On Thu, Sep 17, 2026 at 10:19:33PM +0200, Peter Schneider wrote:
When I revert 22ae428b0045981bd19f8c75f700a67198062f32 from rc1, the boot crash goes away and my machine boots successfully.
Thanks for confirming, and for the crash photo from the Ivy Bridge box in your earlier mail - that is the same bug. Dropped from the 6.12 queue:
b1b7c045e808 ("mm/hugetlb: initialize gigantic bootmem hugepage struct pages earlier")
The backport relocates gather_bootmem_prealloc() into page_alloc_init_late(), which on 6.12 runs before anything has initialized the per-node huge_boot_pages[] list heads - upstream that is done unconditionally in hugetlb_bootmem_alloc() since v6.15, which 6.12 does not have. Any CONFIG_HUGETLB_PAGE=y kernel booted without hugepagesz=/hugepages= walks an all-zero list head and faults.
However, then I have another weirdo in the dmesg output: [ 65.573307] WARNING: CPU: 14 PID: 0 at kernel/sched/fair.c:5303 place_entity+0x13b/0x140
That one is a separate 6.12 problem and your follow-up bisect nailed it - I've replied there with what was dropped for it.