Arnd Bergmann <arnd@xxxxxxxx> writes: > On Wed, May 13, 2020 at 2:57 PM Kalle Valo <kvalo@xxxxxxxxxxxxxx> wrote: >> >> Arnd Bergmann <arnd@xxxxxxxx> writes: >> >> > On Wed, May 13, 2020 at 8:50 AM Kalle Valo <kvalo@xxxxxxxxxxxxxx> wrote: >> >> >> >> Kalle Valo <kvalo@xxxxxxxxxxxxxx> writes: >> > >> > At least if it fails reproducibly, it's probably not too hard to drill >> > down further. Some ideas: >> > >> > * I'd first try to reproduce it in qemu. Since you don't even need >> > any user space or modules, I would simply try >> > $ qemu-system-x86_64 -nographic -monitor none -append >> > "console=ttyS0" -serial stdio -smp 4 -kernel arch/x86/boot/bzImage >> > I tried it here with an x86 defconfig linux-next kernel but did not >> > run into the problem you described. >> >> Thanks, I'll try that but I expect it will take few days before I can do >> it. >> >> > 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. >> > * There are still two prerelease compiler versions on kernel.org, >> > from February and from April. You can try each one to see >> > if this was a recent regression. It's also possible that there is >> > a problem with my specific builds of gcc-10.1, and that the >> > compiler is actually fine for others.The gcc-10 packages in >> > Fedora/Debian/Ubuntu are probably better tested. >> >> I'm still using Ubuntu 16.04 so not sure how easy it is to find a >> package for that, but maybe this is a good reason to finally my upgrade >> my laptop :) > > I checked with the gcc-10 package from Ubuntu 20.04, same > result as with my version, at least that indicates it's not my fault ;-) That's good to know as well. And now I can delay my laptop upgrade even more ;) -- https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
