From 4e55a4c296d3a93c95320cdac0b8e72f3cfefb98 Mon Sep 17 00:00:00 2001 From: Bharat Bhushan Date: Wed, 22 Jun 2016 16:40:48 -0500 Subject: [PATCH 185/226] staging: fsl-mc: fix asymmetry in destroy of mc_io An mc_io represents a mapped MC portal. Previously, an mc_io was created for the root dprc in fsl_mc_bus_probe() and for child dprcs in dprc_probe(). But the free of that data structure happened in the general bus remove callback. This asymmetry resulted in some bugs due to unwanted destroys of mc_io object in some scenarios (e.g. vfio). Fix this bug by making things symmetric-- mc_io created in fsl_mc_bus_probe() is freed in fsl_mc_bus_remove(). The mc_io created in dprc_probe() is freed in dprc_remove(). Signed-off-by: Bharat Bhushan [Stuart: added check for root dprc and reworded commit message] Signed-off-by: Stuart Yoder Signed-off-by: Greg Kroah-Hartman --- drivers/staging/fsl-mc/bus/dprc-driver.c | 5 +++++ drivers/staging/fsl-mc/bus/mc-bus.c | 8 ++++---- 2 files changed, 9 insertions(+), 4 deletions(-) --- a/drivers/staging/fsl-mc/bus/dprc-driver.c +++ b/drivers/staging/fsl-mc/bus/dprc-driver.c @@ -801,6 +801,11 @@ static int dprc_remove(struct fsl_mc_dev dev_set_msi_domain(&mc_dev->dev, NULL); } + if (!fsl_mc_is_root_dprc(&mc_dev->dev)) { + fsl_destroy_mc_io(mc_dev->mc_io); + mc_dev->mc_io = NULL; + } + dev_info(&mc_dev->dev, "DPRC device unbound from driver"); return 0; } --- a/drivers/staging/fsl-mc/bus/mc-bus.c +++ b/drivers/staging/fsl-mc/bus/mc-bus.c @@ -579,10 +579,6 @@ void fsl_mc_device_remove(struct fsl_mc_ if (strcmp(mc_dev->obj_desc.type, "dprc") == 0) { mc_bus = to_fsl_mc_bus(mc_dev); - if (mc_dev->mc_io) { - fsl_destroy_mc_io(mc_dev->mc_io); - mc_dev->mc_io = NULL; - } if (fsl_mc_is_root_dprc(&mc_dev->dev)) { if (atomic_read(&root_dprc_count) > 0) @@ -810,6 +806,10 @@ static int fsl_mc_bus_remove(struct plat return -EINVAL; fsl_mc_device_remove(mc->root_mc_bus_dev); + + fsl_destroy_mc_io(mc->root_mc_bus_dev->mc_io); + mc->root_mc_bus_dev->mc_io = NULL; + dev_info(&pdev->dev, "Root MC bus device removed"); return 0; }