On Mon, 2020-11-02 at 00:29 -0700, Nathan Chancellor wrote: > Hi everyone, > > Starting with v5.10-rc1, I appear to be experiencing hard lockups on my > Raspberry Pi 4 when compiling LLVM. My standard workflow for testing the > Raspberry Pi 4 has been compiling tip of tree LLVM (to catch host > AArch64 issues), compiling linux-next ARCH=arm64 defconfig, then booting > it with QEMU + KVM, which has caught a few issues so far. Starting with > v5.10-rc1, compiling LLVM causes the serial console to print junk like > > |▒pp▒p▒p▒p > p|▒|▒|p▒p▒p|▒▒|▒|▒|p|▒▒|▒|▒| > p▒pp▒▒▒|▒▒ > ▒ > ▒|▒|▒▒▒▒ > p▒ > ▒ > ▒▒ > ▒ > ▒p|p > > then I lose my mosh connection and I see the lights on the front of the > Pi stop blinking. > > I have managed to narrow it down to a commit somewhere in the armsoc DT > merge. > > Good: 2e368dd2bbea ("Merge tag 'armsoc-drivers' of > git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc") > Bad: e533cda12d8f ("Merge tag 'armsoc-dt' of > git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc") > > I have not been able to complete a full bisect due to a lack of time > unfortunately, I am sending this email to hopefully get some more eyes > on the issue. > > $ head -n6 /boot/config.txt > # My settings > enable_uart=1 > core_freq_min=500 > kernel=Image > os_prefix=custom-mainline-gcc-arm64/ > upstream_kernel=1 > > $ cat /boot/.firmware_revision > e8ddac7cd34b179efd702d4dc1efd0ccf44559b9 > > I can reproduce the issue with: > > $ git clone --depth=1 https://github.com/llvm/llvm-project > > $ mkdir -p llvm-project/build && cd llvm-project/build > > $ cmake \ > -G Ninja \ > -DCMAKE_BUILD_TYPE=Release \ > -DLLVM_ENABLE_PROJECTS="clang;lld" \ > ../llvm && > ninja > > If you need any more information or testing, please let me know!
Thanks for the report! I'll have a look at it tomorrow. Regards, Nicolas
signature.asc
Description: This is a digitally signed message part