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Date:   Fri, 03 Apr 2020 21:26:27 +1000
From:   Nicholas Piggin <npiggin@gmail.com>
Subject: Re: [PATCH v11 3/8] powerpc/perf: consolidate read_user_stack_32
To:     Michal =?iso-8859-1?q?Such=E1nek?= <msuchanek@suse.de>
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Michal Such=C3=A1nek's on April 3, 2020 8:52 pm:
> Hello,
>=20
> there are 3 variants of the function
>=20
> read_user_stack_64
>=20
> 32bit read_user_stack_32
> 64bit read_user_Stack_32

Right.

> On Fri, Apr 03, 2020 at 05:13:25PM +1000, Nicholas Piggin wrote:
[...]
>>  #endif /* CONFIG_PPC64 */
>> =20
>> +static int read_user_stack_32(unsigned int __user *ptr, unsigned int *r=
et)
>> +{
>> +	return __read_user_stack(ptr, ret, sizeof(*ret));
> Does not work for 64bit read_user_stack_32 ^ this should be 4.
>=20
> Other than that it should preserve the existing logic just fine.

sizeof(int) =3D=3D 4 on 64bit so it should work.

Thanks,
Nick
=