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author | Prarit Bhargava <prarit@redhat.com> | 2017-03-14 11:36:01 (GMT) |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-03-30 07:41:26 (GMT) |
commit | 5d6f7b36111d05e1be5ee4de4247ffb56d50dd89 (patch) | |
tree | 007029ad7b835704da05651755457c5a27f34c1b /drivers | |
parent | 0d69a8804134b22432e158a7760afe43d4a4f054 (diff) | |
download | linux-5d6f7b36111d05e1be5ee4de4247ffb56d50dd89.tar.xz |
hwrng: amd - Revert managed API changes
commit 69db7009318758769d625b023402161c750f7876 upstream.
After commit 31b2a73c9c5f ("hwrng: amd - Migrate to managed API"), the
amd-rng driver uses devres with pci_dev->dev to keep track of resources,
but does not actually register a PCI driver. This results in the
following issues:
1. The message
WARNING: CPU: 2 PID: 621 at drivers/base/dd.c:349 driver_probe_device+0x38c
is output when the i2c_amd756 driver loads and attempts to register a PCI
driver. The PCI & device subsystems assume that no resources have been
registered for the device, and the WARN_ON() triggers since amd-rng has
already do so.
2. The driver leaks memory because the driver does not attach to a
device. The driver only uses the PCI device as a reference. devm_*()
functions will release resources on driver detach, which the amd-rng
driver will never do. As a result,
3. The driver cannot be reloaded because there is always a use of the
ioport and region after the first load of the driver.
Revert the changes made by 31b2a73c9c5f ("hwrng: amd - Migrate to managed
API").
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Fixes: 31b2a73c9c5f ("hwrng: amd - Migrate to managed API").
Cc: Matt Mackall <mpm@selenic.com>
Cc: Corentin LABBE <clabbe.montjoie@gmail.com>
Cc: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
Cc: Wei Yongjun <weiyongjun1@huawei.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-geode@lists.infradead.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/char/hw_random/amd-rng.c | 42 |
1 files changed, 34 insertions, 8 deletions
diff --git a/drivers/char/hw_random/amd-rng.c b/drivers/char/hw_random/amd-rng.c index 4a99ac7..9959c76 100644 --- a/drivers/char/hw_random/amd-rng.c +++ b/drivers/char/hw_random/amd-rng.c @@ -55,6 +55,7 @@ MODULE_DEVICE_TABLE(pci, pci_tbl); struct amd768_priv { void __iomem *iobase; struct pci_dev *pcidev; + u32 pmbase; }; static int amd_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait) @@ -148,33 +149,58 @@ found: if (pmbase == 0) return -EIO; - priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + priv = kzalloc(sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; - if (!devm_request_region(&pdev->dev, pmbase + PMBASE_OFFSET, - PMBASE_SIZE, DRV_NAME)) { + if (!request_region(pmbase + PMBASE_OFFSET, PMBASE_SIZE, DRV_NAME)) { dev_err(&pdev->dev, DRV_NAME " region 0x%x already in use!\n", pmbase + 0xF0); - return -EBUSY; + err = -EBUSY; + goto out; } - priv->iobase = devm_ioport_map(&pdev->dev, pmbase + PMBASE_OFFSET, - PMBASE_SIZE); + priv->iobase = ioport_map(pmbase + PMBASE_OFFSET, PMBASE_SIZE); if (!priv->iobase) { pr_err(DRV_NAME "Cannot map ioport\n"); - return -ENOMEM; + err = -EINVAL; + goto err_iomap; } amd_rng.priv = (unsigned long)priv; + priv->pmbase = pmbase; priv->pcidev = pdev; pr_info(DRV_NAME " detected\n"); - return devm_hwrng_register(&pdev->dev, &amd_rng); + err = hwrng_register(&amd_rng); + if (err) { + pr_err(DRV_NAME " registering failed (%d)\n", err); + goto err_hwrng; + } + return 0; + +err_hwrng: + ioport_unmap(priv->iobase); +err_iomap: + release_region(pmbase + PMBASE_OFFSET, PMBASE_SIZE); +out: + kfree(priv); + return err; } static void __exit mod_exit(void) { + struct amd768_priv *priv; + + priv = (struct amd768_priv *)amd_rng.priv; + + hwrng_unregister(&amd_rng); + + ioport_unmap(priv->iobase); + + release_region(priv->pmbase + PMBASE_OFFSET, PMBASE_SIZE); + + kfree(priv); } module_init(mod_init); |