On Wed, May 13, 2020 at 5:31 PM Kalle Valo <kvalo@xxxxxxxxxxxxxx> wrote: > Arnd Bergmann <arnd@xxxxxxxx> writes: > > On Wed, May 13, 2020 at 2:57 PM Kalle Valo <kvalo@xxxxxxxxxxxxxx> wrote: > >> > >> Arnd Bergmann <arnd@xxxxxxxx> writes: > >> > >> > If you share your .config, I can try reproducing with that as well. > >> > Once there is a reproducer in qemu, it should be trivial to step > >> > through it using gdb. > >> > >> I have attached the .config I used with GCC 10.1. If you are able to > >> test it please do let me know how it went. > > > > Yes, I see the same problem now, but have not investigated > > any further. > > Great, so it's not a problem due to my setup. I investigated a little more: This does happen with 'defconfig' after all, in my first try I must have missed the '-smp 2' argument to qemu, and it ended up working correctly with just one CPU but fails now. Stepping through the boot process, I see where it crashes in start_secondary: | /* to prevent fake stack check failure in clock setup */ | boot_init_stack_canary(); | | x86_cpuinit.setup_percpu_clockev(); | | wmb(); | cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); The call to cpu_startup_entry() does not succeed, instead it jumps to __stack_chk_fail() from there. Arnd