On Tue, Jul 03, 2018 at 11:02:15PM +0200, Thomas Gleixner wrote: > On Fri, 29 Jun 2018, Kani, Toshi wrote: > > On Fri, 2018-06-29 at 13:23 +0100, Will Deacon wrote: > > > On Wed, Jun 27, 2018 at 04:13:22PM +0000, Kani, Toshi wrote: > > > > On Wed, 2018-06-27 at 16:56 +0100, Will Deacon wrote: > > > > > On Wed, Jun 27, 2018 at 08:13:47AM -0600, Toshi Kani wrote: > > > > > > From: Chintan Pandya <[email protected]> > > > > > > > > > > > > The following kernel panic was observed on ARM64 platform due to a > > > > > > stale > > > > > > TLB entry. > > > > > > > > > > > > 1. ioremap with 4K size, a valid pte page table is set. > > > > > > 2. iounmap it, its pte entry is set to 0. > > > > > > 3. ioremap the same address with 2M size, update its pmd entry with > > > > > > a new value. > > > > > > 4. CPU may hit an exception because the old pmd entry is still in > > > > > > TLB, > > > > > > which leads to a kernel panic. > > > > > > > > > > > > Commit b6bdb7517c3d ("mm/vmalloc: add interfaces to free unmapped > > > > > > page > > > > > > table") has addressed this panic by falling to pte mappings in the > > > > > > above > > > > > > case on ARM64. > > > > > > > > > > > > To support pmd mappings in all cases, TLB purge needs to be > > > > > > performed > > > > > > in this case on ARM64. > > > > > > > > > > > > Add a new arg, 'addr', to pud_free_pmd_page() and > > > > > > pmd_free_pte_page() > > > > > > so that TLB purge can be added later in seprate patches. > > > > > > > > > > So I acked v13 of Chintan's series posted here: > > > > > > > > > > http://lists.infradead.org/pipermail/linux-arm-kernel/2018-June/582953.html > > > > > > > > > > any chance this lot could all be merged together, please? > > > > > > > > Chintan's patch 2/3 and 3/3 apply cleanly on top of my series. Can you > > > > please coordinate with Thomas on the logistics? > > > > > > Sure. I guess having this series on a common branch that I can pull into > > > arm64 and apply Chintan's other patches on top would work. > > > > > > How does that sound? > > > > Should this go thru -mm tree then? > > > > Andrew, Thomas, what do you think? > > I just pick it up and provide Will a branch to pull that lot from.
Thanks, Thomas. Please let me know once you've pushed something out. Will
