Re: [PATCH v1 4/4] selftests/mm: Add test about uprobe pte be orphan during vma merge

[Pedro Falcato]

On Tue, Jun 10, 2025 at 11:37:29AM +0100, Aishwarya wrote:
> Hi,
> 
> kselftest-mm test 'merge.handle_uprobe_upon_merged_vma' is failing
> against mainline master v6.16-rc1 with Arm64 on Ampere Altra/TX2 in our
> CI. The kernel was built using defconfig along with the additional
> config fragment from:
> 
>   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/tools/testing/selftests/mm/config
> 
> I understand the failure is already being discussed and is expected to be
> addressed by including sys/syscall.h.Sharing this observation here 
> for reference.

This is a different problem.

> 
> A bisect identified commit efe99fabeb11b030c89a7dc5a5e7a7558d0dc7ec as the
> first bad commit. This was bisected against tag v6.16-rc1 from:
> 
>   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
> 
> This test passes on Linux version v6.15-13627-g119b1e61a769.
> 
> Failure log:
> 
>   7151 12:46:54.627936  # # #  RUN           merge.handle_uprobe_upon_merged_vma ...
>   7152 12:46:54.639014  # # f /sys/bus/event_source/devices/uprobe/type
>   7153 12:46:54.639306  # # fopen: No such file or directory
>   7154 12:46:54.650451  # # # merge.c:473:handle_uprobe_upon_merged_vma:Expected read_sysfs("/sys/bus/event_source/devices/uprobe/type", &type) (1) == 0 (0)
>   7155 12:46:54.650730  # # # handle_uprobe_upon_merged_vma: Test terminated by assertion
>   7156 12:46:54.661750  # # #          FAIL  merge.handle_uprobe_upon_merged_vma
>   7157 12:46:54.662030  # # not ok 8 merge.handle_uprobe_upon_merged_vma
> 

So, basically we're not finding the uprobe (I guess CONFIG_UPROBES isn't set in
defconfig, and it's not in the mm/config either), and the test just fails instead
of skipping.

-- 
Pedro