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Message-ID: <d42dc4ea6f1d473ef4c721cbe67907538bb681a6.camel@sipsolutions.net>
Subject: Re: [PATCH V1] um: Fix compilation warnings
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Richard Weinberger <richard@nod.at>,
        Srinivasarao Pathipati <quic_c_spathi@quicinc.com>
Cc:     anton ivanov <anton.ivanov@cambridgegreys.com>,
        linux-um <linux-um@lists.infradead.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
Date:   Wed, 15 Feb 2023 09:14:39 +0100
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On Tue, 2023-02-14 at 22:57 +0100, Richard Weinberger wrote:
> ----- Urspr=C3=BCngliche Mail -----
> > Von: "Srinivasarao Pathipati" <quic_c_spathi@quicinc.com>
> > static void sig_handler_common(int sig, struct siginfo *si, mcontext_t =
*mc)
> > {
> > -	struct uml_pt_regs r;
> > +	struct uml_pt_regs *r;
> > 	int save_errno =3D errno;
> >=20
> > -	r.is_user =3D 0;
> > +	r =3D malloc(sizeof(struct uml_pt_regs));
>=20
> I fear this is not correct since malloc() is not async-signal safe.

It would probably also be a non-trivial performance regression for
'interrupt' handling.

We _could_ use a static if this really was a problem, but that'd be just
one more thing to undo for SMP, and see my other mail, it's really not
needed to worry about htis.

johannes