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Date: Fri, 15 Aug 2025 15:15:33 +0100
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Subject: Re: [PATCH] iommufd: viommu: free memory allocated by kvcalloc()
 using kvfree()
To: Markus Elfring <Markus.Elfring@web.de>,
 Akhilesh Patil <akhilesh@ee.iitb.ac.in>, iommu@lists.linux.dev
Cc: akhileshpatilvnit@gmail.com, LKML <linux-kernel@vger.kernel.org>,
 Jason Gunthorpe <jgg@nvidia.com>, Jason Gunthorpe <jgg@ziepe.ca>,
 =?UTF-8?B?SsO2cmcgUsO2ZGVs?= <joro@8bytes.org>,
 Kevin Tian <kevin.tian@intel.com>, Lu Baolu <baolu.lu@linux.intel.com>,
 Nicolin Chen <nicolinc@nvidia.com>, Pranjal Shrivastava <praan@google.com>,
 Shuah Khan <skhan@linuxfoundation.org>, Will Deacon <will@kernel.org>
References: <aJifyVV2PL6WGEs6@bhairav-test.ee.iitb.ac.in>
 <712b3b74-cfbd-45d8-8c19-6f2929b71358@web.de>
From: Robin Murphy <robin.murphy@foss.arm.com>
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On 15/08/2025 2:42 pm, Markus Elfring wrote:
>> Use kvfree() instead of kfree() to free pages allocated by kvcalloc()
>> in iommufs_hw_queue_alloc_phys() to fix potential memory corruption.
>> Ensure the memory is properly freed, as kvcalloc may internally use
>> vmalloc or kmalloc depending on available memory in the system.
> 
> Will another bit of background information become helpful
> for an improved change description?

No it will not. Please stop pointlessly nitpicking. A thing that is 
allocated with kv*alloc() must be freed with kvfree(); that alone is all 
that needs to be said to explain and justify any patch fixing this 
particular bug.

Thanks,
Robin.