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Wysocki" , Tianfei zhang Cc: Dionna Glaze , Sean Christopherson , Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , "David S. Miller" , Michael Roth , Russ Weight If a kernel module registers a firmware upload API ops set, then it's unable to be moved due to effectively a cyclic reference that the module depends on the upload which depends on the module. Instead, only require the try_module_get when an upload is requested to disallow unloading a module only while the upload is in progress. Fixes: 97730bbb242c ("firmware_loader: Add firmware-upload support") CC: Sean Christopherson CC: Paolo Bonzini CC: Thomas Gleixner CC: Ingo Molnar CC: Borislav Petkov CC: Dave Hansen CC: Ashish Kalra CC: Tom Lendacky CC: John Allen CC: Herbert Xu CC: "David S. Miller" CC: Michael Roth CC: Luis Chamberlain CC: Russ Weight CC: Danilo Krummrich CC: Greg Kroah-Hartman CC: "Rafael J. Wysocki" CC: Tianfei zhang Tested-by: Ashish Kalra Signed-off-by: Dionna Glaze Reviewed-by: Russ Weight --- drivers/base/firmware_loader/sysfs_upload.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/drivers/base/firmware_loader/sysfs_upload.c b/drivers/base/firmware_loader/sysfs_upload.c index 829270067d163..7d9c6aef7720a 100644 --- a/drivers/base/firmware_loader/sysfs_upload.c +++ b/drivers/base/firmware_loader/sysfs_upload.c @@ -204,6 +204,7 @@ static void fw_upload_main(struct work_struct *work) fwlp->ops->cleanup(fwl); putdev_exit: + module_put(fwlp->module); put_device(fw_dev->parent); /* @@ -239,6 +240,9 @@ int fw_upload_start(struct fw_sysfs *fw_sysfs) } fwlp = fw_sysfs->fw_upload_priv; + if (!try_module_get(fwlp->module)) /* released in fw_upload_main */ + return -EFAULT; + mutex_lock(&fwlp->lock); /* Do not interfere with an on-going fw_upload */ @@ -310,13 +314,10 @@ firmware_upload_register(struct module *module, struct device *parent, return ERR_PTR(-EINVAL); } - if (!try_module_get(module)) - return ERR_PTR(-EFAULT); - fw_upload = kzalloc(sizeof(*fw_upload), GFP_KERNEL); if (!fw_upload) { ret = -ENOMEM; - goto exit_module_put; + goto exit_err; } fw_upload_priv = kzalloc(sizeof(*fw_upload_priv), GFP_KERNEL); @@ -358,7 +359,7 @@ firmware_upload_register(struct module *module, struct device *parent, if (ret) { dev_err(fw_dev, "%s: device_register failed\n", __func__); put_device(fw_dev); - goto exit_module_put; + goto exit_err; } return fw_upload; @@ -372,8 +373,7 @@ firmware_upload_register(struct module *module, struct device *parent, free_fw_upload: kfree(fw_upload); -exit_module_put: - module_put(module); +exit_err: return ERR_PTR(ret); } @@ -387,7 +387,6 @@ void firmware_upload_unregister(struct fw_upload *fw_upload) { struct fw_sysfs *fw_sysfs = fw_upload->priv; struct fw_upload_priv *fw_upload_priv = fw_sysfs->fw_upload_priv; - struct module *module = fw_upload_priv->module; mutex_lock(&fw_upload_priv->lock); if (fw_upload_priv->progress == FW_UPLOAD_PROG_IDLE) { @@ -403,6 +402,5 @@ void firmware_upload_unregister(struct fw_upload *fw_upload) unregister: device_unregister(&fw_sysfs->dev); - module_put(module); } EXPORT_SYMBOL_GPL(firmware_upload_unregister);