On 03/21/2012 08:35 AM, Greg KH wrote: > On Tue, Mar 20, 2012 at 04:18:49PM -0700, Boaz Harrosh wrote: >> Andrew Hi >> >> I'm picking on you because I don't have any one else to pick on. >> The 3 first patches here, are just good for today. Please see if >> you would like to take them? or tell me who should take them? >> >> The 4th patch is an RFC, which got me looking into this. >> >> My motivation is that I added yet another Kernel dependency on the >> call_usermodehelper() function and am not completely happy with the >> error case of having the user-mode program stuck forever. In such >> case I would like the Kernel part to timeout and properly error recover >> and clean up. So therefor the proposed 4th patch. > > What is this new use of call_usermodhelper that you are doing this work > for? Ideally, you never want to make this call, as it's slow and messy, > as you have found out. Is there an in-kernel user that you have > recently added? > > thanks, > > greg k-h I agree hence my comment in the 4th patch: "In the blasphemous occasions that a the Kernel must call a user-mode program" I have added a new caller, to the nfs/objectlayoutdriver.ko that uses this facility for auto-login into osd-targets (iscsi-targets) when new are requested by the filesystem. This auto-login facility is mandated by the pnfs-objects standard because in a large cluster filesystems for which pnfs was invented, storage devices break and changed everyday, and a manual login by every client is not feasible. You can see this patch as posted to the mailing list here: http://article.gmane.org/gmane.linux.nfs/48024/match=login [title: pnfs-obj: autologin: Add support for protocol autologin] It works very well and was heavily tested, with all error scenarios, but the theoretical possibility that the user-mode program can be stuck forever bothers me and I would like to do something about it. With this patch the Kernel can recover cleanly and continue. I have actually tested this part and it works as expected. Thanks Boaz -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
