On Tue, Mar 14, 2017 at 07:36:00AM -0400, Prarit Bhargava wrote:
> When booting top-of-tree the following WARN_ON triggers in the kernel on
> a 15h AMD system.
> WARNING: CPU: 2 PID: 621 at drivers/base/dd.c:349 driver_probe_device+0x38c
> Modules linked in: i2c_amd756(+) amd_rng sg pcspkr parport_pc(+) parport k8
> CPU: 2 PID: 621 Comm: systemd-udevd Not tainted 4.11.0-0.rc1.git0.1.el7_UNS
> Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./TYAN High-End
> Call Trace:
> ? driver_probe_device+0x470/0x470
> ? 0xffffffffa0037000
> amd756_driver_init+0x1e/0x1000 [i2c_amd756]
> ? __vunmap+0x85/0xd0
> ? do_init_module+0x27/0x1fa
> ? m_show+0x1c0/0x1c0
> There are PCI devices that contain both a RNG and SMBUS device. The
> RNG device is initialized by the amd-rng driver but the driver does not
> register against the device. The SMBUS device is initialized by the
> i2c-amd756 driver and registers against the device and hits the WARN_ON()
> because the amd-rng driver has already allocated resources against the
> The amd-rng driver was incorrectly migrated to the device resource model
> (devres), and after code inspection I found that the geode-rng driver was also
> incorrectly migrated. These drivers are using devres but do not register a
> driver against the device, and both drivers are expecting a memory cleanup on
> a driver detach that will never happen. This results in a memory leak when
> driver is unloaded and the inability to reload the driver.
> Revert 31b2a73c9c5f ("hwrng: amd - Migrate to managed API"), and 6e9b5e76882c
> ("hwrng: geode - Migrate to managed API").
> Signed-off-by: Prarit Bhargava <pra...@redhat.com>
> Fixes: 31b2a73c9c5f ("hwrng: amd - Migrate to managed API").
> Fixes: 6e9b5e76882c ("hwrng: geode - Migrate to managed API")
> Cc: Matt Mackall <m...@selenic.com>
> Cc: Herbert Xu <herb...@gondor.apana.org.au>
> Cc: Corentin LABBE <clabbe.montj...@gmail.com>
> Cc: PrasannaKumar Muralidharan <prasannatsmku...@gmail.com>
> Cc: Wei Yongjun <weiyongj...@huawei.com>
> Cc: email@example.com
> Cc: linux-ge...@lists.infradead.org
Both patches applied. Thanks.
Email: Herbert Xu <herb...@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt