On Mon, Mar 04, 2024 at 09:40:35AM -0800, Bart Van Assche wrote: > On 3/4/24 09:31, Benjamin LaHaise wrote: > >A revert is justified when a series of patches is buggy and had > >insufficient review prior to merging. > > That's not how Linux kernel development works. If a bug can get fixed > easily, a fix is preferred instead of reverting + reapplying a patch. Your original "fix" is not right, and it wasn't properly tested. Commit 54cbc058d86beca3515c994039b5c0f0a34f53dd needs to be reverted. > >Using the "a kernel warning hit" approach for work on cancellation is > >very much a sign that the patches were half baked. > Is there perhaps a misunderstanding? My patches fix a kernel warning and > did not introduce any new WARN*() statements. The change that introduced that callback by you was incorrect and should be reverted. > >Why are you touching the kiocb after ownership has already been > >passed on to another entity? > Touching the kiocb after ownership has been passed is the result of an > oversight. Whether or not kiocb->ki_cancel() transfers ownership depends > on the I/O type. The use-after-free was not introduced on purpose. Your fix is still incorrect. You're still touching memory that you don't own. The event should be generated via the ->ki_cancel method, not in the io_cancel() syscall. -ben > Bart. > > -- "Thought is the essence of where you are now."
