On Mon, Sep 8, 2025 at 3:42 PM Peilin Ye <yepeilin@xxxxxxxxxx> wrote: > > Hi all, > > > > > [ 35.955287] BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 > > FWIW, I was able to reproduce this pr_err() after enabling > CONFIG_PREEMPT_RT and CONFIG_DEBUG_ATOMIC_SLEEP. > > On Mon, Sep 08, 2025 at 12:29:42PM -0700, Eduard Zingerman wrote: > > On Mon, 2025-09-08 at 12:20 -0700, Eduard Zingerman wrote: > > > On Mon, 2025-09-08 at 12:40 +0800, Leon Hwang wrote: > > > > When enable CONFIG_PREEMPT_RT, the kernel will panic when run timer > > > > selftests by './test_progs -t timer': > > > > Related discussions: > > [1] > > - https://lore.kernel.org/bpf/b634rejnvxqu6knjqlijosxrcnxbbpagt4de4pl6env6dwldz2@hoofqufparh5/T/ > > - https://lore.kernel.org/bpf/lhmdi6npaxqeuaumjhmq24ckpul7ufopwzxjbsezhepguqkxag@wolz4r2fazu2/T/ > > [...] > > > > The error is reported because of the kmalloc call in the __bpf_async_init, right? > > > Instead of disabling timers for PREEMPT_RT, would it be possible to > > > switch implementation to use kernel/bpf/memalloc.c:bpf_mem_alloc() instead? > > Just in case - actually there was a patch that does this: > > [2] https://lore.kernel.org/bpf/20250905061919.439648-1-yepeilin@xxxxxxxxxx/ Though switch to bpf_mem_alloc() kinda fixes it, it's too late for this release and it's not a complete fix for RT, so I think it's better to disable it in the verifier like this patch does. Leon, pls respin targeting bpf tree. Also trim the commit log. It's too verbose and not quite correct. "kernel will panic" That's true only if you have panic-on-warn set. Just say that the kernel will warn. pw-bot: cr
