On Thu, Sep 02, 2021 at 11:51:15PM +0200, Thomas Gleixner wrote: > Paul, > > On Wed, Aug 18 2021 at 10:56, Paul E. McKenney wrote: > > On Wed, Aug 18, 2021 at 02:02:17PM -0300, Fabio Estevam wrote: > >> On Wed, Aug 18, 2021 at 1:29 PM Fabio Estevam <festevam@xxxxxxxxx> wrote: > >> > On Wed, Aug 18, 2021 at 12:43 PM Paul E. McKenney <paulmck@xxxxxxxxxx> wrote: > >> > > >> > > I believe that you need this commit (and possibly some prerequsites): > >> > > > >> > > 47c218dcae65 ("tick/sched: Prevent false positive softirq pending warnings on RT") > >> > > > >> > > Adding Qais on CC for his thoughts. > >> > > >> > Thanks for the suggestion, but I am running 5.13.11, which already > >> > contains this commit. > >> > > >> > Any extra logs I should capture to help us understand the problem? > >> > >> In case it helps, I followed your suggestion from: > >> https://lkml.org/lkml/2020/12/10/676 > >> > >> With the debug patch and suggested command line, I get the following log: > >> https://pastebin.com/raw/X96zKw7i > > > > And it turns out that I am also seeing it in v5.14-rc2, just a lot less > > frequently than earlier. I have seen three instances of handler #02 > > (NET_TX_SOFTIRQ?) over the past month or so while you are seeing handler > > #08 (BLOCK_SOFTIRQ?), in case that makes a difference. > > Huch? #02 is TIMER_SOFTIRQ and #08 is NET_TX_SOFTIRQ. Idiot here was forgetting that the #02 represents bit 1 (as you say, TIMER_SOFTIRQ) rather than numeral 2. Ditto for the #08. :-/ Thanx, Paul