diff options
-rw-r--r-- | arch/powerpc/platforms/pseries/iommu.c | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index 33b552ffbe57..4642d6a4d356 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -721,13 +721,13 @@ static int __init disable_ddw_setup(char *str) early_param("disable_ddw", disable_ddw_setup); -static void remove_ddw(struct device_node *np) +static void remove_ddw(struct device_node *np, bool remove_prop) { struct dynamic_dma_window_prop *dwp; struct property *win64; const u32 *ddw_avail; u64 liobn; - int len, ret; + int len, ret = 0; ddw_avail = of_get_property(np, "ibm,ddw-applicable", &len); win64 = of_find_property(np, DIRECT64_PROPNAME, NULL); @@ -761,7 +761,8 @@ static void remove_ddw(struct device_node *np) np->full_name, ret, ddw_avail[2], liobn); delprop: - ret = of_remove_property(np, win64); + if (remove_prop) + ret = of_remove_property(np, win64); if (ret) pr_warning("%s: failed to remove direct window property: %d\n", np->full_name, ret); @@ -805,7 +806,7 @@ static int find_existing_ddw_windows(void) window = kzalloc(sizeof(*window), GFP_KERNEL); if (!window || len < sizeof(struct dynamic_dma_window_prop)) { kfree(window); - remove_ddw(pdn); + remove_ddw(pdn, true); continue; } @@ -1045,7 +1046,7 @@ out_free_window: kfree(window); out_clear_window: - remove_ddw(pdn); + remove_ddw(pdn, true); out_free_prop: kfree(win64->name); @@ -1255,7 +1256,14 @@ static int iommu_reconfig_notifier(struct notifier_block *nb, unsigned long acti switch (action) { case OF_RECONFIG_DETACH_NODE: - remove_ddw(np); + /* + * Removing the property will invoke the reconfig + * notifier again, which causes dead-lock on the + * read-write semaphore of the notifier chain. So + * we have to remove the property when releasing + * the device node. + */ + remove_ddw(np, false); if (pci && pci->iommu_table) iommu_free_table(pci->iommu_table, np->full_name); |