a logic erasing entries to an erase callback > efi_pstore: Remove a logic erasing entries from a write callback to > hold multiple logs > efi_pstore: Add ctime to argument of erase callback > efi_pstore: Add a sequence counter to a variable name > efi_pstore: Add a format check for an existing variable name at > reading time > Add a format check for an existing variable name at erasing time > > drivers/acpi/apei/erst.c | 16 ++-- > drivers/firmware/efivars.c | 163 ++++++++++++++++++++++++++++++------------- > fs/pstore/inode.c | 7 ++- > fs/pstore/internal.h | 2 +- > fs/pstore/platform.c | 11 ++-- > fs/pstore/ram.c | 9 +-- > include/linux/efi.h | 1 + > include/linux/pstore.h | 6 +- > 8 files changed, 143 insertions(+), 72 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/