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Subject: Re: [bug report] iommu_dma_unmap_sg() is very slow then running IO
 from remote numa node
To:     Ming Lei <ming.lei@redhat.com>
CC:     Robin Murphy <robin.murphy@arm.com>,
        <iommu@lists.linux-foundation.org>, Will Deacon <will@kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-nvme@lists.infradead.org>, <linux-kernel@vger.kernel.org>
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From:   John Garry <john.garry@huawei.com>
Message-ID: <74537f9c-af5f-cd84-60ab-49ca6220310e@huawei.com>
Date:   Wed, 21 Jul 2021 10:23:38 +0100
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On 21/07/2021 02:40, Ming Lei wrote:
>> I think that you should see a significant performance boost.
> There is build issue, please check your tree:
> 
>    MODPOST vmlinux.symvers
>    MODINFO modules.builtin.modinfo
>    GEN     modules.builtin
>    LD      .tmp_vmlinux.btf
> ld: Unexpected GOT/PLT entries detected!
> ld: Unexpected run-time procedure linkages detected!
> ld: drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.o: in function `smmu_test_store':
> /root/git/linux/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c:3892: undefined reference to `smmu_test_core'
>    BTF     .btf.vmlinux.bin.o
> pahole: .tmp_vmlinux.btf: No such file or directory
>    LD      .tmp_vmlinux.kallsyms1
> .btf.vmlinux.bin.o: file not recognized: file format not recognized
> make: *** [Makefile:1177: vmlinux] Error 1

Ah, sorry. I had some test code which was not properly guarded with 
necessary build switches.

I have now removed that from the tree, so please re-pull.

Thanks,
John