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. And looking at that ftrace output in the pastebin there is nothing which raises NET_TX_SOFTIRQ but then the warning claims it is pending. This does not make any sense at all. Thanks, tglx