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Subject: Re: [PATCH] iommu/amd: Convert from atomic_t to refcount_t on
 device_state->count
To:     Xiyu Yang <xiyuyang19@fudan.edu.cn>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org
Cc:     yuanxzhang@fudan.edu.cn, Xin Tan <tanxin.ctf@gmail.com>
References: <1626674437-56007-1-git-send-email-xiyuyang19@fudan.edu.cn>
From:   "Suthikulpanit, Suravee" <suravee.suthikulpanit@amd.com>
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On 7/19/2021 1:00 AM, Xiyu Yang wrote:
> refcount_t type and corresponding API can protect refcounters from
> accidental underflow and overflow and further use-after-free situations.
> 
> Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
> Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
> ---
>   drivers/iommu/amd/iommu_v2.c | 11 ++++++-----
>   1 file changed, 6 insertions(+), 5 deletions(-)

Thanks,

Reviewed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>