On Fri, Oct 16, 2020 at 4:18 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > > On 10/16/20 4:11 PM, Nick Desaulniers wrote: > > Hello all, > > I'm working on integrating the latest release of buildroot (2020.08.1) > > into our CI for ClangBuiltLinux. > > > > https://github.com/ClangBuiltLinux/boot-utils/pull/25 > > https://github.com/ClangBuiltLinux/boot-utils/pull/26 > > https://github.com/ClangBuiltLinux/continuous-integration/pull/327 > > > > I'm seeing the following error from QEMU: > > KASLR disabled: CPU has no PRNG > > Linux version 5.9.0-00732-g04ed4527465f (ndesaulniers@<myhost>) #30 > > SMP Fri Oct 16 15:49:05 PDT 2020Kernel fault: interruption code 0005 > > ilc:2 > > PSW : 0000200180000000 000000000001779e > > R:0 T:0 IO:0 EX:0 Key:0 M:0 W:0 P:0 AS:0 CC:2 PM:0 RI:0 EA:3 > > GPRS: 0000000000000001 0000000c00000000 00000003fffffff4 00000000fffffff0 > > 0000000000000000 00000000fffffff4 000000000000000c 00000000fffffff0 > > 00000000fffffffc 0000000000000000 00000000fffffff8 00000000008a75a8 > > 0000000000000009 0000000000000002 0000000000000008 000000000000bce0 > > > > This is via a kernel built by: > > $ ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- make CC=clang -j71 defconfig > > $ ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- make CC=clang -j71 > > > > The booting qemu: > > $ qemu-system-s390x -M s390-ccw-virtio -append 'rdinit=/bin/sh ' > > -display none -initrd /android1/boot-utils/images/s390/rootfs.cpio > > -kernel /android0/kernel-all/arch/s390/boot/bzImage -m 512m > > -nodefaults -serial mon:stdio > > > > Is there a preferred kernel config or additional flags to QEMU I > > should be using to avoid this error? It's also possible that there's > > a bug in the kernel image, but given that it fails very early with no > > other output, I am slightly suspicious of that. > > > > Maybe that helps ? From my builders: > > # qemu only supports MARCH_Z900. Older kernels select it as default, > # but newer kernels may select MARCH_Z196. > sed -i -e '/CONFIG_MARCH_Z/d' ${defconfig} > sed -i -e '/HAVE_MARCH_Z/d' ${defconfig} > echo "CONFIG_MARCH_Z900=y" >> ${defconfig} > echo "CONFIG_PCI=y" >> ${defconfig} $ clang -march=z900 --target=s390x-linux-gnu -c -x c /dev/null -o - error: unknown target CPU 'z900' note: valid target CPU values are: arch8, z10, arch9, z196, arch10, zEC12, arch11, z13, arch12, z14, arch13, z15 Hopefully qemu supports something newer than Z900? Or can we change arch/s390/Kconfig:255 to use a different arch? Is arch9 == z900???: 252 config MARCH_Z900 253 bool "IBM zSeries model z800 and z900" 254 select HAVE_MARCH_Z900_FEATURES 255 depends on $(cc-option,-march=z900) 256 help 257 Select this to enable optimizations for model z800/z900 (2064 and 258 2066 series). This will enable some optimizations that are not 259 available on older ESA/390 (31 Bit) only CPUs. -- Thanks, ~Nick Desaulniers
