On Thu, Feb 27, 2014 at 11:03 PM, Kirill A. Shutemov <[email protected]> wrote: > Sasha Levin wrote: >> Hi all, >> >> While fuzzing with trinity inside a KVM tools guest running latest -next >> kernel I've stumbled on the >> following spew: >> >> [ 1428.146261] kernel BUG at mm/huge_memory.c:2785! > > Hm, interesting. > > It seems we either failed to split huge page on vma split or it > materialized from under us. I don't see how it can happen: > > - it seems we do the right thing with vma_adjust_trans_huge() in > __split_vma(); > - we hold ->mmap_sem all the way from vm_munmap(). At least I don't see > a place where we could drop it; >
Enable CONFIG_DEBUG_VM may show some useful information, at least we can confirm weather rwsem_is_locked(&tlb->mm->mmap_sem) before split_huge_page_pmd(). -- Regards, --Bob -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
