On Mon, 13 May 2002, Kenneth D. Merry wrote:
> [ Al Viro CCed, since from the changelog for 2.4.11, it looks like he may
> have submitted the patch in question. ]
>
> I was looking through the atari partitioning code (fs/partitions/atari.c)
> in 2.4.18 (from what I can see in 2.4.19-pre8, it hasn't changed) and I
> noticed something (starting at about line 144) that may be a problem:
>
> for (; pi < &rs->icdpart[8] && minor < m_lim; minor++, p
> i++) {
> /* accept only GEM,BGM,RAW,LNX,SWP partitions */
> if (!((pi->flg & 1) && OK_id(pi->id)))
> continue;
> part_fmt = 2;
> add_gd_partition (hd, minor,
> be32_to_cpu(pi->st),
> be32_to_cpu(pi->siz));
> }
> printk(" >");
>
> This code changed in 2.4.11, and was previously:
>
> for (; pi < &rs->icdpart[8] && minor < m_lim; minor++, pi++)
> {
> /* accept only GEM,BGM,RAW,LNX,SWP partitions */
> if (pi->flg & 1 &&
> (memcmp (pi->id, "GEM", 3) == 0 ||
> memcmp (pi->id, "BGM", 3) == 0 ||
> memcmp (pi->id, "LNX", 3) == 0 ||
> memcmp (pi->id, "SWP", 3) == 0 ||
> memcmp (pi->id, "RAW", 3) == 0) )
> {
> part_fmt = 2;
> add_gd_partition (hd, minor, be32_to_cpu(pi->st),
> be32_to_cpu(pi->siz));
> }
> }
> printk(" >");
>
> Note that the test was reversed, but not fully. You want only active
> partitions of the specified types to be added, but with the code as it is
> now, only partitions that are active and *not* of the correct type will get
> added.
No, the change is correct.
Note that the ! in the first snippet is in front of the whole expression,
and it's pretty obvious that the reversed test for (a && b) is !(a && b).
The latter is equivalent to (!a || !b), which seems to be what you're
thinking, but you didn't get it right and put !(a || !b) which is wrong.
--Kai
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This archive was generated by hypermail 2b29 : Tue May 14 2002 - 12:00:22 EST