IOMMU Archive on lore.kernel.org
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From: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
To: Xu Zaibo <xuzaibo@huawei.com>,
	"linux-arm-kernel@lists.infradead.org"
	<linux-arm-kernel@lists.infradead.org>,
	"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
	"linux-acpi@vger.kernel.org" <linux-acpi@vger.kernel.org>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"iommu@lists.linux-foundation.org"
	<iommu@lists.linux-foundation.org>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	"linux-mm@kvack.org" <linux-mm@kvack.org>
Cc: "bharatku@xilinx.com" <bharatku@xilinx.com>,
	"ashok.raj@intel.com" <ashok.raj@intel.com>,
	"dwmw2@infradead.org" <dwmw2@infradead.org>,
	"ilias.apalodimas@linaro.org" <ilias.apalodimas@linaro.org>,
	Will Deacon <Will.Deacon@arm.com>,
	"okaya@codeaurora.org" <okaya@codeaurora.org>,
	"rgummal@xilinx.com" <rgummal@xilinx.com>,
	"rfranz@cavium.com" <rfranz@cavium.com>,
	"liguozhu@hisilicon.com" <liguozhu@hisilicon.com>,
	"christian.koenig@amd.com" <christian.koenig@amd.com>
Subject: Re: [PATCH v2 13/40] vfio: Add support for Shared Virtual Addressing
Date: Fri, 25 May 2018 10:47:43 +0100
Message-ID: <fea420ff-e738-e2ed-ab1e-a3f4dde4b6ef@arm.com> (raw)
In-Reply-To: <5B077765.30703@huawei.com>

On 25/05/18 03:39, Xu Zaibo wrote:
> Hi,
> 
> On 2018/5/24 23:04, Jean-Philippe Brucker wrote:
>> On 24/05/18 13:35, Xu Zaibo wrote:
>>>> Right, sva_init() must be called once for any device that intends to use
>>>> bind(). For the second process though, group->sva_enabled will be true
>>>> so we won't call sva_init() again, only bind().
>>> Well, while I create mediated devices based on one parent device to support multiple
>>> processes(a new process will create a new 'vfio_group' for the corresponding mediated device,
>>> and 'sva_enabled' cannot work any more), in fact, *sva_init and *sva_shutdown are basically
>>> working on parent device, so, as a result, I just only need sva initiation and shutdown on the
>>> parent device only once. So I change the two as following:
>>>
>>> @@ -551,8 +565,18 @@ int iommu_sva_device_init(struct device *dev, unsigned long features,
>>>        if (features & ~IOMMU_SVA_FEAT_IOPF)
>>>           return -EINVAL;
>>>
>>> +    /* If already exists, do nothing  */
>>> +    mutex_lock(&dev->iommu_param->lock);
>>> +    if (dev->iommu_param->sva_param) {
>>> +        mutex_unlock(&dev->iommu_param->lock);
>>> +        return 0;
>>> +    }
>>> +    mutex_unlock(&dev->iommu_param->lock);
>>>
>>>       if (features & IOMMU_SVA_FEAT_IOPF) {
>>>           ret = iommu_register_device_fault_handler(dev, iommu_queue_iopf,
>>>
>>>
>>> @@ -621,6 +646,14 @@ int iommu_sva_device_shutdown(struct device *dev)
>>>       if (!domain)
>>>           return -ENODEV;
>>>
>>> +    /* If any other process is working on the device, shut down does nothing. */
>>> +    mutex_lock(&dev->iommu_param->lock);
>>> +    if (!list_empty(&dev->iommu_param->sva_param->mm_list)) {
>>> +        mutex_unlock(&dev->iommu_param->lock);
>>> +        return 0;
>>> +    }
>>> +    mutex_unlock(&dev->iommu_param->lock);
>> I don't think iommu-sva.c is the best place for this, it's probably
>> better to implement an intermediate layer (the mediating driver), that
>> calls iommu_sva_device_init() and iommu_sva_device_shutdown() once. Then
>> vfio-pci would still call these functions itself, but for mdev the
>> mediating driver keeps a refcount of groups, and calls device_shutdown()
>> only when freeing the last mdev.
>>
>> A device driver (non mdev in this example) expects to be able to free
>> all its resources after sva_device_shutdown() returns. Imagine the
>> mm_list isn't empty (mm_exit() is running late), and instead of waiting
>> in unbind_dev_all() below, we return 0 immediately. Then the calling
>> driver frees its resources, and the mm_exit callback along with private
>> data passed to bind() disappear. If a mm_exit() is still running in
>> parallel, then it will try to access freed data and corrupt memory. So
>> in this function if mm_list isn't empty, the only thing we can do is wait.
>>
> I still don't understand why we should 'unbind_dev_all', is it possible 
> to do a 'unbind_dev_pasid'?

