Am 2014-10-19 02:31, schrieb Martin Kepplinger: > if we depend on private_data being NULL in write() before initialize() > make sure it is NULL after open(). > > Signed-off-by: Martin Kepplinger <mart...@posteo.de> > --- > > I'm not completely sure if this patch is needed and am still investigating. > What do you think? open() could be called by the user I guess. Does > lguest_user.c depend on private_data being NULL on a first write()? > >
Could it be that this patch is not needed indeed or did I ask not clear enough here and caused a misunderstanding: > Martin Kepplinger <mart...@posteo.de> writes: >> hi >> >> Just a question for understanding: open() is not implemented in >> lguest_user.c's miscdevice. The miscdevice core, in this case, does >> _not_ set file->private_data on a user's open() call. Is open() called >> by the user here? and do you here _depend_ on file->private_data being >> NULL after open()? (could you even?) >> >> Would the following force to NULL be necessary if the miscdevice core >> _would_ set private_data? > > Hi Martin! > > Yes, the private_data is NULL on a new file. See > get_empty_filp in fs/file_table.c, which does kmem_cache_zalloc > (zeroing all the contents). > > So this isn't necessary here. > > Thanks! > Rusty. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
