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Date:   Thu, 25 Aug 2022 09:10:07 -0700
From:   Nathan Chancellor <nathan@kernel.org>
To:     Naresh Kamboju <naresh.kamboju@linaro.org>
Cc:     Mike Kravetz <mike.kravetz@oracle.com>,
        linux-mm <linux-mm@kvack.org>,
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Subject: Re: [next] x86: fs/hugetlbfs/inode.c:673:16: error: variable
 'm_index' is uninitialized when used here [-Werror,-Wuninitialized]
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Hi Naresh,

On Thu, Aug 25, 2022 at 04:13:30PM +0530, Naresh Kamboju wrote:
> The x86_64 and i386 clang builds failed due to these warnings / errors
> on Linux next-20220825.
> 
> Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
> 
> fs/hugetlbfs/inode.c:673:16: error: variable 'm_index' is
> uninitialized when used here [-Werror,-Wuninitialized]
>                                                 m_start, m_index, truncate_op);
>                                                          ^~~~~~~
> fs/hugetlbfs/inode.c:651:26: note: initialize the variable 'm_index'
> to silence this warning
>         pgoff_t m_start, m_index;
>                                 ^
>                                  = 0
> 1 error generated.

Thank you for the report! Commit fcc0d3d00d74 ("hugetlb: handle truncate
racing with page faults") introduced this warning; the Intel folks
caught this as well:

https://lore.kernel.org/202208251012.g1mOhhxy-lkp@intel.com/

As an aside, can you please update your contact for our mailing list to
llvm@lists.linux.dev? We do not use the Google Groups list anymore.

Cheers,
Nathan