Not in sva_device_shutdown(), it needs to clean up everything. For
example you want to physically unplug the device, or assign it to a VM.
To prevent any leak sva_device_shutdown() needs to remove all bonds. In
theory there shouldn't be any, since either the driver did unbind_dev(),
or all process exited. This is a safety net.

> Then we can do other things instead of waiting that user may not like. :)

They may not like it, but it's for their own good :) At the moment we're
waiting that:

* All exit_mm() callback for this device have finished. If we don't wait
  then the caller will free the private data passed to bind and the
  mm_exit() callback while they are still being used.

* All page requests targeting this device are dealt with. If we don't
  wait then some requests, that are lingering in the IOMMU PRI queue,
  may hit the next contexts bound to this device, possibly in a
  different VM. It may not be too risky (though probably exploitable in
  some way), but is incredibly messy.

All of this is bounded in time, and normally should be over pretty fast
unless the device driver's exit_mm() does something strange. If the
driver did the right thing, there shouldn't be any wait here (although
there may be one in unbind_dev() for the same reasons - prevent use
after free).

Thanks,
Jean

  reply index

Thread overview: 123+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-11 19:06 [PATCH v2 00/40] Shared Virtual Addressing for the IOMMU Jean-Philippe Brucker
     [not found] ` <20180511190641.23008-1-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-05-11 19:06   ` [PATCH v2 01/40] iommu: Introduce Shared Virtual Addressing API Jean-Philippe Brucker
     [not found]     ` <20180511190641.23008-2-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-05-16 20:41       ` Jacob Pan
2018-05-17 10:02         ` Jean-Philippe Brucker
2018-05-17 17:00           ` Jacob Pan
2018-09-05 11:29       ` Auger Eric
     [not found]         ` <bf42affd-e9d0-e4fc-6d28-f3c3f7795348-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2018-09-06 11:09           ` Jean-Philippe Brucker
     [not found]             ` <03d31ba5-1eda-ea86-8c0c-91d14c86fe83-5wv7dgnIgG8@public.gmane.org>
2018-09-06 11:12               ` Christian König
     [not found]                 ` <ed39159c-087e-7e56-7d29-d1de9fa1677f-5C7GfCeVMHo@public.gmane.org>
2018-09-06 12:45                   ` Jean-Philippe Brucker
     [not found]                     ` <f0b317d5-e2e9-5478-952c-05e8b97bd68b-5wv7dgnIgG8@public.gmane.org>
2018-09-07  8:55                       ` Christian König
     [not found]                         ` <2fd4a0a1-1a35-bf82-df84-b995cce011d9-5C7GfCeVMHo@public.gmane.org>
2018-09-07 15:45                           ` Jean-Philippe Brucker
     [not found]                             ` <65e7accd-4446-19f5-c667-c6407e89cfa6-5wv7dgnIgG8@public.gmane.org>
2018-09-07 18:02                               ` Christian König
     [not found]                                 ` <5bbc0332-b94b-75cc-ca42-a9b196811daf-5C7GfCeVMHo@public.gmane.org>
2018-09-07 21:25                                   ` Jacob Pan
2018-09-08  7:29                                     ` Christian König
     [not found]                                       ` <3e3a6797-a233-911b-3a7d-d9b549160960-5C7GfCeVMHo@public.gmane.org>
2018-09-12 12:40                                         ` Jean-Philippe Brucker
     [not found]                                           ` <9445a0be-fb5b-d195-4fdf-7ad6cb36ef4f-5wv7dgnIgG8@public.gmane.org>
2018-09-12 12:56                                             ` Christian König
2018-09-13  7:15                                     ` Tian, Kevin
2018-09-13  7:26                           ` Tian, Kevin
2018-05-11 19:06   ` [PATCH v2 02/40] iommu/sva: Bind process address spaces to devices Jean-Philippe Brucker
     [not found]     ` <20180511190641.23008-3-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-05-17 13:10       ` Jonathan Cameron
     [not found]         ` <20180517141058.00001c76-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-05-21 14:43           ` Jean-Philippe Brucker
2018-09-05 11:29       ` Auger Eric
