From: Amir Shehata <amir.shehata@xxxxxxxxx> There is a use case where lnet can be unloaded while there are no NIs configured. Removing lnet in this case will cause LNetFini() to be called without a prior call to LNetNIFini(). This will cause the LASSERT(the_lnet.ln_refcount == 0) to be triggered. To deal with this use case when LNet is configured a reference count on the module is taken using try_module_get(). This way LNet must be unconfigured before it could be removed; therefore avoiding the above case. When LNet is unconfigured module_put() is called to return the reference count. Signed-off-by: Amir Shehata <amir.shehata@xxxxxxxxx> Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6010 Reviewed-on: http://review.whamcloud.com/13110 Reviewed-by: James Simmons <uja.ornl@xxxxxxxxx> Reviewed-by: Doug Oucharek <doug.s.oucharek@xxxxxxxxx> Reviewed-by: Oleg Drokin <oleg.drokin@xxxxxxxxx> --- drivers/staging/lustre/lnet/lnet/module.c | 9 +++++++++ 1 files changed, 9 insertions(+), 0 deletions(-) diff --git a/drivers/staging/lustre/lnet/lnet/module.c b/drivers/staging/lustre/lnet/lnet/module.c index 48eb085..b1f32a6 100644 --- a/drivers/staging/lustre/lnet/lnet/module.c +++ b/drivers/staging/lustre/lnet/lnet/module.c @@ -53,13 +53,21 @@ lnet_configure(void *arg) mutex_lock(&lnet_config_mutex); if (!the_lnet.ln_niinit_self) { + rc = try_module_get(THIS_MODULE); + + if (rc != 1) + goto out; + rc = LNetNIInit(LNET_PID_LUSTRE); if (rc >= 0) { the_lnet.ln_niinit_self = 1; rc = 0; + } else { + module_put(THIS_MODULE); } } +out: mutex_unlock(&lnet_config_mutex); return rc; } @@ -74,6 +82,7 @@ lnet_unconfigure(void) if (the_lnet.ln_niinit_self) { the_lnet.ln_niinit_self = 0; LNetNIFini(); + module_put(THIS_MODULE); } mutex_lock(&the_lnet.ln_api_mutex); -- 1.7.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
