x86/setup: call hugetlb_bootmem_alloc early

Call hugetlb_bootmem_allloc in an earlier spot in setup, after
hugelb_cma_reserve.  This will make vmemmap preinit of the sections
covered by the allocated hugetlb pages possible.

Link: https://lkml.kernel.org/r/20250228182928.2645936-21-fvdl@google.com
Signed-off-by: Frank van der Linden <fvdl@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Roman Gushchin (Cruise) <roman.gushchin@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch/x86/kernel/setup.c

@@ -1108,8 +1108,10 @@ void __init setup_arch(char **cmdline_p)
 	initmem_init();
 	dma_contiguous_reserve(max_pfn_mapped << PAGE_SHIFT);
 
-	if (boot_cpu_has(X86_FEATURE_GBPAGES))
+	if (boot_cpu_has(X86_FEATURE_GBPAGES)) {
 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
+		hugetlb_bootmem_alloc();
+	}
 
 	/*
 	 * Reserve memory for crash kernel after SRAT is parsed so that it