     [not found]         ` <471873d4-a1a6-1a3a-cf17-1e686b4ade96-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2018-09-06 11:09           ` Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 03/40] iommu/sva: Manage process address spaces Jean-Philippe Brucker
     [not found]     ` <20180511190641.23008-4-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-05-16 23:31       ` Jacob Pan
2018-05-17 10:02         ` Jean-Philippe Brucker
     [not found]           ` <de478769-9f7a-d40b-a55e-e2c63ad883e8-5wv7dgnIgG8@public.gmane.org>
2018-05-22 16:43             ` Jacob Pan
2018-05-24 11:44               ` Jean-Philippe Brucker
2018-05-24 11:50                 ` Ilias Apalodimas
2018-05-24 15:04                   ` Jean-Philippe Brucker
     [not found]                     ` <19e82a74-429a-3f86-119e-32b12082d0ff-5wv7dgnIgG8@public.gmane.org>
2018-05-25  6:33                       ` Ilias Apalodimas
2018-05-25  8:39                         ` Jonathan Cameron
     [not found]                           ` <20180525093959.000040a7-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-05-26  2:24                             ` Kenneth Lee
2018-05-26  2:24                           ` Kenneth Lee
     [not found]                           ` <20180526022445.GA6069@kllp05>
2018-06-11 16:10                             ` Kenneth Lee
2018-06-11 16:10                             ` Kenneth Lee
2018-06-11 16:32                           ` Kenneth Lee
2018-05-17 14:25       ` Jonathan Cameron
     [not found]         ` <20180517150516.000067ca-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-05-21 14:44           ` Jean-Philippe Brucker
2018-09-05 12:14       ` Auger Eric
     [not found]         ` <d785ec89-6743-d0f1-1a7f-85599a033e5b-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2018-09-05 18:18           ` Jacob Pan
2018-09-06 17:40             ` Jean-Philippe Brucker
2018-09-06 11:10           ` Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 04/40] iommu/sva: Add a mm_exit callback for device drivers Jean-Philippe Brucker
     [not found]     ` <20180511190641.23008-5-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-09-05 13:23       ` Auger Eric
     [not found]         ` <d1dc28c4-7742-9c41-3f91-3fbcb8b13c1c-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2018-09-06 11:10           ` Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 05/40] iommu/sva: Track mm changes with an MMU notifier Jean-Philippe Brucker
     [not found]     ` <20180511190641.23008-6-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-05-17 14:25       ` Jonathan Cameron
     [not found]         ` <20180517152514.00004247-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-05-21 14:44           ` Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 06/40] iommu/sva: Search mm by PASID Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 07/40] iommu: Add a page fault handler Jean-Philippe Brucker
     [not found]     ` <20180511190641.23008-8-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-05-17 15:25       ` Jonathan Cameron
     [not found]         ` <20180517162555.00002bd3-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-05-21 14:48           ` Jean-Philippe Brucker
2018-05-18 18:04       ` Jacob Pan
2018-05-21 14:49         ` Jean-Philippe Brucker
     [not found]           ` <8a640794-a6f3-fa01-82a9-06479a6f779a-5wv7dgnIgG8@public.gmane.org>
2018-05-22 23:35             ` Jacob Pan
2018-05-24 11:44               ` Jean-Philippe Brucker
     [not found]                 ` <bdf9f221-ab97-2168-d072-b7f6a0dba840-5wv7dgnIgG8@public.gmane.org>
2018-05-26  0:35                   ` Jacob Pan
2018-05-29 10:00                     ` Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 08/40] iommu/iopf: Handle mm faults Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 09/40] iommu/sva: Register page fault handler Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 10/40] mm: export symbol mm_access Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 11/40] mm: export symbol find_get_task_by_vpid Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 12/40] mm: export symbol mmput_async Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 13/40] vfio: Add support for Shared Virtual Addressing Jean-Philippe Brucker
     [not found]     ` <20180511190641.23008-14-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-05-17 15:58       ` Jonathan Cameron
