Re: [PATCH v5 04/18] sparc32: mm: Reduce allocation size for PMD and PTE tables

[Guenter Roeck]

On Mon, May 18, 2020 at 10:15:11PM +0300, Mike Rapoport wrote:
> On Mon, May 18, 2020 at 11:09:46AM -0700, Guenter Roeck wrote:
> > On 5/18/20 7:23 AM, Mike Rapoport wrote:
> > 
> > Below is another set of bisect results, from next-20200518. It points to one
> > of your commits. This is for microblaze (big endian) boot failures.
> 
> The microblaze one was easy, as for sparc32 I still have no clue for the
> root cause :(
> 
> Andrew, can you please fold it into "mm: pgtable: add shortcuts for
> accessing kernel PMD and PTE"? 
> 
> From 167250de28aa526342641b2647294a755d234090 Mon Sep 17 00:00:00 2001
> From: Mike Rapoport <rppt@xxxxxxxxxxxxx>
> Date: Mon, 18 May 2020 22:08:10 +0300
> Subject: [PATCH] microblaze: fix page table traversal in setup_rt_frame()
> 
> The replacement of long folded page table traversal with the direct access
> to PMD entry wrongly used the kernel page table in setup_rt_frame()
> function instead of the process (current->mm) page table.
> 
> Fix it.
> 
> Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>

Tested-by: Guenter Roeck <linux@xxxxxxxxxxxx>

> ---
>  arch/microblaze/kernel/signal.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/microblaze/kernel/signal.c b/arch/microblaze/kernel/signal.c
> index 28b1ec4b4e79..bdd6d0c86e16 100644
> --- a/arch/microblaze/kernel/signal.c
> +++ b/arch/microblaze/kernel/signal.c
> @@ -194,7 +194,7 @@ static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
>  
>  	address = ((unsigned long)frame->tramp);
>  #ifdef CONFIG_MMU
> -	pmdp = pmd_off_k(address);
> +	pmdp = pmd_off(current->mm, address);
>  
>  	preempt_disable();
>  	ptep = pte_offset_map(pmdp, address);
> -- 
> 2.26.2
> 
> 
> > Guenter
> > 
> > ---
> 
> -- 
> Sincerely yours,
> Mike.