> > dissolve_free_huge_pages() will either run into the VM_BUG_ON() or a > list corruption and addressing exception when trying to set a memory > block offline that is part (but not the first part) of a hugetlb page > with a size > memory block size. > > When no other smaller hugetlb page sizes are present, the VM_BUG_ON() > will trigger directly. In the other case we will run into an addressing > exception later, because dissolve_free_huge_page() will not work on the > head page of the compound hugetlb page which will result in a NULL > hstate from page_hstate(). > > To fix this, first remove the VM_BUG_ON() because it is wrong, and then > use the compound head page in dissolve_free_huge_page(). > > Also change locking in dissolve_free_huge_page(), so that it only takes > the lock when actually removing a hugepage. > > Signed-off-by: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx> > --- Acked-by: Hillf Danton <hillf.zj@xxxxxxxxxxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>