BUG: crash in __tlb_remove_page_size with STRICT_KERNEL_RWX on BOOK3S_32

[Christophe Leroy]

Le 26/04/2019 à 06:54, Serge Belyshev a écrit :
> Hi! Commit 63b2bc61956 aka "powerpc/mm/32s: Use BATs for STRICT_KERNEL_RWX"
> caused my old powerbook to crash under I/O.  After "dd if=/dev/hda of=/null"
> the crash happens in seconds.  Reverting the commit helps, as well as
> disabling STRICT_KERNEL_RWX.  Unfortunately, I was unable to capture the oops
> via the usb serial console, as it stuck right after the first "BUG: Unable to
> handle kernel data access at 0xe0c29000" message. Oops screenshot:
> http://aargh.no-ip.org/oops.jpg
> 

Hi Serge,

Could you please compile your kernel with CONFIG_PPC_PTDUMP, and provide 
the content of:

/sys/kernel/debug/kernel_page_tables
/sys/kernel/debug/powerpc/block_address_translation
/sys/kernel/debug/powerpc/segment_registers

Please also provide the begining of 'dmesg' that shows the memory layout.

Thanks
Christophe