From: Isaac J. Manjarres Date: Thu, 20 Nov 2025 19:42:22 +0000 (+0200) Subject: mm/mm_init: fix hash table order logging in alloc_large_system_hash() X-Git-Tag: v6.1.159~96 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fa5e0b835dad7280a04814c420e4d83b169ad41a;p=thirdparty%2Fkernel%2Fstable.git mm/mm_init: fix hash table order logging in alloc_large_system_hash() [ Upstream commit 0d6c356dd6547adac2b06b461528e3573f52d953 ] When emitting the order of the allocation for a hash table, alloc_large_system_hash() unconditionally subtracts PAGE_SHIFT from log base 2 of the allocation size. This is not correct if the allocation size is smaller than a page, and yields a negative value for the order as seen below: TCP established hash table entries: 32 (order: -4, 256 bytes, linear) TCP bind hash table entries: 32 (order: -2, 1024 bytes, linear) Use get_order() to compute the order when emitting the hash table information to correctly handle cases where the allocation size is smaller than a page: TCP established hash table entries: 32 (order: 0, 256 bytes, linear) TCP bind hash table entries: 32 (order: 0, 1024 bytes, linear) Link: https://lkml.kernel.org/r/20251028191020.413002-1-isaacmanjarres@google.com Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Isaac J. Manjarres Reviewed-by: Mike Rapoport (Microsoft) Reviewed-by: David Hildenbrand Cc: Signed-off-by: Andrew Morton (cherry picked from commit 0d6c356dd6547adac2b06b461528e3573f52d953) Signed-off-by: Mike Rapoport (Microsoft) Signed-off-by: Sasha Levin --- diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 86066a2cf258a..d760b96604eca 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -9225,7 +9225,7 @@ void *__init alloc_large_system_hash(const char *tablename, panic("Failed to allocate %s hash table\n", tablename); pr_info("%s hash table entries: %ld (order: %d, %lu bytes, %s)\n", - tablename, 1UL << log2qty, ilog2(size) - PAGE_SHIFT, size, + tablename, 1UL << log2qty, get_order(size), size, virt ? (huge ? "vmalloc hugepage" : "vmalloc") : "linear"); if (_hash_shift)