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charset=utf-8 Content-Disposition: inline X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 8BF0040008 X-Rspam-User: X-Stat-Signature: o1ky75yscjnqzb915sz9tgxsoa6a35z5 X-HE-Tag: 1741176762-200044 X-HE-Meta: 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 zYrGw564 TFEQ+CwCJfv2KS6bFicwr++uR9RMx2VuCeLKEBiYnk39xEhjS+xxHahFErTkQ5dXfmJIWhRNNfvvDdL5Zwhp50dfv3PMZOqVtRQFfy6Q5gJOVHAB1LzuvQhAnQdF4pEfWvZE+pMs+cqLGCdbPX/96mfpHeN6JvXpd9VHpxZ4KnD1mkwwmC6aWIPt+4CIod1wNm9Ms84qAxSyoN9smShMoYGyfzeXLiAC61cv3LC8tzUHOeDq29Btnb+HJwoFOc2If4Wzl45Flc6l8NdMwEzkmYx4+Ldtl7Uu/y42mk9dUCY8SsuFwEtU9Yt0g3qbP5QgDtNCnFZJLyoWxTCFvhaYVrwoJcJ1sxC9S6A8alo1GWKBgj9rGX0WO+P+t0G5V//RhCHi6y5r9bP4COqi2HZW+aczGf1Iogr29tsHdBQn9OOtO3kk= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Mar 05, 2025 at 11:54:09AM +0800, Liu Shixin wrote: > In alloc_surplus_hugetlb_folio(), we increase nr_huge_pages and > surplus_huge_pages separately. In the middle window, if we set > nr_hugepages to smaller and satisfy count < persistent_huge_pages(h), > the surplus_huge_pages will be increased by adjust_pool_surplus(). > > After adding delay in the middle window, we can reproduce the problem > easily by following step: > > 1. echo 3 > /proc/sys/vm/nr_overcommit_hugepages > 2. mmap two hugepages. When nr_huge_pages=2 and surplus_huge_pages=1, > goto step 3. > 3. echo 0 > /proc/sys/vm/nr_huge_pages > > Finally, nr_huge_pages is less than surplus_huge_pages. > > To fix the problem, call only_alloc_fresh_hugetlb_folio() instead and > move down __prep_account_new_huge_page() into the hugetlb_lock. > > Fixes: 0c397daea1d4 ("mm, hugetlb: further simplify hugetlb allocation API") > Signed-off-by: Liu Shixin Acked-by: Peter Xu -- Peter Xu