In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
sched\/core: Handle pick_task() releasing the rq lock<\/p>\n
Core scheduling’s pick_next_task() breaks when a ->pick_task()
\nimplementation can release the rq lock. The selection state derived on entry
\nis only valid while the lock is held continuously. Once a pick can drop the
\nlock, an interleaving selection can invalidate all of it: the single-CPU
\nfast path can commit an uncookied pick although the core went cookied during
\nthe release, and forceidle committed by the interleaving selection skews the
\nrestarted pass’s accounting.<\/p>\n
Fix it by restarting the whole selection when a pick returns RETRY_TASK
\nafter releasing the lock: a single restart point above the state derivation
\nreplaces the per-loop restart labels, so a retry picks up state committed by
\ninterleaving selections and accounts and resets forceidle like a fresh
\nselection would.<\/p>\n
need_sync and fi_before latch across retries. Clock validity can’t be
\nre-derived – there is no program-ordered way to tell whether the own and
\ncore rq clocks are still updated after the lock was released, as other
\nlockers’ pin cycles may or may not have invalidated them. When restarting,
\nclear core_clock_updated so that the sibling loop re-updates the core rq,
\nand update the own rq clock if invalidated.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
sched\/core: Handle pick_task() releasing the rq lock<\/p>\n
Core scheduling’s pick_next_task() breaks when a ->pick_task()
\nimplementation<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-21443","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/21443","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=21443"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=21443"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=21443"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}