On Thu, Feb 29, 2024 at 12:15:28PM +0100, Petr Mladek wrote: > On Thu 2024-02-22 00:21:19, John B. Wyatt IV wrote: > > On Mon, Feb 12, 2024 at 04:23:04PM -0500, John B. Wyatt IV wrote: > > > > I found 2 additional NMIs for a total of 3. Number 2 is very > > large-please feel free to let me know what specific information you > > wanted if it was unnecessary. > > > > This first one (the original) is with the real-time profile (no preemption). > > The next two are with the performance-througput (no preemption). > > > > This is what real-time NMI reports with the caller information enabled. It > > looks like it is lacking some information compared to the other two further below. > > > > [ T2481] Call Trace: > > [ T2477] Kernel panic - not syncing: sysrq triggered crash > > [ C0] NMI backtrace for cpu 0 > > This message seems to be printed by nmi_cpu_backtrace(). > > I am surprised. I would expect to see the backtrace printed from panic(). > It calls dump_stack() directly on the panic-CPU. And this panic() should > be called from sysrq_handle_crash(). IMHO, it should be (normal) > interrupt context. > > Is it different on RT? Yes. There are no NMIs on this machine in my tests for when I run an RT enabled kernel. > > Or have you somehow modified the kernel to use NMI for sysrq? > I have not modified the kernel source code from 6.7.0-rt6. -- Sincerly, John Wyatt Software Engineer, Core Kernel
