On Thu, Nov 30, 2023 at 12:08 AM Ronald Monthero <debug.penguin32@xxxxxxxxx> wrote: > > On Sat, Nov 25, 2023 at 2:10 AM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > > On Tue, Nov 21, 2023 at 12:09:38AM +1000, Ronald Monthero wrote: > > > Dear stable maintainers, > > > I like to indicate the oops encountered and request the below patch to > > > be backported to v 5.15. The fix is important to avoid recurring oops > > > in context of rcu detected stalls. > > > > > > subject: rcu: Avoid tracing a few functions executed in stop machine > > > commit 48f8070f5dd8 > > > Target kernel version v 5.15 > > > Reason for Application: To avoid oops due to rcu_prempt detect stalls > > > on cpus/tasks > > > > > > Environment and oops context: Issue was observed in my environment on > > > 5.15.193 kernel (arm platform). The patch is helpful to avoid the > > > below oops indicated in [1] and [2] > > > > As the patch does not apply cleanly, we need a working and tested > > backport so we know to apply the correct version. > > > > Can you please provide that as you've obviously already done this? > > Hi Greg, > Sorry I notice my typo error 193 instead of 93. I have tested on the > 5.15.93-rt58 kernel. Hi Greg, I used a 5.15.93 kernel - on arm32 bit platform I tested with 5.15.93-rt58 (rt kernel) , on real hardware - Freescale LS1021A, 32 bit Cortex A7 processor - on x86_64 platform I tested non rt kernel 5.15.93 - virtual machine - qemu platform Below is the build log after patch to kernel/rcu/tree.h on x86_64 linux-5.15.93$ make CALL scripts/checksyscalls.sh CALL scripts/atomic/check-atomics.sh DESCEND objtool DESCEND bpf/resolve_btfids CHK include/generated/compile.h CC kernel/rcu/tree.o <<< AR kernel/rcu/built-in.a <<< AR kernel/built-in.a CHK kernel/kheaders_data.tar.xz GEN .version CHK include/generated/compile.h UPD include/generated/compile.h CC init/version.o AR init/built-in.a LD vmlinux.o MODPOST vmlinux.symvers MODINFO modules.builtin.modinfo GEN modules.builtin LD .tmp_vmlinux.btf BTF .btf.vmlinux.bin.o LD .tmp_vmlinux.kallsyms1 < snipped > BTF [M] sound/usb/usx2y/snd-usb-usx2y.ko BTF [M] sound/virtio/virtio_snd.ko BTF [M] sound/x86/snd-hdmi-lpe-audio.ko BTF [M] sound/xen/snd_xen_front.ko BTF [M] virt/lib/irqbypass.ko linux-5.15.93$ BR, ronald