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a=ed25519-sha256; t=1783548773; l=2183; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=8pgD6+H5WXDhqxeVR1T9DEMEA9n+rne9MvjgkpNJ/6Y=; b=tmNC77AlJSVebS5RY5iI4MPVusjxMx2IC/1THhUAM6VizHc2+2UAt3vcvxbqcvzVnISeBK1ur Nnldn6syc2gBrP7TLZEdPYvfD1LeleDU15RVNgSoiQOUF80MZtxysjz X-Developer-Key: i=ackerleytng@google.com; a=ed25519; pk=sAZDYXdm6Iz8FHitpHeFlCMXwabodTm7p8/3/8xUxuU= X-Endpoint-Received: by B4 Relay for ackerleytng@google.com/20260225 with auth_id=649 X-Original-From: Ackerley Tng Reply-To: ackerleytng@google.com X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 1BF0D40002 X-Stat-Signature: n8sx6mif1iriwsnqkx8n5koi1d5ot6w4 X-HE-Tag: 1783548774-654439 X-HE-Meta: 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 R+B2r6IR Q3qPajtO0iT8LbgKoXfLjYtzsFdQZUlHDxTFXAHd5IrpDjC/uRrboKnO/w8peQjgK+rzOk6Bz6ZMelQuvJ00hCgO2LYUxY+q5MZ9YLx/+4Nbw3PyrZBviBk/pxHY5y9q3Rv7F72DbwKCwFJP3tiR523HLQ1kDCq9B1hFlYQtbv6YXYeypC8ujFQmtduULqNpjB7YQwbQOKcUfHjBHCn4YS46o9FmLEf59pF3OjUMzbZOsNvHkkqCxAy6syEBV9u9BGPilat52fZNF3kL5UAbyw/RQk5/UjCwPWcCVwQHs27OWZxIv1uL3WhwY+kYG6A/zYGLSCKQcdf4qOOS5OGDHkBb2ZotQ17/dKOuvmE8rvZaQZNNUG1tYvsZ2bvk+5+krnp4B44uqXjiw5ZxT+NZBPM4oobfgfIsDsr6Ah9vqzj96S9OiT6v+HHufHi+hH038eWbrJCps/KS3xYIzlU8XdrdZxUOePzO05Ugr Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Ackerley Tng When alloc_hugetlb_folio() fails early (e.g. buddy allocation failure or hugetlb cgroup charging failure) and gbl_chg == 1 (meaning a reservation was not used, but a global page was allocated instead), the subpool page acquired via hugepage_subpool_get_pages() must still be returned. Currently, the error path out_subpool_put: only calls hugepage_subpool_put_pages() if !gbl_chg is true. If gbl_chg is 1, it skips it, permanently leaking the subpool's used_hpages counter. With the earlier patch to always track used_hpages in the subpool, always call hugepage_subpool_put_pages() if map_chg is true to consistently restore the page to the subpool. Only call hugetlb_acct_memory() to adjust global reservations if gbl_chg == 0 since gbl_chg == 0 indicates a subpool (and global) reservation was used. Fixes: a833a693a490e ("mm: hugetlb: fix incorrect fallback for subpool") Cc: stable@vger.kernel.org Signed-off-by: Ackerley Tng --- mm/hugetlb.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index ee5e99c1894b9..4093c1c0a4a1d 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2852,7 +2852,7 @@ struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, struct hugepage_subpool *spool = subpool_vma(vma); struct hstate *h = hstate_vma(vma); struct folio *folio; - long retval, gbl_chg, gbl_reserve; + long retval, gbl_chg; map_chg_state map_chg; int ret, idx; struct hugetlb_cgroup *h_cg = NULL; @@ -3003,13 +3003,11 @@ struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, hugetlb_cgroup_uncharge_cgroup_rsvd(idx, pages_per_huge_page(h), h_cg_rsvd); out_subpool_put: - /* - * put page to subpool iff the quota of subpool's rsv_hpages is used - * during hugepage_subpool_get_pages. - */ - if (map_chg && !gbl_chg) { - gbl_reserve = hugepage_subpool_put_pages(spool, 1); - hugetlb_acct_memory(h, -gbl_reserve); + if (map_chg) { + long gbl_reserve = hugepage_subpool_put_pages(spool, 1); + + if (!gbl_chg) + hugetlb_acct_memory(h, -gbl_reserve); } -- 2.55.0.795.g602f6c329a-goog