     [not found]         ` <20180517165845.00000cc9-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-05-21 14:51           ` Jean-Philippe Brucker
2018-05-23  9:38       ` Xu Zaibo
     [not found]         ` <5B0536A3.1000304-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-05-24 11:44           ` Jean-Philippe Brucker
     [not found]             ` <cd13f60d-b282-3804-4ca7-2d34476c597f-5wv7dgnIgG8@public.gmane.org>
2018-05-24 12:35               ` Xu Zaibo
     [not found]                 ` <5B06B17C.1090809-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-05-24 15:04                   ` Jean-Philippe Brucker
     [not found]                     ` <205c1729-8026-3efe-c363-d37d7150d622-5wv7dgnIgG8@public.gmane.org>
2018-05-25  2:39                       ` Xu Zaibo
2018-05-25  9:47                         ` Jean-Philippe Brucker [this message]
     [not found]                           ` <fea420ff-e738-e2ed-ab1e-a3f4dde4b6ef-5wv7dgnIgG8@public.gmane.org>
2018-05-26  3:53                             ` Xu Zaibo
     [not found]                               ` <5B08DA21.3070507-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-05-29 11:55                                 ` Jean-Philippe Brucker
     [not found]                                   ` <99ff4f89-86ef-a251-894c-8aa8a47d2a69-5wv7dgnIgG8@public.gmane.org>
2018-05-29 12:24                                     ` Xu Zaibo
2018-08-27  8:06       ` Xu Zaibo
     [not found]         ` <5B83B11E.7010807-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-08-31 13:34           ` Jean-Philippe Brucker
     [not found]             ` <1d5b6529-4e5a-723c-3f1b-dd5a9adb490c-5wv7dgnIgG8@public.gmane.org>
2018-09-01  2:23               ` Xu Zaibo
     [not found]                 ` <5B89F818.7060300-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-09-03 10:34                   ` Jean-Philippe Brucker
     [not found]                     ` <3a961aff-e830-64bb-b6a9-14e08de1abf5-5wv7dgnIgG8@public.gmane.org>
2018-09-04  2:12                       ` Xu Zaibo
     [not found]                         ` <5B8DEA15.7020404-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-09-04 10:57                           ` Jean-Philippe Brucker
     [not found]                             ` <bc27f902-4d12-21b7-b9e9-18bcae170503-5wv7dgnIgG8@public.gmane.org>
2018-09-05  3:15                               ` Xu Zaibo
     [not found]                                 ` <5B8F4A59.20004-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-09-05 11:02                                   ` Jean-Philippe Brucker
     [not found]                                     ` <b51107b8-a525-13ce-f4c3-d423b8502c27-5wv7dgnIgG8@public.gmane.org>
2018-09-06  7:26                                       ` Xu Zaibo
2018-05-11 19:06   ` [PATCH v2 14/40] dt-bindings: document stall and PASID properties for IOMMU masters Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 15/40] iommu/of: Add stall and pasid properties to iommu_fwspec Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 16/40] arm64: mm: Pin down ASIDs for sharing mm with devices Jean-Philippe Brucker
     [not found]     ` <20180511190641.23008-17-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-05-15 14:16       ` Catalin Marinas
     [not found]         ` <20180515141658.vivrgcyww2pxumye-+1aNUgJU5qkijLcmloz0ER/iLCjYCKR+VpNB7YpNyf8@public.gmane.org>
2018-05-17 10:01           ` Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 17/40] iommu/arm-smmu-v3: Link domains and devices Jean-Philippe Brucker
     [not found]     ` <20180511190641.23008-18-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-05-17 16:07       ` Jonathan Cameron
     [not found]         ` <20180517170748.00004927-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2018-05-21 14:49           ` Jean-Philippe Brucker
2018-09-10 15:16       ` Auger Eric
2018-05-11 19:06   ` [PATCH v2 18/40] iommu/io-pgtable-arm: Factor out ARM LPAE register defines Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 19/40] iommu: Add generic PASID table library Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 20/40] iommu/arm-smmu-v3: Move context descriptor code Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 21/40] iommu/arm-smmu-v3: Add support for Substream IDs Jean-Philippe Brucker
