Hi Stephen,
On Thu, Jul 21, 2022 at 08:45:17PM +1000, Stephen Rothwell wrote:
> On Thu, 21 Jul 2022 09:45:12 +1000 Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> wrote:
> >
> > Today's linux-next merge of the arm64 tree got a conflict in:
> >
> > arch/arm64/kernel/head.S
> >
> > between commit:
> >
> > f7b4c3b82e7d ("arm64: set UXN on swapper page tables")
> >
> > from the arm64-fixes tree and commits:
> >
> > e42ade29e3bc ("arm64: head: split off idmap creation code")
> > c3cee924bd85 ("arm64: head: cover entire kernel image in initial ID map")
> >
> > from the arm64 tree.
> >
> > I didn't know if the change from the former was still needed after the
> > changes in the latter, so I left it out for now.
>
> OK, so my arm64 defconfig build produced these errors:
>
> arch/arm64/kernel/head.S: Assembler messages:
> arch/arm64/kernel/head.S:334: Error: immediate cannot be moved by a single instruction
> arch/arm64/kernel/head.S:343: Error: immediate cannot be moved by a single instruction
> arch/arm64/kernel/head.S:354: Error: immediate cannot be moved by a single instruction
> arch/arm64/kernel/head.S:379: Error: immediate cannot be moved by a single instruction
> arch/arm64/mm/proc.S:296: Error: immediate cannot be moved by a single instruction
>
> So I tried this patch:
>
> From: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
> Date: Thu, 21 Jul 2022 20:21:36 +1000
> Subject: [PATCH] fixup for "arm64: set UXN on swapper page tables"
>
> Signed-off-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
> ---
> arch/arm64/kernel/head.S | 8 ++++----
> arch/arm64/mm/proc.S | 2 +-
> 2 files changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
> index cefe6a73ee54..aa7c58689f68 100644
> --- a/arch/arm64/kernel/head.S
> +++ b/arch/arm64/kernel/head.S
> @@ -331,7 +331,7 @@ SYM_FUNC_START_LOCAL(create_idmap)
> adrp x0, init_idmap_pg_dir
> adrp x3, _text
> adrp x6, _end + MAX_FDT_SIZE + SWAPPER_BLOCK_SIZE
> - mov x7, SWAPPER_RX_MMUFLAGS
> + mov_q x7, SWAPPER_RX_MMUFLAGS
[...]
I think Marc posted something similar here:
https://lore.kernel.org/r/20220721124244.903567-1-maz@xxxxxxxxxx
but in further discussion offline (and echoed on that thread), we've decided
to drop f7b4c3b82e7d ("arm64: set UXN on swapper page tables") for now; the
issue it addresses doesn't affect the hardware which is readily available at
the moment so we'll just get it into -stable instead rather than disrupt
everything at this stage in the release cycle.
> So I gave up and left arm64 broken for today :-(
No problem, thank you for trying and hopefully it will be better tomorrow
once we've dropped that commit.
Will
