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Date:   Thu, 28 Apr 2022 09:35:39 -0700
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Subject: Re: [PATCH v4 05/11] iommu/sva: Assign a PASID to mm on PASID
 allocation and free it on mm exit
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To:     Jean-Philippe Brucker <jean-philippe@linaro.org>
Cc:     Fenghua Yu <fenghua.yu@intel.com>,
        Jacob Pan <jacob.jun.pan@linux.intel.com>,
        Tony Luck <tony.luck@intel.com>,
        Ashok Raj <ashok.raj@intel.com>,
        Ravi V Shankar <ravi.v.shankar@intel.com>,
        Peter Zijlstra <peterz@infradead.org>, robin.murphy@arm.com,
        Dave Hansen <dave.hansen@linux.intel.com>,
        x86 <x86@kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        iommu <iommu@lists.linux-foundation.org>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Andy Lutomirski <luto@kernel.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>, zhangfei.gao@linaro.org,
        Thomas Gleixner <tglx@linutronix.de>, will@kernel.org
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From:   Dave Hansen <dave.hansen@intel.com>
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On 4/28/22 09:01, Jean-Philippe Brucker wrote:
>> But, this misses an important point: even after the address space is
>> gone, the PASID will still be programmed into a device.  Device drivers
>> might, for instance, still need to flush operations that are outstanding
>> and need to use that PASID.  They do this at ->release() time.
> It's not really clear which release() this is. For us it's file descriptor
> release() (not MMU notifier release(), which is how I initially understood
> this sentence)

OK, maybe that should be: "file->release() time" to make it more clear.