From mboxrd@z Thu Jan  1 00:00:00 1970
From: Theodore Ts'o <tytso@mit.edu>
Subject: Re: [sparc64] sigbus in e2fsck
Date: Wed, 31 Aug 2016 21:26:20 -0400
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Cc: Anatoly Pugachev <matorola@gmail.com>, linux-ext4@vger.kernel.org,
        debian-sparc <debian-sparc@lists.debian.org>
To: "Darrick J. Wong" <darrick.wong@oracle.com>
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On Tue, Aug 30, 2016 at 01:25:10PM -0700, Darrick J. Wong wrote:
> 
> AFAICT, each bh is malloc'd via e2fsck_allocate_memory and nothing seems
> to guarantee that the char b_data[1024] will be aligned to a multiple of
> 8 (it certainly isn't on x64), so I guess this isn't much of a surprise.
> 
> We could change b_data to a pointer and then posix_memalign it.

Actually, all we need to do is to rearrange the structure elements so
it looks like this:

	unsigned long long b_blocknr;
	char            b_data[1024];
};

Since b_blocknr will need to be eight byte aligned, this will also
ensure that b_data will also be aligned correctly.

       	    	   	     		- Ted