[PATCH v7 16/23] powerpc/e500: Switch to 64 bits PGD on 85xx (32 bits)

[Guenter Roeck]

On 8/7/24 03:11, Christophe Leroy wrote:
> Hi,
> 
> Le 31/07/2024 à 18:35, Guenter Roeck a écrit :
>> On 7/31/24 08:36, LEROY Christophe wrote:
>>>
>>> Hi Guenter,
>>> Thanks for this report. I'm afk this week, i"ll have a look at it in more détails next week.
>>> But to be sûre, does that Oops match the bisected commit ? Because pmd_leaf()  for e500 doesn't exist yet so pmd_write() shouldnt be called.
>>> I did validate all my changes with mpc8544 on qemu when i implemented this séries, using map_hugetlb mm selftest. What test tool are you using ?
>>
>> Nothing special; it is just a qemu boot test with various module test and debug options enabled,
>> using a root file system generated with buildroot.
> 
> I still don't get anything with mpc85xx_defconfig.
> 
> Can you tell with debug options you use and which module tests ?
> 

As a follow-up, reverting the following sequence of patches fixes the problem for me.

01f6be2efa3e (HEAD -> fixes-v6.11) Revert "powerpc/e500: switch to 64 bits PGD on 85xx (32 bits)"
6f9971be9b8c Revert "powerpc/e500: encode hugepage size in PTE bits"
f183504567cf Revert "powerpc/e500: don't pre-check write access on data TLB error"
0a3756093805 Revert "powerpc/e500: free r10 for FIND_PTE"
8487e2021e4d Revert "powerpc/e500: use contiguous PMD instead of hugepd"
23430a37c22d Revert "powerpc/64s: use contiguous PMD/PUD instead of HUGEPD"
1af7a0fb66bf Revert "powerpc/mm: remove hugepd leftovers"
c498c53e790d Revert "mm: remove CONFIG_ARCH_HAS_HUGEPD"

I was unable to revert just a subset since they all depend on each other.

Detailed logs:

With reverts:

https://kerneltests.org/builders/qemu-ppc-testing/builds/171/steps/qemubuildcommand/logs/stdio

Without reverts:

https://kerneltests.org/builders/qemu-ppc-master/builds/249/steps/qemubuildcommand/logs/stdio

Guenter