     [not found]     ` <20180511190641.23008-22-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-05-31 11:01       ` Bharat Kumar Gogada
     [not found]         ` <BLUPR0201MB1505AA55707BE2E13392FFAFA5630-hRBPhS1iNj/g9tdZWAsUFxrHTHEw16jenBOFsp37pqbUKgpGm//BTAC/G2K4zDHf@public.gmane.org>
2018-06-01 10:46           ` Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 22/40] iommu/arm-smmu-v3: Add second level of context descriptor table Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 23/40] iommu/arm-smmu-v3: Share process page tables Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 24/40] iommu/arm-smmu-v3: Seize private ASID Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 25/40] iommu/arm-smmu-v3: Add support for VHE Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 26/40] iommu/arm-smmu-v3: Enable broadcast TLB maintenance Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 27/40] iommu/arm-smmu-v3: Add SVA feature checking Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 28/40] iommu/arm-smmu-v3: Implement mm operations Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 29/40] iommu/arm-smmu-v3: Add support for Hardware Translation Table Update Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 30/40] iommu/arm-smmu-v3: Register I/O Page Fault queue Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 31/40] iommu/arm-smmu-v3: Improve add_device error handling Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 32/40] iommu/arm-smmu-v3: Maintain a SID->device structure Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 33/40] iommu/arm-smmu-v3: Add stall support for platform devices Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 34/40] ACPI/IORT: Check ATS capability in root complex nodes Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 35/40] iommu/arm-smmu-v3: Add support for PCI ATS Jean-Philippe Brucker
     [not found]     ` <20180511190641.23008-36-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-05-19 17:25       ` Sinan Kaya
     [not found]         ` <922474e8-0aa5-e022-0502-f1e51b0d4859-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>
2018-05-21 14:52           ` Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 36/40] iommu/arm-smmu-v3: Hook up ATC invalidation to mm ops Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 37/40] iommu/arm-smmu-v3: Disable tagged pointers Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 38/40] PCI: Make "PRG Response PASID Required" handling common Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 39/40] iommu/arm-smmu-v3: Add support for PRI Jean-Philippe Brucker
     [not found]     ` <20180511190641.23008-40-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org>
2018-05-25 14:08       ` Bharat Kumar Gogada
     [not found]         ` <BLUPR0201MB150513BBAA161355DE9B3A48A5690-hRBPhS1iNj/g9tdZWAsUFxrHTHEw16jenBOFsp37pqbUKgpGm//BTAC/G2K4zDHf@public.gmane.org>
2018-05-29 10:27           ` Jean-Philippe Brucker
2018-05-11 19:06   ` [PATCH v2 40/40] iommu/arm-smmu-v3: Add support for PCI PASID Jean-Philippe Brucker

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    --in-reply-to=fea420ff-e738-e2ed-ab1e-a3f4dde4b6ef@arm.com \
    --to=jean-philippe.brucker@arm.com \
    --cc=Will.Deacon@arm.com \
    --cc=ashok.raj@intel.com \
    --cc=bharatku@xilinx.com \
    --cc=christian.koenig@amd.com \
    --cc=devicetree@vger.kernel.org \
    --cc=dwmw2@infradead.org \
    --cc=ilias.apalodimas@linaro.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=kvm@vger.kernel.org \
    --cc=liguozhu@hisilicon.com \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=okaya@codeaurora.org \
    --cc=rfranz@cavium.com \
    --cc=rgummal@xilinx.com \
    --cc=xuzaibo@huawei.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

IOMMU Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-iommu/0 linux-iommu/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-iommu linux-iommu/ https://lore.kernel.org/linux-iommu \
		iommu@lists.linux-foundation.org
	public-inbox-index linux-iommu

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.linux-foundation.lists.iommu


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git