linux-kernel - [devm_kfree() usage] When should devm

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-next>] [day] [month] [year] [list]

Message-ID: <20190525020305.GA10933@zhanggen-UX430UQ>
Date:   Sat, 25 May 2019 10:03:05 +0800
From:   Gen Zhang <blackgod016574@...il.com>
To:     rafael@...nel.org, gregkh@...uxfoundation.org
Cc:     jonathanh@...dia.com, linux-kernel@...r.kernel.org
Subject: [devm_kfree() usage] When should devm_kfree() be used?

devm_kmalloc() is used to allocate memory for a driver dev. Comments
above the definition and doc 
(https://www.kernel.org/doc/Documentation/driver-model/devres.txt) all
imply that allocated the memory is automatically freed on driver attach,
no matter allocation fail or not. However, I examined the code, and
there are many sites that devm_kfree() is used to free devm_kmalloc().
e.g. hisi_sas_debugfs_init() in drivers/scsi/hisi_sas/hisi_sas_main.c.
So I am totally confused about this issue. Can anybody give me some
guidance? When should we use devm_kfree()?

Thanks
Gen