From: Yaniv Agman <yanivagman@gmail.com>
To: Daniel Borkmann <daniel@iogearbox.net>
Cc: bpf <bpf@vger.kernel.org>,
Andrii Nakryiko <andrii.nakryiko@gmail.com>,
Yonghong Song <yhs@fb.com>
Subject: Re: libbpf error: unknown register name 'r0' in asm
Date: Fri, 9 Oct 2020 21:33:04 +0300 [thread overview]
Message-ID: <CAMy7=ZW6B+aHN-3dAf7-=kK8WpMZ0NmEmeVh67jVPrjsryx9sQ@mail.gmail.com> (raw)
In-Reply-To: <e385d737-1a4b-a1b6-9a2e-23a71d2ca1b7@iogearbox.net>
בתאריך יום ו׳, 9 באוק׳ 2020 ב-21:21 מאת Daniel Borkmann
<daniel@iogearbox.net>:
>
> On 10/9/20 8:09 PM, Yaniv Agman wrote:
> > בתאריך יום ו׳, 9 באוק׳ 2020 ב-20:39 מאת Daniel Borkmann
> > <daniel@iogearbox.net>:
> >>
> >> On 10/9/20 6:56 PM, Yaniv Agman wrote:
> >>> בתאריך יום ו׳, 9 באוק׳ 2020 ב-19:27 מאת Daniel Borkmann
> >>> <daniel@iogearbox.net>:
> >>>>
> >>>> [ Cc +Yonghong ]
> >>>>
> >>>> On 10/9/20 6:05 PM, Yaniv Agman wrote:
> >>>>> Pulling the latest changes of libbpf and compiling my application with it,
> >>>>> I see the following error:
> >>>>>
> >>>>> ../libbpf/src//root/usr/include/bpf/bpf_helpers.h:99:10: error:
> >>>>> unknown register name 'r0' in asm
> >>>>> : "r0", "r1", "r2", "r3", "r4", "r5");
> >>>>>
> >>>>> The commit which introduced this change is:
> >>>>> 80c7838600d39891f274e2f7508b95a75e4227c1
> >>>>>
> >>>>> I'm not sure if I'm doing something wrong (missing include?), or this
> >>>>> is a genuine error
> >>>>
> >>>> Seems like your clang/llvm version might be too old.
> >>>
> >>> I'm using clang 10.0.1
> >>
> >> Ah, okay, I see. Would this diff do the trick for you?
> >
> > Yes! Now it compiles without any problems!
>
> Great, thx, I'll cook proper fix and check with clang6 as Yonghong mentioned.
>
Thanks!
Does this happen because I'm first compiling using "emit-llvm" and
then using llc?
I wish I could use bpf target directly, but I'm then having problems
with includes of asm code (like pt_regs and other stuff)
> >> diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h
> >> index 2bdb7d6dbad2..31e356831fcf 100644
> >> --- a/tools/lib/bpf/bpf_helpers.h
> >> +++ b/tools/lib/bpf/bpf_helpers.h
> >> @@ -72,6 +72,7 @@
> >> /*
> >> * Helper function to perform a tail call with a constant/immediate map slot.
> >> */
> >> +#if __clang_major__ >= 10 && defined(__bpf__)
> >> static __always_inline void
> >> bpf_tail_call_static(void *ctx, const void *map, const __u32 slot)
> >> {
> >> @@ -98,6 +99,9 @@ bpf_tail_call_static(void *ctx, const void *map, const __u32 slot)
> >> :: [ctx]"r"(ctx), [map]"r"(map), [slot]"i"(slot)
> >> : "r0", "r1", "r2", "r3", "r4", "r5");
> >> }
> >> +#else
> >> +# define bpf_tail_call_static bpf_tail_call
> >> +#endif /* __clang_major__ >= 10 && __bpf__ */
> >>
> >> /*
> >> * Helper structure used by eBPF C program
>
next prev parent reply other threads:[~2020-10-09 18:34 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-09 16:05 libbpf error: unknown register name 'r0' in asm Yaniv Agman
2020-10-09 16:27 ` Daniel Borkmann
2020-10-09 16:56 ` Yaniv Agman
2020-10-09 17:39 ` Daniel Borkmann
2020-10-09 18:09 ` Yaniv Agman
2020-10-09 18:21 ` Daniel Borkmann
2020-10-09 18:33 ` Yaniv Agman [this message]
2020-10-09 18:39 ` Andrii Nakryiko
2020-10-09 19:32 ` Yaniv Agman
2020-10-09 19:53 ` Andrii Nakryiko
2020-10-09 20:24 ` Yaniv Agman
2020-10-12 20:03 ` Andrii Nakryiko
2020-10-12 21:48 ` Yaniv Agman
2020-10-12 22:16 ` Andrii Nakryiko
2020-10-09 18:35 ` Andrii Nakryiko
2020-10-09 18:41 ` Daniel Borkmann
2020-10-09 18:59 ` Andrii Nakryiko
2020-10-09 19:08 ` Yonghong Song
2020-10-09 19:33 ` Yaniv Agman
2020-10-09 19:58 ` Daniel Borkmann
2020-10-21 9:43 ` Yaniv Agman
2020-10-21 17:18 ` Daniel Borkmann
2020-10-21 19:33 ` Yaniv Agman
2020-10-09 17:41 ` Yonghong Song
2020-10-09 18:03 ` Andrii Nakryiko
2020-10-09 18:12 ` Yaniv Agman
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