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Message-ID: <0ab4f3ea2bd97c7067ed332c0128829f4a7ea596.camel@redhat.com>
Subject: Re: [PATCH] net: skbuff: fix missing a __noreturn annotation warning
From:   Paolo Abeni <pabeni@redhat.com>
To:     Kuniyuki Iwashima <kuniyu@amazon.com>, linmiaohe@huawei.com
Cc:     davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org
Date:   Tue, 30 May 2023 12:28:25 +0200
In-Reply-To: <20230527040038.6783-1-kuniyu@amazon.com>
References: <20230527110409.497408-1-linmiaohe@huawei.com>
         <20230527040038.6783-1-kuniyu@amazon.com>
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On Fri, 2023-05-26 at 21:00 -0700, Kuniyuki Iwashima wrote:
> From: Miaohe Lin <linmiaohe@huawei.com>
> Date: Sat, 27 May 2023 19:04:09 +0800
> > Add __noreturn annotation to fix the warning:
> >  net/core/skbuff.o: warning: objtool: skb_push+0x3c: skb_panic() is mis=
sing a __noreturn annotation
> >  net/core/skbuff.o: warning: objtool: skb_put+0x4e: skb_panic() is miss=
ing a __noreturn annotation
>=20
> What arch are you using ?
>=20
> IIUC, BUG() should have an annotation for objtool, for
> example, __builtin_unreachable() for x86.
>=20
> Maybe the arch is missing such an annotation ?
>=20
> Also I'm curious why objtool complains about only skb_push(),
> there should be more non-inline functions that has BUG().

AFAICS, the BUG() macro implementation should already carry the
__noreturn annotation, via panic() or other arch-specific way.

This looks like the old toolchain not being able to
successfully/correctly propagate the annotation???

I think we can drop this patch.

Cheers,

Paolo