Re: [REGRESSION] v6.0.x fails to boot after updating from v5.19.x

[Greg KH <gregkh@linuxfoundation.org>]

On Thu, Nov 24, 2022 at 01:08:57AM +0000, Dominic Jones wrote:
> > On Fri, Oct 28, 2022 at 02:51:43PM +0000, Dominic Jones wrote:
> > > Updating the machine's kernel from v5.19.x to v6.0.x causes the machine to not
> > > successfully boot. The machine boots successfully (and exhibits stable operation)
> > > with version v5.19.17 and multiple earlier releases in the 5.19 line. Multiple releases
> > > from the 6.0 line (including 6.0.0, 6.0.3, and 6.0.5), with no other changes to the
> > > software environment, do not boot. Instead, the machine hangs after loading services
> > > but before presenting a display manager; the machine instead shows repetitive hard
> > > drive activity at this point and then no apparent activity.
> > > 
> > > ''uname'' output for the machine successfully running v5.19.17 is:
> > > 
> > >     Linux [MACHINE_NAME] 5.19.17 #1 SMP PREEMPT_DYNAMIC Mon Oct 24 13:32:29 2022 i686 Intel(R) Atom(TM) CPU N270 @ 1.60GHz GenuineIntel GNU/Linux
> > > 
> > > The machine is an OCZ Neutrino netbook, running a custom OS build largely similar to
> > > LFS development. The kernel update uses ''make olddefconfig''.
> > 
> > Can you use 'git bisect' to find the offending change that causes this
> > to happen?
> 
> Bisection is complete. Here's what it returned.
> 
> ---
> 
> 3a194f3f8ad01bce00bd7174aaba1563bcc827eb is the first bad commit
> commit 3a194f3f8ad01bce00bd7174aaba1563bcc827eb
> Author: Naoya Horiguchi <naoya.horiguchi@nec.com>
> Date:   Thu Jul 14 13:24:14 2022 +0900
> 
>     mm/hugetlb: make pud_huge() and follow_huge_pud() aware of non-present pud entry
>     
>     follow_pud_mask() does not support non-present pud entry now.  As long as
>     I tested on x86_64 server, follow_pud_mask() still simply returns
>     no_page_table() for non-present_pud_entry() due to pud_bad(), so no severe
>     user-visible effect should happen.  But generally we should call
>     follow_huge_pud() for non-present pud entry for 1GB hugetlb page.
>     
>     Update pud_huge() and follow_huge_pud() to handle non-present pud entries.
>     The changes are similar to previous works for pud entries commit
>     e66f17ff7177 ("mm/hugetlb: take page table lock in follow_huge_pmd()") and
>     commit cbef8478bee5 ("mm/hugetlb: pmd_huge() returns true for non-present
>     hugepage").
>     
>     Link: https://lkml.kernel.org/r/20220714042420.1847125-3-naoya.horiguchi@linux.dev
>     Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
>     Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
>     Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
>     Cc: David Hildenbrand <david@redhat.com>
>     Cc: kernel test robot <lkp@intel.com>
>     Cc: Liu Shixin <liushixin2@huawei.com>
>     Cc: Muchun Song <songmuchun@bytedance.com>
>     Cc: Oscar Salvador <osalvador@suse.de>
>     Cc: Yang Shi <shy828301@gmail.com>
>     Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> 
>  arch/x86/mm/hugetlbpage.c |  8 +++++++-
>  mm/hugetlb.c              | 32 ++++++++++++++++++++++++++++++--
>  2 files changed, 37 insertions(+), 3 deletions(-)
> 

Great!  Please work with those developers to figure out why this is
causing a problem for your system.

thanks,

greg k-h