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Subject: Re: [PATCH v2] x86/cpu: replacing the open-coded shift with BIT(x)
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
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References: <20221101111418.816139-1-cuigaosheng1@huawei.com>
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From:   cuigaosheng <cuigaosheng1@huawei.com>
Message-ID: <e38b1702-c29a-96fc-8fa2-139006fd4d27@huawei.com>
Date:   Tue, 1 Nov 2022 22:05:21 +0800
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Yes, maybe we can do the same thing with BIT(), so I add other modifications, should I remove them?

Thanks very much!

On 2022/11/1 21:43, Jason A. Donenfeld wrote:
> On Tue, Nov 1, 2022 at 2:37 PM cuigaosheng <cuigaosheng1@huawei.com> wrote:
>>> 215 [ 0.953146][ T0] UBSAN: shift-out-of-bounds in mm/shmem.c:3749:18
>>> 216 [ 0.953863][ T0] left shift of 1 by 31 places cannot be represented in type 'int'
> Isn't this just an issue with `1 << 31` needing to be `1U << 31`?
>
> Jason
> .