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charset=us-ascii Content-Disposition: inline On Thu, May 25, 2023 at 11:25:05AM -0400, Waiman Long wrote: > Since the percpu blkg_iostat_set's that are linked in the lockless list will > be freed if the corresponding blkcg_gq is freed, we need to flush the > lockless list to avoid potential use-after-free in a future > cgroup_rstat_flush*() call. Ah, so that was meant to the situation post-patch (that removes refcnt of entries on list lockless). (It sounded like an answer to Yosry's question about cgroup_rstat_flush in offline_css in pre-patch version. Nevermind, this would need other adjustments.) Thanks, Michal --2lov5w6hllmz7efr Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTrXXag4J0QvXXBmkMkDQmsBEOquQUCZHEgigAKCRAkDQmsBEOq uWtDAP9qS2v1mJD+JAJWF4NNLRntYEptKWXuYC5WuXbwLeHXVgEAv+bVtSIdoISo P9lLBk2p49pDqTse3bR1E50c/pTTQgU= =Aa81 -----END PGP SIGNATURE----- --2lov5w6hllmz7efr--