Il 02/05/2012 15:51, Jan Kara ha scritto: >> > NACK. I would bet that all the warnings you've seen are for ioctl that >> > would have failed anyway with ENOTTY. > Actually, you would loose the bet ;) Doh. :) > The customer was complaining about > warning about SG_IO ioctl. Apparently some Veritas filesystem thread generates > a *lot* of these (I don't know if they happen to do all the filesystem IO > with SG_IO and I'm not sure I want to know ;). Can you at least ask the customer for help finding which command was sent? And perhaps have them try a kernel that blocks SG_IO to see what breaks if anything? > Also I tend to side with Alan that I don't quite see > the point in trying to restrict CAP_SYS_RAWIO threads and thus breaking the > compatibility For example, we have a customer that wants this: * a VM should be able to send vendor-specific commands to a disk via SG_IO (vendor-specific commands require CAP_SYS_RAWIO). * they want to assign logical volumes or partitions to the same VM without letting it read or write outside the logical volume or partition. Of course a better solution for this would be customizable filters for SG_IO commands, where a privileged application would open the block device with CAP_SYS_RAWIO, set the filter and hand the file descriptor to QEMU. Or alternatively some extension of the device cgroup. But either solution would require a large amount of work. Paolo > (if ioctls would be restricted for partitions from the > beginning, then sure it seems like a cleaner choice). But I don't feel that > strongly about it. -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
