Hi Ulf, Johan, ----- Original Message ----- > From: "Ulf Hansson" <ulf.hansson@xxxxxxxxxxxxxx> > To: linux-mmc@xxxxxxxxxxxxxxx, "Chris Ball" <cjb@xxxxxxxxxx> > Cc: "Per Forlin" <per.forlin@xxxxxxxxxxxxxx>, "Ulf Hansson" <ulf.hansson@xxxxxxxxxxxxxx>, "Lee Jones" > <lee.jones@xxxxxxxxxx>, "Johan Rudholm" <johan.rudholm@xxxxxxxxxxxxxx>, "John Beckett" <john.beckett@xxxxxxxxxxxxxx> > Sent: Friday, October 21, 2011 9:17:23 AM > Subject: [PATCH] mmc: boot partition ro lock support > > From: Johan Rudholm <johan.rudholm@xxxxxxxxxxxxxx> > > Enable boot partitions to be power and permanently read-only locked > via > a sysfs entry. There will be one sysfs entry for the main mmc device: > > /sys/block/mmcblkX/boot_partition_ro_lock > > and one for each boot partition: > > /sys/block/mmcblkXbootY/ro_lock > > The boot partitions are power or permanently locked by writing > "pwr_ro" > or "perm_ro" to one of the files. > > Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxxxxxx> > Signed-off-by: John Beckett <john.beckett@xxxxxxxxxxxxxx> > Signed-off-by: Johan Rudholm <johan.rudholm@xxxxxxxxxxxxxx> > --- What does power locking do that force_ro currently doesn't achieve? The permalocking brick-potential (more like paper-weight-potential) is IMO unacceptably high that something like this is just accessible via a sysfs attribute. This is exactly why the boot partitions were put under force_ro, so that some poor sap wouldn't end up nuking the boot partitions (with obvious consequences), and permalocking seems even nastier. At a bigger picture, I'm uncertain what the point of this is. It adds code complexity for, a generally rare and possibly self-destructive operation. This is like the GP partitioning support - it's a once-a-time (and unrecoverable) operation usually done at manufacturing (or initial provisioning time) that shouldn't be even exposed to the general purpose user. This would be a good use of that arbitrary-CMD ioctl interface John Calixto put in. Thanks, A -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
