Linux IOMMU Development
 help / color / mirror / Atom feed
From: Jason Gunthorpe <jgg@ziepe.ca>
To: Nicolin Chen <nicolinc@nvidia.com>
Cc: Pranjal Shrivastava <praan@google.com>,
	Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
	Robin Murphy <robin.murphy@arm.com>,
	Mostafa Saleh <smostafa@google.com>,
	iommu@lists.linux.dev, Daniel Mentz <danielmentz@google.com>
Subject: Re: [PATCH v3 1/2] iommu/arm-smmu-v3: Print better events records
Date: Wed, 2 Oct 2024 10:57:28 -0300	[thread overview]
Message-ID: <20241002135728.GD1369530@ziepe.ca> (raw)
In-Reply-To: <Zvr4vmU7u2BY3MLM@Asurada-Nvidia>

On Mon, Sep 30, 2024 at 12:15:10PM -0700, Nicolin Chen wrote:
> > +static void arm_smmu_get_evt_info(struct arm_smmu_device *smmu, u64 *evt,
> > +                                 struct arm_smmu_event *event)
> > +{
> > +       mutex_lock(&smmu->streams_mutex);
> > +       event->master = arm_smmu_find_master(smmu, event->sid);
> > +       mutex_unlock(&smmu->streams_mutex);
> > +
> > +       if (event->master)
> > +               event->master_name = dev_name(event->master->dev);
> > +       else
> > +               event->master_name = "(unassigned sid)";
> 
> Likely safer for dev_name to be in the mutex too.

The result of arm_smmu_find_master() should not leave the lock, and
dev_name()'s result can't leave the lock either, at least not with out
some refcounting on the struct device.

Jason

  parent reply	other threads:[~2024-10-02 13:57 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-09-28  0:51 [PATCH v3 0/2] Parse out event records Pranjal Shrivastava
2024-09-28  0:51 ` [PATCH v3 1/2] iommu/arm-smmu-v3: Print better events records Pranjal Shrivastava
2024-09-30 19:15   ` Nicolin Chen
2024-10-01 20:52     ` Pranjal Shrivastava
2024-10-01 23:04       ` Nicolin Chen
2024-10-02 13:57     ` Jason Gunthorpe [this message]
2024-10-02 16:55       ` Nicolin Chen
2024-10-02 17:10         ` Jason Gunthorpe
2024-10-02 17:22           ` Nicolin Chen
2024-10-03 21:26             ` Pranjal Shrivastava
2024-10-03 22:50               ` Nicolin Chen
2024-10-11  7:53                 ` Pranjal Shrivastava
2024-10-11 10:02                   ` Pranjal Shrivastava
2024-09-28  0:51 ` [PATCH v3 2/2] iommu/arm-smmu-v3: Adopt arm_smmu_event in handlers Pranjal Shrivastava
2024-09-30 19:32   ` Nicolin Chen
2024-10-01 21:02     ` Pranjal Shrivastava
2024-10-01 22:59       ` Nicolin Chen
2024-10-03 21:34         ` Pranjal Shrivastava
2024-10-03 22:53           ` Nicolin Chen
2024-10-11  7:55             ` Pranjal Shrivastava
2024-10-11 10:21               ` Robin Murphy
2024-10-11 10:45                 ` Pranjal Shrivastava
2024-10-11 11:06                   ` Pranjal Shrivastava
2024-10-11 12:59                     ` Robin Murphy
2024-10-11 20:31                       ` Pranjal Shrivastava
2024-10-15 18:34                       ` Pranjal Shrivastava
2024-10-15 20:03                         ` Robin Murphy
2024-10-17  8:06                           ` Pranjal Shrivastava

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=20241002135728.GD1369530@ziepe.ca \
    --to=jgg@ziepe.ca \
    --cc=danielmentz@google.com \
    --cc=iommu@lists.linux.dev \
    --cc=joro@8bytes.org \
    --cc=nicolinc@nvidia.com \
    --cc=praan@google.com \
    --cc=robin.murphy@arm.com \
    --cc=smostafa@google.com \
    --cc=will@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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox