IOMMU Archive on lore.kernel.org
 help / color / Atom feed
From: Jacob Pan <jacob.jun.pan@linux.intel.com>
To: Lu Baolu <baolu.lu@linux.intel.com>
Cc: "Tian, Kevin" <kevin.tian@intel.com>,
	Raj Ashok <ashok.raj@intel.com>,
	Jean-Philippe Brucker <jean-philippe.brucker@arm.com>,
	iommu@lists.linux-foundation.org,
	LKML <linux-kernel@vger.kernel.org>,
	Alex Williamson <alex.williamson@redhat.com>,
	Andriy Shevchenko <andriy.shevchenko@linux.intel.com>,
	David Woodhouse <dwmw2@infradead.org>
Subject: Re: [PATCH v4 20/22] iommu/vt-d: Add bind guest PASID support
Date: Wed, 14 Aug 2019 10:20:32 -0700
Message-ID: <20190814102032.5265e1da@jacob-builder> (raw)
In-Reply-To: <840a6943-87ab-938f-5f8d-3a2c21e08549@linux.intel.com>

On Fri, 5 Jul 2019 10:21:27 +0800
Lu Baolu <baolu.lu@linux.intel.com> wrote:

> Hi Jacob,
> 
> On 6/28/19 4:22 AM, Jacob Pan wrote:
> >>> +		}
> >>> +		refcount_set(&svm->refs, 0);
> >>> +		ioasid_set_data(data->hpasid, svm);
> >>> +		INIT_LIST_HEAD_RCU(&svm->devs);
> >>> +		INIT_LIST_HEAD(&svm->list);
> >>> +
> >>> +		mmput(svm->mm);
> >>> +	}
> >>> +	sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
> >>> +	if (!sdev) {
> >>> +		ret = -ENOMEM;
> >>> +		goto out;  
> >> I think you need to clean up svm if its device list is empty here,
> >> as you said above:
> >>  
> > No, we come here only if the device list is not empty and the new
> > device to bind is different than any existing device in the list.
> > If we cannot allocate memory for the new device, should not free
> > the existing SVM, right?
> >   
> 
> I'm sorry, but the code doesn't show this. We come here even an svm
> data structure was newly created with an empty device list. I post
> the code below to ensure that we are reading a same piece of code.
> 
Sorry for the delay. You are right, I need to clean up svm if device
list is empty.

Thanks!
>          mutex_lock(&pasid_mutex);
>          svm = ioasid_find(NULL, data->hpasid, NULL);
>          if (IS_ERR(svm)) {
>                  ret = PTR_ERR(svm);
>                  goto out;
>          }
>          if (svm) {
>                  /*
>                   * If we found svm for the PASID, there must be at
>                   * least one device bond, otherwise svm should be
> freed. */
>                  BUG_ON(list_empty(&svm->devs));
> 
>                  for_each_svm_dev() {
>                          /* In case of multiple sub-devices of the
> same pdev assigned, we should
>                           * allow multiple bind calls with the same 
> PASID and pdev.
>                           */
>                          sdev->users++;
>                          goto out;
>                  }
>          } else {
>                  /* We come here when PASID has never been bond to a 
> device. */
>                  svm = kzalloc(sizeof(*svm), GFP_KERNEL);
>                  if (!svm) {
>                          ret = -ENOMEM;
>                          goto out;
>                  }
>                  /* REVISIT: upper layer/VFIO can track host process 
> that bind the PASID.
>                   * ioasid_set = mm might be sufficient for vfio to 
> check pasid VMM
>                   * ownership.
>                   */
>                  svm->mm = get_task_mm(current);
>                  svm->pasid = data->hpasid;
>                  if (data->flags & IOMMU_SVA_GPASID_VAL) {
>                          svm->gpasid = data->gpasid;
>                          svm->flags &= SVM_FLAG_GUEST_PASID;
>                  }
>                  refcount_set(&svm->refs, 0);
>                  ioasid_set_data(data->hpasid, svm);
>                  INIT_LIST_HEAD_RCU(&svm->devs);
>                  INIT_LIST_HEAD(&svm->list);
> 
>                  mmput(svm->mm);
>          }
>          sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
>          if (!sdev) {
>                  ret = -ENOMEM;
>                  goto out;
>          }
>          sdev->dev = dev;
>          sdev->users = 1;
> 
> Best regards,
> Baolu

