28 Apr
2018
28 Apr
'18
8:54 p.m.
On Sat, 2018-04-28 at 11:02 +0200, joro@8bytes.org wrote:
On Fri, Apr 27, 2018 at 02:31:51PM +0000, Kani, Toshi wrote:
So, we can add the step 2 on top of this patch.
- Clear pud/pmd entry.
- System wide TLB flush <-- TO BE ADDED BY NEW PATCH
- Free its underlining pmd/pte page.
This still lacks the page-table synchronization and will thus not fix the BUG_ON being triggered.
The BUG_ON issue is specific to PAE that it syncs at the pmd level. x86/64 does not have this issue since it syncs at the pgd or p4d level.
We do not need to revert this patch. We can make the above change I mentioned.
Please note that we are not in the merge window anymore and that any fix needs to be simple and obviously correct.
Understood. Changing the x86/32 sync point is risky. So, I am going to revert the free page handling for PAE.
Thanks, -Toshi