Messages in this thread | | | Date | Wed, 27 Jun 2018 16:56:33 +0100 | From | Will Deacon <> | Subject | Re: [PATCH v4 2/3] ioremap: Update pgtable free interfaces with addr |
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Hi Toshi,
On Wed, Jun 27, 2018 at 08:13:47AM -0600, Toshi Kani wrote: > From: Chintan Pandya <cpandya@codeaurora.org> > > 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?
Will
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