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

[Mike Rapoport]

On Mon, May 18, 2020 at 09:37:15AM +0100, Will Deacon wrote:
> On Sat, May 16, 2020 at 05:07:50PM -0700, Guenter Roeck wrote:
> > On Sat, May 16, 2020 at 05:00:50PM -0700, Guenter Roeck wrote:
> > > On Mon, May 11, 2020 at 09:41:36PM +0100, Will Deacon wrote:
> > > > Now that the page table allocator can free page table allocations
> > > > smaller than PAGE_SIZE, reduce the size of the PMD and PTE allocations
> > > > to avoid needlessly wasting memory.
> > > > 
> > > > Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> > > > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> > > > Signed-off-by: Will Deacon <will@xxxxxxxxxx>
> > > 
> > > Something in the sparc32 patches in linux-next causes all my sparc32 emulations
> > > to crash. bisect points to this patch, but reverting it doesn't help, and neither
> > > does reverting the rest of the series.
> > > 
> > Actually, turns out I see the same pattern (lots of scheduling while atomic
> > followed by 'killing interrupt handler' in cryptomgr_test) with several
> > powerpc boot tests.  I am currently bisecting those crashes. I'll report
> > the results here as well as soon as I have it.
> 
> FWIW, I retested my sparc32 patches with PREEMPT=y and I don't see any
> issues. However, linux-next is a different story, where I don't get very far
> at all:
> 
> BUG: Bad page state in process swapper  pfn:005b4
> 
> If you're seeing this on powerpc too, I wonder if it's related to:
> 
> https://lore.kernel.org/r/20200514170327.31389-1-rppt@xxxxxxxxxx
> 
> since I think it just hit -next and the diffstat is all over the place. I've
> added Mike to CC just in case.

Thanks, Will, I'll take a look.

> Will

-- 
Sincerely yours,
Mike.