On Tue, 15 Mar 2011, Srikar Dronamraju wrote: > * Thomas Gleixner <tglx@xxxxxxxxxxxxx> [2011-03-15 14:22:09]: > > > On Mon, 14 Mar 2011, Srikar Dronamraju wrote: > > > +/* > > > + * Called with tsk->mm->mmap_sem held (either for read or write and > > > + * with a reference to tsk->mm > > > > Hmm, why is holding it for read sufficient? > > We are not adding a new vma to the mm; but just replacing a page with > another after holding the locks for the pages. Existing routines > doing close to similar things like the > access_process_vm/get_user_pages seem to be taking the read_lock. Do > you see a resaon why readlock wouldnt suffice? No, I just was confused by the comment. Probably should have asked why you want to call it write locked. Thanks, tglx -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>