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Date: Mon, 9 Sep 2024 10:27:42 -0700
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Subject: Re: Kernel oops caused by signed divide
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To: Zac Ecob <zacecob@protonmail.com>,
 "bpf@vger.kernel.org" <bpf@vger.kernel.org>
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From: Yonghong Song <yonghong.song@linux.dev>
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On 9/9/24 10:21 AM, Zac Ecob wrote:
> Hello,
>
> I recently received a kernel 'oops' about a divide error.
> After some research, it seems that the 'div64_s64' function used for the 'MOD'/'REM' instructions boils down to an 'idiv'.
>
> The 'dividend' is set to INT64_MIN, and the 'divisor' to -1, then because of two's complement, there is no corresponding positive value, causing the error (at least to my understanding).

Could you provide a reproducible test case for this? It will make it easy to debug the issue.