linux-kernel - linux-6.19-rc4/kernel/kexec_core.c:425: Possible loss of data ?

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Message-ID:
 <VI1PR02MB395224C3D5F37DEDA794AED09C84A@VI1PR02MB3952.eurprd02.prod.outlook.com>
Date: Wed, 7 Jan 2026 14:32:05 +0000
From: David Binderman <dcb314@...mail.com>
To: "akpm@...ux-foundation.org" <akpm@...ux-foundation.org>, "bhe@...hat.com"
	<bhe@...hat.com>, "kexec@...ts.infradead.org" <kexec@...ts.infradead.org>,
	LKML <linux-kernel@...r.kernel.org>
Subject: linux-6.19-rc4/kernel/kexec_core.c:425: Possible loss of data ?

Hello there,

Static analyser cppcheck says:

linux-6.19-rc4/kernel/kexec_core.c:425:7: style: int result is assigned to long variable. If the variable is long to avoid loss of information, then you have loss of information. [truncLongCastAssignment]

Source code is

    size = (1 << order) << PAGE_SHIFT;

I have no idea how large order gets, but if it gets over about
30 or so, then IMHO there will be a loss of bits.

Perhaps some sanity check on the value of order would
be a good idea ? Either that or

    size = (1UL << order) << PAGE_SHIFT;

might be better code.

Regards

David Binderman