Re: [PATCH v2 bpf-next] selftests/bpf: Use %p for pointer formatting

[Sebastian Andrzej Siewior <bigeasy@linutronix.de>]

On 2026-09-18 11:38:34 [+0000], bot+bpf-ci@kernel.org wrote:
> > selftests/bpf: Use %p for pointer formatting
> >
> > Networking used to print the socket pointer with %p as output in the
> > /proc interface. This was later changed to %pK in order not to reveal
> > the actual pointer value. The output format has then been copied to bpf
> > tests which produce the same format including the %pK format modifier.
> >
> > Networking recently replaced the socket output with a plain 0 because
> > the socket pointer added no value to the output and the %pK should be
> > removed from library handling. The format remained otherwise unchanged in
> > order not to break any tools which parsing this information.
> >
> > This change removes the %pK modifier from bpf, following the change in
> > networking.
> 
> Does this subject line accurately describe what the patch does?

Oh. The %pK gets removed, not replaced with %p.

> Looking at the actual changes, no %p format specifier is introduced
> anywhere in the test code:
> 
> - bpf_iter_netlink.c gets a literal "0  " string
> - bpf_iter_tcp4.c / bpf_iter_tcp6.c / bpf_iter_udp4.c / bpf_iter_udp6.c
>   get a literal "0" string
> - bpf_iter_unix.c gets "%08u" with a constant 0 argument
> - test_snprintf.c simply drops the %pK specifier (its remaining %p was
>   already present before this patch)
> 
> The only place where %p appears in the patch is in README.rst, in a
> historical verifier log excerpt.
> 
> The body text says "This change removes the %pK modifier from bpf",
> which matches the v1 subject "selftests/bpf: Replace %pK output with 0"
> rather than this v2 subject.

Indeed.

> A few additional points:
> 
> The changelog is unchanged from v1 and doesn't mention the
> header/column-width edits this version adds:
> - bpf_iter_netlink.c "sk" column changed from 17 to 3 chars
> - bpf_iter_unix.c "Num" column changed from 18 to 10 chars
> 
> This seems relevant since the body asserts "The format remained
> otherwise unchanged in order not to break any tools".

This updates the output so the column width aligns with the output.
"Format unchanged" means no items were removed or reordered.

> The referenced networking commit isn't named in the message. Looking at
> the v1 discussion, commit 7c0ec6288b497 ("net: Replace %pK output with
> 0") was cited below the --- separator, so it's absent from the committed
> message. That commit doesn't appear to be in this tree yet (checking
> net/netlink/af_netlink.c, net/unix/af_unix.c, net/ipv4/udp.c and the
> tcp_ipv[46].c files still use %pK), which would make a Link: or commit
> reference useful for readers.
> 
> > order not to break any tools which parsing this information.
> 
> This isn't a bug, but there's a grammar error here ("which parsing"
> should be "which are parsing").

Okay.

Sebastian