From 0d6c356dd6547adac2b06b461528e3573f52d953 Mon Sep 17 00:00:00 2001 From: "Isaac J. Manjarres" Date: Tue, 28 Oct 2025 12:10:12 -0700 Subject: [PATCH] mm/mm_init: fix hash table order logging in alloc_large_system_hash() 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 --- mm/mm_init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/mm_init.c b/mm/mm_init.c index 3db2dea7db4c..7712d887b696 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -2469,7 +2469,7 @@ 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) -- 2.47.3