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Subject: RE:(2) [PATCH 3/4] scripts/checkstack.pl: add arm push handling for
 stack usage
Reply-To: v.narang@samsung.com
From:   Vaneet Narang <v.narang@samsung.com>
To:     Masahiro Yamada <masahiroy@kernel.org>,
        Maninder Singh <maninder1.s@samsung.com>
CC:     "George G. Davis" <george_davis@mentor.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        AMIT SAHRAWAT <a.sahrawat@samsung.com>,
        Arnd Bergmann <arnd@arndb.de>, Andi Kleen <ak@linux.intel.com>
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Message-ID: <20200507133220epcms5p87e370759fbc8aecca3093c503dd99b4c@epcms5p8>
Date:   Thu, 07 May 2020 19:02:20 +0530
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Sender: linux-kernel-owner@vger.kernel.org
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fixes=20bug=20in=20stack=20usage=20calculation.=0D=0A=0D=0AWe=20were=20comp=
aring=20stack=20usage=20of=20ARM=20with=20ARM64=20and=20found=20big=20gap.=
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ly.=0D=0AIt=20only=20considers=20stack=20used=20by=20local=20variables=20bu=
t=20it=20doesn't=20consider=20=0D=0Astack=20used=20to=20store=20register=20=
context=20at=20the=20start=20of=20functions.=20=0D=0AThis=20is=20not=20the=
=20case=20with=20ARM64.=20It=20seems=20ARM64=20considers=20both.=0D=0A=0D=
=0AWe=20found=20even=20stack=20variables=20are=20of=20same=20size=20on=20bo=
th=20target=20but=20=0D=0Aarm64=20stack=20usage=20is=20high.=0D=0A=0D=0ACon=
sidering=20below=20assembly,=20Actual=20stack=20usage=20is=20492=20but=20cu=
rrent=20script=20reports=20448.=0D=0Apush=20instruction=20uses=2044=20bytes=
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=20=20=20=20=20sp,=20sp,=20=23448=20=20=20=20;=200x1C0=0D=0A=0D=0AThanks=20=
&=20Regards,=0D=0AVaneet=20Narang=0D=0A=C2=A0=0D=0A=C2=A0=C2=A0