On 2022-06-24 11:10:55 [+0200], Marco Elver wrote: > On Fri, 24 Jun 2022 at 11:05, Sebastian Andrzej Siewior > <bigeasy@xxxxxxxxxxxxx> wrote: > > > > On 2022-06-18 11:34:51 [+0200], Mike Galbraith wrote: > > > I moved the prandom_u32_max() call in kfence_guarded_alloc() out from > > > under raw spinlock to shut this one up. > > > > Care to send a patch? I don't even why kfence_metadata::lock is a > > raw_spinlock_t. This is the case since the beginning of the code. > > Because kfence_handle_page_fault() may be called from anywhere, incl. > other raw_spinlock critical sections. We have this problem with all > debugging tools where the bug may manifest anywhere. Oh thank you. I had some vague memory of this but could find anything. > A patch for it already exists in -mm: > https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git/commit/?h=mm-hotfixes-stable&id=327b18b7aaed5de3b548212e3ab75133bf323759 Thanks for the pointer. Sebastian
