On 10/12/2018 10:53, Ravi Bangoria wrote: > Hi, > > Can you please provide more details. I don't understand how this patch > can cause boot failure.
The kernel Oops caused by the nouveau driver was treated as a boot failure in the BayLibre lab, although it did not necessarily mean the kernel had failed to boot to a login prompt. This configuration has now been changed to stop reporting things like NULL pointer dereferences as boot failures, the only criteria for a KernelCI boot test being to be able to get to the login prompt. Side note: We may start reporting non-fatal errors found in the kernel log somehow as part of an extended boot test with some extra checks in the future, but that's a different topic. > From the log found at > https://storage.kernelci.org/mainline/master/v4.20-rc5-79-gabb8d6ecbd8f/arm/multi_v7_defconfig+CONFIG_EFI=y+CONFIG_ARM_LPAE=y/lab-baylibre/boot-tegra124-jetson-tk1.html > [...] > > > Both PC and LR are pointing to drm_* code. I don't see this anyway related to > uprobes. Did I miss anything? So for this particular bisection, there is a known problem in the nouveau driver, pending this fix to be applied: https://patchwork.freedesktop.org/patch/263587/ I haven't investigated how your patch in uprobes.c makes the issue appear in the nouveau driver but I suspect it's merely uncovering it. The patch linked above does fix the actual problem in the nouveau driver. >> * This automated bisection report was sent to you on the basis * >> * that you may be involved with the breaking commit it has * >> * found. No manual investigation has been done to verify it, * >> * and the root cause of the problem may be somewhere else. * Seems like this is just what happened in this case. Guillaume