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To:     <linux-kernel@vger.kernel.org>
CC:     Marc Zyngier <marc.zyngier@arm.com>,
        Christoffer Dall <christoffer.dall@arm.com>,
        wanghaibin 00208455 <wanghaibin.wang@huawei.com>
From:   Heyi Guo <guoheyi@huawei.com>
Subject: Why do we mark vpending table as non-shareable in GICR_VPENDBASER?
Message-ID: <fbee07c9-ec3b-d443-2132-7208dae38539@huawei.com>
Date:   Thu, 9 May 2019 15:10:09 +0800
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Hi Marc,

We can see in its_vpe_schedule() the shareability bits of GICR_VPENDBASER are set as non-shareable, But we set physical PENDBASER as inner-shareable. Is there any special reason for doing this? If it is because the vpending table is GICR specific, why don't we do the same for physical pending table?

We have not seen function issue with this setting, but a special detector in our hardware warns us that there are non-shareable requests sent out while some inner shareable cache entries still present in the cache, and it may cause data inconsistent.

Thanks,

Heyi