> -----Original Message----- > From: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> > Sent: Tuesday, January 7, 2025 3:59 AM > To: Robert Joslyn <robert_joslyn@xxxxxxxxxx> > Cc: linux-kernel@xxxxxxxxxxxxxxx; linux-rt-users@xxxxxxxxxxxxxxx; > tglx@xxxxxxxxxxxxx; rostedt@xxxxxxxxxxx; Shrikanth Hegde > <sshegde@xxxxxxxxxxxxx> > Subject: Re: [PATCH] powerpc: Allow scheduling of IRQ with PREEMPT_RT > > [Caution - External] > > On 2025-01-07 12:56:08 [+0100], To Robert Joslyn wrote: > > On 2024-12-26 11:12:38 [-0800], Robert Joslyn wrote: > > > This branch is needed to allow preemptible IRQs to be scheduled, > > > otherwise the kernel hangs during boot on my e300 based platforms. > > > This branch is needed for both CONFIG_PREEMPT and > CONFIG_PREEMPT_RT, > > > so broaden the check to CONFIG_PREEMPTION, which is selected by both. > > > > > > This was previously set to CONFIG_PREEMPTION, but was reverted as > > > part of removing LAZY_PREEMPT support. > > > > I remember I pointed this out while Shrikanth posted the preempt-lazy > > patches but didn't realize that I need this in RT tree, too. > > > > The lazy-preempt patches for powerpc were merged upstream, I am going > > to pull them into the v6.6-series. > > I am going to Cc you, hopefully you can confirm that it is working. > > Robert, you are referring to v6.6-RT, correct? > > Sebastian Yes, I'm using 6.6.58-rt45 at the moment. We found this regression while trying to update from 5.10-rt. I haven't played with lazy-preempt yet but I can certainly test the patches, presently we run everything with PREEMPT_RT. Thanks, Robert
