Re: [PATCH] /dev/mem: Fix wrong error on accessing beyond valid memoryaddresses.

From: H. Peter Anvin
Date: Mon Nov 14 2011 - 17:12:42 EST


On 11/14/2011 02:11 PM, Andrei Warkentin wrote:

EOF seems wrong to me (not as bad as EFAULT, but still wrong).

Although that was what we had discussed, I do not return -EOF in the patch. As you
mention - that would be wrong. I played around with other devices (block, actually),
and if you attempt to read(2) beyond the end, read(2) simply returns 0, as in
zero bytes read out. Of course, lseek(2) beyond the end should return -EINVAL, as
well, so that is what that patch I CCd you on accomplishes.


0 is EOF.

This is not a block device -- comparing to block devices is pointless. There is no "end" to /dev/mem, so this is a totally meaningless comparison.

-hpa


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/