On May 23, 2023 8:52:53 PM PDT, "Daniel Díaz" <daniel.diaz@xxxxxxxxxx> wrote: >Hello! > >On Tue, 23 May 2023 at 00:28, Vlastimil Babka <vbabka@xxxxxxx> wrote: >> On 5/22/23 20:23, Daniel Díaz wrote: >> > Hello! >> > >> > Would the stable maintainers please consider backporting the following >> > commit to the 6.1? We are trying to build gki_defconfig (plus a few >> > extras) on Arm64 and test it under Qemu-arm64, but it fails to boot. >> > Bisection has pointed here. >> >> You mean the bisection was done to find the first "good" commit between 6.1 >> and e.g. 6.3? >> >> As others said, this commit wasn't expected to be a fix to a known bug. >> Maybe you found one that we didn't know of, or it might be accidentaly >> masking some other bug. > >How interesting! Yes, we happened to run a bisection between v6.1 and >v6.3 and we found where it started working with the following >configuration: > https://storage.tuxsuite.com/public/linaro/daniel/builds/2QA2CHQUpqKe27FyMZrBNILVwXi/config Ah yes, from CONFIG_UBSAN_BOUNDS=y and CONFIG_UBSAN_TRAP=y This was a known issue in upstream, oddly only exposed on arm64. Something re-broke with __alloc_size after commit 93dd04ab0b2b had tried to work around it. I didn't think any kernel released with this broken, though, so perhaps what broke it got added to -stable? >With that patch on top of v6.1.29 it boots fine under Qemu-arm64; as >v6.1.y stands, it panics with this: It should be fine to backport the patch, IMO. -- Kees Cook
