| Message ID | 20220425090841.3958494-1-atomlin@redhat.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | module: Introduce module unload taint tracking | expand |
On Mon, Apr 25, 2022 at 10:08:39AM +0100, Aaron Tomlin wrote: > Hi Luis, > > This iteration is still based on the latest mcgrof/modules-next branch. > > I have decided still to use RCU even though no entry is ever removed from > the unloaded tainted modules list. That being said, if I understand > correctly, it is not safe in some instances to use 'module_mutex' in > print_modules(). So instead we disable preemption to ensure list traversal > with concurrent list manipulation e.g. list_add_rcu(), is safe too. > > Changes since v3 [1] > - Fixed kernel build error reported by kernel test robot i.e. moved > '#endif' outside 'if (!list_empty(&unloaded_tainted_modules))' > statement in the context of print_modules() > - Used strncmp() instead of memcmp() > (Oleksandr Natalenko) > - Removed the additional strlen() > (Christoph Lameter) > > Changes since v2 [2] > - Dropped RFC from subject > - Removed the newline i.e. "\n" in printk() > - Always include the tainted module's unload count > - Unconditionally display each unloaded tainted module > > Please let me know your thoughts. This all looks good except with all the work you did to remove #ifdef hell, it gets me wondering why not just use a new file for this? What does that look like? Luis
On Mon 2022-04-25 16:31 -0700, Luis Chamberlain wrote: > This all looks good except with all the work you did to remove > #ifdef hell, it gets me wondering why not just use a new file for this? > > What does that look like? Hi Luis, I thought about it. It is indeed possible. Yet, I do not think it is worth it, for such a small change; albeit, what do you prefer? Kind regards,
On Tue, Apr 26, 2022 at 09:39:30AM +0100, Aaron Tomlin wrote: > On Mon 2022-04-25 16:31 -0700, Luis Chamberlain wrote: > > This all looks good except with all the work you did to remove > > #ifdef hell, it gets me wondering why not just use a new file for this? > > > > What does that look like? > > Hi Luis, > > I thought about it. It is indeed possible. Yet, I do not think it is worth > it, for such a small change; albeit, what do you prefer? I'd rather see the effort than not, given all the effort to already split things. I think it keeps things pretty tidy and it can scale / and its easier to review. Luis
On Tue 2022-04-26 09:22 -0700, Luis Chamberlain wrote: > I'd rather see the effort than not, given all the effort to already split things. > I think it keeps things pretty tidy and it can scale / and its easier to review. Fair enough. I'll create another iteration of the series.
Hi Luis, This iteration is still based on the latest mcgrof/modules-next branch. I have decided still to use RCU even though no entry is ever removed from the unloaded tainted modules list. That being said, if I understand correctly, it is not safe in some instances to use 'module_mutex' in print_modules(). So instead we disable preemption to ensure list traversal with concurrent list manipulation e.g. list_add_rcu(), is safe too. Changes since v3 [1] - Fixed kernel build error reported by kernel test robot i.e. moved '#endif' outside 'if (!list_empty(&unloaded_tainted_modules))' statement in the context of print_modules() - Used strncmp() instead of memcmp() (Oleksandr Natalenko) - Removed the additional strlen() (Christoph Lameter) Changes since v2 [2] - Dropped RFC from subject - Removed the newline i.e. "\n" in printk() - Always include the tainted module's unload count - Unconditionally display each unloaded tainted module Please let me know your thoughts. [1]: https://lore.kernel.org/all/20220420115257.3498300-1-atomlin@redhat.com/ [2]: https://lore.kernel.org/all/20220419150334.3395019-1-atomlin@redhat.com/ Aaron Tomlin (2): module: Make module_flags_taint() accept a module's taints bitmap directly module: Introduce module unload taint tracking init/Kconfig | 11 +++++++ kernel/module/main.c | 73 +++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 80 insertions(+), 4 deletions(-) base-commit: eeaec7801c421e17edda6e45a32d4a5596b633da