Re: [PATCH v4 0/8] Nvram-to-pstore

[Aruna Balakrishnaiah]

Hi Michael,

On Wednesday 19 June 2013 11:45 AM, Michael Neuling wrote:
> Aruna Balakrishnaiah <aruna@xxxxxxxxxxxxxxxxxx> wrote:
> > Currently the kernel provides the contents of p-series NVRAM only as a
> > simple stream of bytes via /dev/nvram, which must be interpreted in user
> > space by the nvram command in the powerpc-utils package. This patch set
> > exploits the pstore subsystem to expose each partition in NVRAM as a
> > separate file in /dev/pstore. For instance, Oops messages will be stored
> > in a file named [dmesg-nvram-2].
> >
> > Changes from v3:
> > 	- Change filename prefix for of-config and common partition
> >
> > Changes from v2:
> > 	- Fix renaming of pstore type ids in nvram.c
> >
> > Changes from v1:
> > 	- Reduce #ifdefs by and remove forward declarations of pstore callbacks
> > 	- Handle return value of nvram_write_os_partition
> > 	- Remove empty pstore callbacks and register pstore only when pstore
> > 	  is configured
> When booted on pHyp, I see /dev/nvram but not /dev/pstore, even if I
> turn on CONFIG_PSTORE.  Is there something else I need to add?

You need to mount pstore to access the files.

# mkdir /dev/pstore
# mount -t pstore - /dev/pstore

to unmount

# umount /dev/pstore

References: http://lwn.net/Articles/421297/
Documentation/ABI/testing/pstore

> Should we update pseries_defconfig to include CONFIG_PSTORE (which it
> doesn't include currently)?  Maybe turn on panic/oops via
> CONFIG_PSTORE_RAM too?

Yes. We should enable CONFIG_PSTORE by default in pseries_defconfig.
We need not enable CONFIG_PSTORE_RAM for our case. Its for systems with
persistent RAM.

> Other than that, the series looks clean.  It's passes my build and boot
> tests.
>
> I've not reviewed the contents of the patches.
>
> Mikey
>
> > ---
> >
> > Aruna Balakrishnaiah (8):
> >        powerpc/pseries: Remove syslog prefix in uncompressed oops text
> >        powerpc/pseries: Add version and timestamp to oops header
> >        powerpc/pseries: Introduce generic read function to read nvram-partitions
> >        powerpc/pseries: Read/Write oops nvram partition via pstore
> >        powerpc/pseries: Read rtas partition via pstore
> >        powerpc/pseries: Distinguish between a os-partition and non-os partition
> >        powerpc/pseries: Read of-config partition via pstore
> >        powerpc/pseries: Read common partition via pstore
> >
> >
> >   arch/powerpc/platforms/pseries/nvram.c |  353 +++++++++++++++++++++++++++-----
> >   fs/pstore/inode.c                      |    9 +
> >   include/linux/pstore.h                 |    4
> >   3 files changed, 313 insertions(+), 53 deletions(-)
> >
> > --
> >
> > _______________________________________________
> > Linuxppc-dev mailing list
> > Linuxppc-dev@xxxxxxxxxxxxxxxx
> > https://lists.ozlabs.org/listinfo/linuxppc-dev
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev@xxxxxxxxxxxxxxxx
> https://lists.ozlabs.org/listinfo/linuxppc-dev

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/