Hi, Tejun! 02.12.2014, 19:56, "Tejun Heo" <[email protected]>: > Hello, Roman. > > On Fri, Nov 28, 2014 at 07:47:54PM +0300, Roman Gushchin wrote: >> If cgroup_destroy_locked() sets the css refcount to a negative value, >> we get an infinite loop in __css_tryget(). >> >> In this case css_refcnt() returns modified (non-negative value), so >> both (t == v) and (t < 0) conditions are always false. > > I don't follow. The count is biased and modified by unbiasing iff the > value is negative. Here, @v is the unbiased value and @t is the > verbatim value. If @v is different from @t due to unbiasing, @t must > be negative satisfying the second condition and returning NULL, no?
Yep. I missed that we compare t with 0 (not v). Thanks! -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