[Jacob Pan]
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

  reply index

Thread overview: 64+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-09 13:44 [PATCH v4 00/22] Shared virtual address IOMMU and VT-d support Jacob Pan
2019-06-09 13:44 ` [PATCH v4 01/22] driver core: Add per device iommu param Jacob Pan
2019-06-09 13:44 ` [PATCH v4 02/22] iommu: Introduce device fault data Jacob Pan
2019-06-18 15:42   ` Jonathan Cameron
2019-06-09 13:44 ` [PATCH v4 03/22] iommu: Introduce device fault report API Jacob Pan
2019-06-18 15:41   ` Jonathan Cameron
2019-06-09 13:44 ` [PATCH v4 04/22] iommu: Add recoverable fault reporting Jacob Pan
2019-06-18 15:44   ` Jonathan Cameron
2019-06-09 13:44 ` [PATCH v4 05/22] iommu: Add a timeout parameter for PRQ response Jacob Pan
2019-06-09 13:44 ` [PATCH v4 06/22] trace/iommu: Add sva trace events Jacob Pan
2019-06-09 13:44 ` [PATCH v4 07/22] iommu: Use device fault trace event Jacob Pan
2019-06-09 13:44 ` [PATCH v4 08/22] iommu: Introduce attach/detach_pasid_table API Jacob Pan
2019-06-18 15:41   ` Jonathan Cameron
2019-06-24 15:06     ` Auger Eric
2019-06-24 15:23       ` Jean-Philippe Brucker
2019-06-09 13:44 ` [PATCH v4 09/22] iommu: Introduce cache_invalidate API Jacob Pan
2019-06-18 15:41   ` Jonathan Cameron
2019-06-09 13:44 ` [PATCH v4 10/22] iommu: Fix compile error without IOMMU_API Jacob Pan
2019-06-18 14:10   ` Jonathan Cameron
2019-06-24 22:28     ` Jacob Pan
2019-06-09 13:44 ` [PATCH v4 11/22] iommu: Introduce guest PASID bind function Jacob Pan
2019-06-18 15:36   ` Jean-Philippe Brucker
2019-06-24 22:24     ` Jacob Pan
2019-07-16 16:44   ` Auger Eric
2019-08-05 21:02     ` Jacob Pan
2019-08-05 23:13     ` Jacob Pan
2019-06-09 13:44 ` [PATCH v4 12/22] iommu: Add I/O ASID allocator Jacob Pan
2019-06-18 16:50   ` Jonathan Cameron
2019-06-25 18:55     ` Jacob Pan
2019-06-09 13:44 ` [PATCH v4 13/22] iommu/vt-d: Enlightened PASID allocation Jacob Pan
2019-07-16  9:29   ` Auger Eric
2019-08-13 16:57     ` Jacob Pan
2019-06-09 13:44 ` [PATCH v4 14/22] iommu/vt-d: Add custom allocator for IOASID Jacob Pan
2019-07-16  9:30   ` Auger Eric
2019-08-05 20:02     ` Jacob Pan
2019-06-09 13:44 ` [PATCH v4 15/22] iommu/vt-d: Replace Intel specific PASID allocator with IOASID Jacob Pan
2019-06-18 15:57   ` Jonathan Cameron
2019-06-24 21:36     ` Jacob Pan
2019-06-27  1:53   ` Lu Baolu
2019-06-27 15:40     ` Jacob Pan
2019-06-09 13:44 ` [PATCH v4 16/22] iommu/vt-d: Move domain helper to header Jacob Pan
2019-07-16  9:33   ` Auger Eric
2019-06-09 13:44 ` [PATCH v4 17/22] iommu/vt-d: Avoid duplicated code for PASID setup Jacob Pan
2019-06-18 16:03   ` Jonathan Cameron
2019-06-24 23:44     ` Jacob Pan
2019-07-16  9:52   ` Auger Eric
2019-06-09 13:44 ` [PATCH v4 18/22] iommu/vt-d: Add nested translation helper function Jacob Pan
2019-06-09 13:44 ` [PATCH v4 19/22] iommu/vt-d: Clean up for SVM device list Jacob Pan
2019-06-18 16:42   ` Jonathan Cameron
2019-06-24 23:59     ` Jacob Pan
2019-06-09 13:44 ` [PATCH v4 20/22] iommu/vt-d: Add bind guest PASID support Jacob Pan
2019-06-18 16:44   ` Jonathan Cameron
2019-06-24 22:41     ` Jacob Pan
2019-06-27  2:50   ` Lu Baolu
2019-06-27 20:22     ` Jacob Pan
2019-07-05  2:21       ` Lu Baolu
2019-08-14 17:20         ` Jacob Pan [this message]
2019-07-16 16:45   ` Auger Eric
2019-07-16 17:04     ` Raj, Ashok
2019-07-18  7:47       ` Auger Eric
2019-06-09 13:44 ` [PATCH v4 21/22] iommu/vt-d: Support flushing more translation cache types Jacob Pan
2019-07-18  8:35   ` Auger Eric
2019-08-14 20:17     ` Jacob Pan
2019-06-09 13:44 ` [PATCH v4 22/22] iommu/vt-d: Add svm/sva invalidate function Jacob Pan

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190814102032.5265e1da@jacob-builder \
    --to=jacob.jun.pan@linux.intel.com \
    --cc=alex.williamson@redhat.com \
    --cc=andriy.shevchenko@linux.intel.com \
    --cc=ashok.raj@intel.com \
    --cc=baolu.lu@linux.intel.com \
    --cc=dwmw2@infradead.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=jean-philippe.brucker@arm.com \
    --cc=kevin.tian@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    /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