Re: [PATCH HID for-next v2 0/9] HID-BPF LLVM fixes, no more hacks

[Jiri Kosina]

On Fri, 13 Jan 2023, Benjamin Tissoires wrote:

> Hi,
> 
> So this is the fix for the bug that actually prevented me to integrate
> HID-BPF in v6.2.
> 
> While testing the code base with LLVM, I realized that clang was smarter
> than I expected it to be, and it sometimes inlined a function or not
> depending on the branch. This lead to segfaults because my current code
> in linux-next is messing up the bpf programs refcounts assuming that I
> had enough observability over the kernel.
> 
> So I came back to the drawing board and realized that what I was missing
> was exactly a bpf_link, to represent the attachment of a bpf program to
> a HID device. This is the bulk of the series, in patch 6/9.
> 
> The other patches are cleanups, tests, and also the addition of the
> vmtests.sh script I run locally, largely inspired by the one in the bpf
> selftests dir. This allows very fast development of HID-BPF, assuming we
> have tests that cover the bugs :)
> 
> 
> changes in v2:
> - took Alexei's remarks into account and renamed the indexes into
>   prog_table_index and hid_table_index
> - fixed unused function as reported by the Intel kbuild bot

I've now applied this on top of the previous work in 
hid.git#for-6.3/hid-bpf

-- 
Jiri Kosina
SUSE Labs