All of lore.kernel.org
 help / color / mirror / Atom feed
From: Joerg Roedel <joro@8bytes.org>
To: Lu Baolu <baolu.lu@linux.intel.com>
Cc: iommu@lists.linux-foundation.org, jroedel@suse.de,
	linux-kernel@vger.kernel.org, Tom Murphy <murphyt7@tcd.ie>
Subject: Re: [PATCH] iommu: Implement deferred domain attachment
Date: Fri, 15 May 2020 16:20:48 +0200	[thread overview]
Message-ID: <20200515142047.GX18353@8bytes.org> (raw)
In-Reply-To: <8ce93a10-2ce0-e5a0-88a0-5d21d7003c0f@linux.intel.com>

On Fri, May 15, 2020 at 09:51:03PM +0800, Lu Baolu wrote:
> On 2020/5/15 17:45, Joerg Roedel wrote:
> >   struct iommu_domain *iommu_get_dma_domain(struct device *dev)
> >   {
> > -	return dev->iommu_group->default_domain;
> > +	struct iommu_domain *domain = dev->iommu_group->default_domain;
> > +
> > +	if (__iommu_is_attach_deferred(domain, dev))
> > +		__iommu_attach_device_no_defer(domain, dev);
> 
> It seems that the return value needs to be checked. The default domain
> is invalid if attach() failed.

True, I looked at that, the callers can't handle returning NULL here, so
I kept it this way for now. The outcome is that DMA will fail, but
otherwise we'd see a NULL-ptr dereference really quickly after returning
from that function.

Bottom line: This needs to be cleaned up separatly.

Regards,

	Joerg
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

WARNING: multiple messages have this Message-ID (diff)
From: Joerg Roedel <joro@8bytes.org>
To: Lu Baolu <baolu.lu@linux.intel.com>
Cc: iommu@lists.linux-foundation.org, jroedel@suse.de,
	linux-kernel@vger.kernel.org, Tom Murphy <murphyt7@tcd.ie>
Subject: Re: [PATCH] iommu: Implement deferred domain attachment
Date: Fri, 15 May 2020 16:20:48 +0200	[thread overview]
Message-ID: <20200515142047.GX18353@8bytes.org> (raw)
In-Reply-To: <8ce93a10-2ce0-e5a0-88a0-5d21d7003c0f@linux.intel.com>

On Fri, May 15, 2020 at 09:51:03PM +0800, Lu Baolu wrote:
> On 2020/5/15 17:45, Joerg Roedel wrote:
> >   struct iommu_domain *iommu_get_dma_domain(struct device *dev)
> >   {
> > -	return dev->iommu_group->default_domain;
> > +	struct iommu_domain *domain = dev->iommu_group->default_domain;
> > +
> > +	if (__iommu_is_attach_deferred(domain, dev))
> > +		__iommu_attach_device_no_defer(domain, dev);
> 
> It seems that the return value needs to be checked. The default domain
> is invalid if attach() failed.

True, I looked at that, the callers can't handle returning NULL here, so
I kept it this way for now. The outcome is that DMA will fail, but
otherwise we'd see a NULL-ptr dereference really quickly after returning
from that function.

Bottom line: This needs to be cleaned up separatly.

Regards,

	Joerg

  reply	other threads:[~2020-05-15 14:21 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-15  9:45 [PATCH] iommu: Implement deferred domain attachment Joerg Roedel
2020-05-15  9:45 ` Joerg Roedel
2020-05-15 13:51 ` Lu Baolu
2020-05-15 13:51   ` Lu Baolu
2020-05-15 14:20   ` Joerg Roedel [this message]
2020-05-15 14:20     ` Joerg Roedel
2020-05-15 15:42 ` Robin Murphy
2020-05-15 15:42   ` Robin Murphy
2020-05-15 16:14   ` Joerg Roedel
2020-05-15 16:14     ` Joerg Roedel
2020-05-15 16:28     ` Robin Murphy
2020-05-15 16:28       ` Robin Murphy
2020-05-15 18:26       ` Joerg Roedel
2020-05-15 18:26         ` Joerg Roedel
2020-05-15 19:23         ` Robin Murphy
2020-05-15 19:23           ` Robin Murphy
2020-05-18 13:26           ` Joerg Roedel
2020-05-18 13:26             ` Joerg Roedel
2020-05-18 22:15             ` Jerry Snitselaar
2020-05-18 22:15               ` Jerry Snitselaar
2020-05-19  7:09             ` Jerry Snitselaar
2020-05-19  7:09               ` Jerry Snitselaar

Reply instructions:

You may reply publicly 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=20200515142047.GX18353@8bytes.org \
    --to=joro@8bytes.org \
    --cc=baolu.lu@linux.intel.com \
    --cc=iommu@lists.linux-foundation.org \
    --cc=jroedel@suse.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=murphyt7@tcd.ie \
    /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
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.