On Thu, 29 Nov 2018, Petr Mladek wrote: > The atomic replace and cumulative patches were introduced as a more secure > way to handle dependent patches. They simplify the logic: > > + Any new cumulative patch is supposed to take over shadow variables > and changes made by callbacks from previous livepatches. > > + All replaced patches are discarded and the modules can be unloaded. > As a result, there is only one scenario when a cumulative livepatch > gets disabled. > > The different handling of "normal" and cumulative patches might cause > confusion. It would make sense to keep only one mode. On the other hand, > it would be rude to enforce using the cumulative livepatches even for > trivial and independent (hot) fixes. > > This patch removes the stack of patches. The list of enabled patches > is still needed but the ordering is not longer enforced. > > Note that it is not possible to catch all possible dependencies. It is > the responsibility of the livepatch authors to decide. > > Nevertheless this patch prevents having two patches for the same function > enabled at the same time after the transition finishes. It might help > to catch obvious mistakes. But more importantly, we do not need to > handle situation when a patch in the middle of the function stack > (ops->func_stack) is being removed. > > Signed-off-by: Petr Mladek <pmladek@xxxxxxxx> Acked-by: Miroslav Benes <mbenes@xxxxxxx> M
