linux-kernel - RE: [PATCH v6 07/14] iommufd/viommu: Add iommufd_viommu_report

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <BN9PR11MB52766CE9C579D3EE1CE1A7058CC52@BN9PR11MB5276.namprd11.prod.outlook.com>
Date: Wed, 19 Feb 2025 06:58:16 +0000
From: "Tian, Kevin" <kevin.tian@...el.com>
To: Jason Gunthorpe <jgg@...dia.com>, Nicolin Chen <nicolinc@...dia.com>
CC: "corbet@....net" <corbet@....net>, "will@...nel.org" <will@...nel.org>,
	"joro@...tes.org" <joro@...tes.org>, "suravee.suthikulpanit@....com"
	<suravee.suthikulpanit@....com>, "robin.murphy@....com"
	<robin.murphy@....com>, "dwmw2@...radead.org" <dwmw2@...radead.org>,
	"baolu.lu@...ux.intel.com" <baolu.lu@...ux.intel.com>, "shuah@...nel.org"
	<shuah@...nel.org>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>, "iommu@...ts.linux.dev"
	<iommu@...ts.linux.dev>, "linux-arm-kernel@...ts.infradead.org"
	<linux-arm-kernel@...ts.infradead.org>, "linux-kselftest@...r.kernel.org"
	<linux-kselftest@...r.kernel.org>, "linux-doc@...r.kernel.org"
	<linux-doc@...r.kernel.org>, "eric.auger@...hat.com" <eric.auger@...hat.com>,
	"jean-philippe@...aro.org" <jean-philippe@...aro.org>, "mdf@...nel.org"
	<mdf@...nel.org>, "mshavit@...gle.com" <mshavit@...gle.com>,
	"shameerali.kolothum.thodi@...wei.com"
	<shameerali.kolothum.thodi@...wei.com>, "smostafa@...gle.com"
	<smostafa@...gle.com>, "ddutile@...hat.com" <ddutile@...hat.com>, "Liu, Yi L"
	<yi.l.liu@...el.com>, "patches@...ts.linux.dev" <patches@...ts.linux.dev>
Subject: RE: [PATCH v6 07/14] iommufd/viommu: Add iommufd_viommu_report_event
 helper

> From: Jason Gunthorpe <jgg@...dia.com>
> Sent: Tuesday, February 18, 2025 11:36 PM
> 
> On Fri, Jan 24, 2025 at 04:30:36PM -0800, Nicolin Chen wrote:
> > +int iommufd_viommu_report_event(struct iommufd_viommu *viommu,
> > +				enum iommu_veventq_type type, void
> *event_data,
> > +				size_t data_len)
> > +{
> > +	struct iommufd_veventq *veventq;
> > +	struct iommufd_vevent *vevent;
> > +	int rc = 0;
> > +
> > +	if (WARN_ON_ONCE(!data_len || !event_data))
> > +		return -EINVAL;
> > +
> > +	down_read(&viommu->veventqs_rwsem);
> > +
> > +	veventq = iommufd_viommu_find_veventq(viommu, type);
> > +	if (!veventq) {
> > +		rc = -EOPNOTSUPP;
> > +		goto out_unlock_veventqs;
> > +	}
> > +
> > +	if (atomic_read(&veventq->num_events) == veventq->depth) {
> > +		vevent = &veventq->overflow;
> > +		goto out_set_header;
> > +	}
> > +
> > +	vevent = kmalloc(struct_size(vevent, event_data, data_len),
> GFP_KERNEL);
> > +	if (!vevent) {
> > +		rc = -ENOMEM;
> > +		goto out_unlock_veventqs;
> 
> This should record an overflow too
> 

In that case probably we want to rename 'overflow' to 'lost_event'
which counts lost events for whatever reasons (overflow, oom, etc.)