Re: [PATCH v4 00/16] Overhaul multi-page lookups for THP

From: Marek Szyprowski
Date: Thu Dec 03 2020 - 12:28:32 EST


Hi

On 03.12.2020 16:46, Marek Szyprowski wrote:
> On 25.11.2020 03:32, Matthew Wilcox wrote:
>> On Tue, Nov 17, 2020 at 11:43:02PM +0000, Matthew Wilcox wrote:
>>> On Tue, Nov 17, 2020 at 07:15:13PM +0000, Matthew Wilcox wrote:
>>>> I find both of these functions exceptionally confusing.  Does this
>>>> make it easier to understand?
>>> Never mind, this is buggy.  I'll send something better tomorrow.
>> That took a week, not a day.  *sigh*.  At least this is shorter.
>>
>> commit 1a02863ce04fd325922d6c3db6d01e18d55f966b
>> Author: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
>> Date:   Tue Nov 17 10:45:18 2020 -0500
>>
>>      fix mm-truncateshmem-handle-truncates-that-split-thps.patch
>
> This patch landed in todays linux-next (20201203) as commit
> 8678b27f4b8b ("8678b27f4b8bfc130a13eb9e9f27171bcd8c0b3b"). Sadly it
> breaks booting of ANY of my ARM 32bit test systems, which use initrd.
> ARM64bit based systems boot fine. Here is example of the crash:

One more thing. Reverting those two:

1b1aa968b0b6 mm-truncateshmem-handle-truncates-that-split-thps-fix-fix

8678b27f4b8b mm-truncateshmem-handle-truncates-that-split-thps-fix

on top of linux next-20201203 fixes the boot issues.

Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland