From: Andrew Morton <akpm@linux-foundation.org>
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Luigi Rizzo <lrizzo@google.com>, Yonghong Song <yhs@fb.com>,
Liam Howlett <liam.howlett@oracle.com>,
Peter Zijlstra <peterz@infradead.org>,
Jason Gunthorpe <jgg@ziepe.ca>,
Daniel Borkmann <daniel@iogearbox.net>,
Michel Lespinasse <walken@google.com>, bpf <bpf@vger.kernel.org>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
Alexei Starovoitov <ast@kernel.org>,
Andrii Nakryiko <andrii@kernel.org>,
"kernel-team@fb.com" <kernel-team@fb.com>
Subject: Re: [PATCH mm/bpf v2] mm: bpf: add find_vma_no_check() without lockdep_assert on mm->mmap_lock
Date: Wed, 8 Sep 2021 11:15:27 -0700 [thread overview]
Message-ID: <20210908111527.9a611426e257d55ccbbf46eb@linux-foundation.org> (raw)
In-Reply-To: <20210908180258.yjh62e5oouckar5b@ast-mbp.dhcp.thefacebook.com>
On Wed, 8 Sep 2021 11:02:58 -0700 Alexei Starovoitov <alexei.starovoitov@gmail.com> wrote:
> > Please describe the expected userspace-visible change from Peter's
> > patch in full detail?
>
> User space expects build_id to be available. Peter patch simply removes
> that feature.
Are you sure? He ends up with
static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs,
u64 *ips, u32 trace_nr, bool user)
{
int i;
/* cannot access current->mm, fall back to ips */
for (i = 0; i < trace_nr; i++) {
id_offs[i].status = BPF_STACK_BUILD_ID_IP;
id_offs[i].ip = ips[i];
memset(id_offs[i].build_id, 0, BUILD_ID_SIZE_MAX);
}
return;
}
and you're saying that userspace won't like this because we didn't set
BPF_STACK_BUILD_ID_VALID?
next prev parent reply other threads:[~2021-09-08 18:15 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-08 4:44 Yonghong Song
2021-09-08 12:20 ` Daniel Borkmann
2021-09-08 13:53 ` Jason Gunthorpe
2021-09-08 14:15 ` Peter Zijlstra
2021-09-08 14:43 ` Luigi Rizzo
2021-09-08 15:12 ` Liam Howlett
2021-09-08 16:09 ` Yonghong Song
2021-09-08 17:09 ` Luigi Rizzo
2021-09-08 17:21 ` Alexei Starovoitov
2021-09-08 17:52 ` Andrew Morton
2021-09-08 18:02 ` Alexei Starovoitov
2021-09-08 18:15 ` Andrew Morton [this message]
2021-09-08 18:20 ` Alexei Starovoitov
2021-09-08 18:30 ` Liam Howlett
2021-09-08 18:45 ` Yonghong Song
2021-09-08 18:49 ` Jason Gunthorpe
2021-09-08 19:11 ` Yonghong Song
2021-09-08 23:33 ` Jason Gunthorpe
2021-09-09 5:50 ` Yonghong Song
2021-09-09 8:05 ` Peter Zijlstra
2021-09-08 18:43 ` Liam Howlett
2021-09-08 19:42 ` Alexei Starovoitov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210908111527.9a611426e257d55ccbbf46eb@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=alexei.starovoitov@gmail.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=jgg@ziepe.ca \
--cc=kernel-team@fb.com \
--cc=liam.howlett@oracle.com \
--cc=linux-mm@kvack.org \
--cc=lrizzo@google.com \
--cc=peterz@infradead.org \
--cc=walken@google.com \
--cc=yhs@fb.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox