On 5/24/2018 5:01 PM, Suzuki K Poulose Wrote: > On 24/05/18 09:50, Jia He wrote: >> Hi Suzuki >> >> On 5/24/2018 4:44 PM, Suzuki K Poulose Wrote: >>> On 14/05/18 10:45, Suzuki K Poulose wrote: >>>> On 10/05/18 00:31, Andrew Morton wrote: >>>>> On Fri, 4 May 2018 11:11:46 +0800 Jia He <hejianet@xxxxxxxxx> wrote: >>>>> >>>>>> In our armv8a server(QDF2400), I noticed lots of WARN_ON caused by PAGE_SIZE >>>>>> unaligned for rmap_item->address under memory pressure tests(start 20 guests >>>>>> and run memhog in the host). >>>>>> >>>>>> ... >>>>>> >>>>>> In rmap_walk_ksm, the rmap_item->address might still have the STABLE_FLAG, >>>>>> then the start and end in handle_hva_to_gpa might not be PAGE_SIZE aligned. >>>>>> Thus it will cause exceptions in handle_hva_to_gpa on arm64. >>>>>> >>>>>> This patch fixes it by ignoring(not removing) the low bits of address when >>>>>> doing rmap_walk_ksm. >>>>>> >>>>>> Signed-off-by: jia.he@xxxxxxxxxxxxxxxx >>>>> >>>>> I assumed you wanted this patch to be committed as >>>>> From:jia.he@xxxxxxxxxxxxxxxx rather than From:hejianet@xxxxxxxxx, so I >>>>> made that change. Please let me know if this was inappropriate. >>>>> >>>>> You can do this yourself by adding an explicit From: line to the very >>>>> start of the patch's email text. >>>>> >>>>> Also, a storm of WARN_ONs is pretty poor behaviour. Is that the only >>>>> misbehaviour which this bug causes? Do you think the fix should be >>>>> backported into earlier kernels? >>>>> >>> >>> >>> Jia, Andrew, >>> >>> What is the status of this patch ? >>> >>> Suzuki >> I thought the patch is merged into mmotm tree. >> http://www.ozlabs.org/~akpm/mmotm/series >> But I don't know what is the next step. > > Hi Jia, > > Thanks for the update. I think that should eventually hit mainline. When it does, > please could you send the patch to stable kernel versions too ? > > Usually having a "Cc: stable@xxxxxxxxxxxxxxx" in the original patch (for > critical fixes) would have done the trick. But since we don't have it, > please send it following the stable kernel rules. > > Cheers > Suzuki > Ok,thanks for pointing -- Cheers, Jia
