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Date: Mon, 5 Oct 2015 18:30:21 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Chen Gang <xili_gchen_5257@hotmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        "kirill.shutemov@linux.intel.com" <kirill.shutemov@linux.intel.com>,
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Subject: Re: [PATCH] mm/mmap.c: Do not initialize retval in mmap_pgoff()
Message-ID: <20151005163021.GB19857@redhat.com>
References: <COL130-W360AE827EAE109246BEB25B9480@phx.gbl>
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On 10/06, Chen Gang wrote:
>
> When fget() fails, can return -EBADF directly.

To me this change actually makes the code more readable and clean.

> Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>

Acked-by: Oleg Nesterov <oleg@redhat.com>

> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -1412,13 +1412,13 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
>  		unsigned long, fd, unsigned long, pgoff)
>  {
>  	struct file *file = NULL;
> -	unsigned long retval = -EBADF;
> +	unsigned long retval;
>  
>  	if (!(flags & MAP_ANONYMOUS)) {
>  		audit_mmap_fd(fd, flags);
>  		file = fget(fd);
>  		if (!file)
> -			goto out;
> +			return -EBADF;
>  		if (is_file_hugepages(file))
>  			len = ALIGN(len, huge_page_size(hstate_file(file)));
>  		retval = -EINVAL;
> @@ -1453,7 +1453,6 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
>  out_fput:
>  	if (file)
>  		fput(file);
> -out:
>  	return retval;
>  }
>  
> -- 
> 1.9.3
> 
>