Hi, On Thu, Oct 11, 2012 at 12:02 AM, Rusty Russell <rusty@xxxxxxxxxxxxxxx> wrote: > "Michael Kerrisk (man-pages)" <mtk.manpages@xxxxxxxxx> writes: > >> Hello Kees, Rusty, >> >> The current delete_module(2) page is severely out of date (basically, >> its content corresponds to 2.4 days, and was even pretty thin in >> covering that). So, I took a shot at revising the page to Linux 2.6+ >> reality. Would it be possible that you could review it? > > OK. Main suggestion is that I discussed with Lucas removing the > !O_NONBLOCK case. It's not supported by modprobe -r, and almost > unheard-of for rmmod (it's --wait). > > In practice, people want the unload-or-fail semantics, or the > force-unload semantics. I'm all for removing this option. My idea was to complain loudly if user tries to use it: http://git.kernel.org/?p=utils/kernel/kmod/kmod.git;a=commit;h=8447b865aaac9139485dccdcc576725ddec2e7fa But maybe it's good to just remove it altogether > >> Otherwise, by default, >> .BR delete_module () >> marks a module so that no new references are permitted. >> If the module's reference count >> (i.e., the number of processes currently using the module) is nonzero, >> it then places the caller in an uninterruptible sleep >> state until all reference count is zero, >> at which point the call unblocks. >> When the reference count reaches zero, the module is unloaded. > > So this should be inverted: > > Otherwise (assuming O_NONBLOCK, see flags below), if the > module's reference count (i.e., the number of processes > currently using the module) is nonzero, the call fails. > >> The >> .IR flags >> argument can be used to modify the behavior of the system call. > > It is usually set to O_NONBLOCK, which may be required in future kernel > versions (see NOTES). > >> The following values can be ORed in this argument: >> .TP >> .B O_TRUNC >> .\" KMOD_REMOVE_FORCE in kmod library >> Force unloading of the module, even if the following conditions are true: >> .RS >> .IP * 3 >> The module has no >> .I exit >> function. >> By default, attempting to unload a module that has no >> .I exit >> function fails. >> .IP * >> The reference count for (i.e., the number of processes currently using) >> this module is nonzero. > ... >> .IP >> Using this flag taints the kernel (TAINT_FORCED_RMMOD). >> .IP >> .IR "Using this flag is dangerous!" >> If the kernel was not built with >> .BR CONFIG_MODULE_FORCE_UNLOAD , >> this flag is silently ignored. > > NOTES: > > If O_NONBLOCK is not set, then the kernel may enter uninterruptible > sleep until the module reference count reaches zero. This is not > generally desirable, so this flag may be compulsory in future kernel > configurations. What do you think? Mark as deprecated now and remove when kernel removes it? Or remove now? Lucas De Marchi -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
