On Wed, 31 Mar 2021 at 16:51, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > On Wed, Mar 31, 2021 at 02:32:58PM +0200, Marco Elver wrote: > > On Mon, 29 Mar 2021 at 14:07, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > > > > > (and we might already have a problem on some architectures where there > > > can be significant time between these due to not having > > > arch_irq_work_raise(), so ideally we ought to double check current in > > > your case) > > > > I missed this bit -- just to verify: here we want to check that > > event->ctx->task == current, in case the the irq_work runs when the > > current task has already been replaced. Correct? > > Yeah, just not sure what a decent failure would be, silent ignore seems > undesired, maybe WARN and archs that can trigger it get to fix it ? I'll go with a WARN and add a comment. This also revealed there should be a requirement that sigtrap events must be associated with a task (syzkaller managed to trigger the warning for cpu events). Thanks, -- Marco
