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Date: Fri, 12 Jan 2024 17:31:10 +0200
From: Ido Schimmel <idosch@idosch.org>
To: Catalin Marinas <catalin.marinas@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>, joro@8bytes.org, will@kernel.org,
	iommu@lists.linux.dev, linux-kernel@vger.kernel.org,
	zhangzekun11@huawei.com, john.g.garry@oracle.com,
	dheerajkumar.srivastava@amd.com, jsnitsel@redhat.com
Subject: Re: [PATCH v3 0/2] iommu/iova: Make the rcache depot properly
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On Thu, Jan 11, 2024 at 10:13:01AM +0000, Catalin Marinas wrote:
> On Thu, Jan 11, 2024 at 10:20:27AM +0200, Ido Schimmel wrote:
> > On Wed, Jan 10, 2024 at 05:58:15PM +0000, Catalin Marinas wrote:
> > > Transient false positives are possible, especially as the code doesn't
> > > use a double-linked list (for the latter, kmemleak does checksumming and
> > > detects the prev/next change, defers the reporting until the object
> > > becomes stable). That said, if a new scan is forced (echo scan >
> > > /sys/kernel/debug/kmemleak), are the same objects still listed as leaks?
> > > If yes, they may not be transient.
> > 
> > We are doing "scan" and "clear" after each test. I will disable the
> > "clear" and see if the leaks persist.
> 
> If it is indeed a false positive

Looks like the leaks are transient. After removing the "clear" step the
leaks do not seem to persist.

> you can try the patch below (I haven't given it any run-time test,
> only compiled):

Will try and let you know next week.

Thanks