[PATCH] dma-debug: remove broken dma memory leak detection for 2.6.30

From: Joerg Roedel
Date: Fri Apr 24 2009 - 08:36:21 EST


The feature needs some more work because the notfier which is used to
check for pending allocations is called before the device drivers
->remove() function. Therefore this feature reports false positives. A
real fix for this issue is to introduce a new notifier event which sent
_after_ the driver has deinitialized itself. That will done for the next
kernel version.

Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx>
---
lib/dma-debug.c | 53 +----------------------------------------------------
1 files changed, 1 insertions(+), 52 deletions(-)

diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index d3da7ed..69da09a 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -400,60 +400,9 @@ out_err:
return -ENOMEM;
}

-static int device_dma_allocations(struct device *dev)
-{
- struct dma_debug_entry *entry;
- unsigned long flags;
- int count = 0, i;
-
- for (i = 0; i < HASH_SIZE; ++i) {
- spin_lock_irqsave(&dma_entry_hash[i].lock, flags);
- list_for_each_entry(entry, &dma_entry_hash[i].list, list) {
- if (entry->dev == dev)
- count += 1;
- }
- spin_unlock_irqrestore(&dma_entry_hash[i].lock, flags);
- }
-
- return count;
-}
-
-static int dma_debug_device_change(struct notifier_block *nb,
- unsigned long action, void *data)
-{
- struct device *dev = data;
- int count;
-
-
- switch (action) {
- case BUS_NOTIFY_UNBIND_DRIVER:
- count = device_dma_allocations(dev);
- if (count == 0)
- break;
- err_printk(dev, NULL, "DMA-API: device driver has pending "
- "DMA allocations while released from device "
- "[count=%d]\n", count);
- break;
- default:
- break;
- }
-
- return 0;
-}
-
void dma_debug_add_bus(struct bus_type *bus)
{
- struct notifier_block *nb;
-
- nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
- if (nb == NULL) {
- printk(KERN_ERR "dma_debug_add_bus: out of memory\n");
- return;
- }
-
- nb->notifier_call = dma_debug_device_change;
-
- bus_register_notifier(bus, nb);
+ /* FIXME: register notifier */
}

/*
--
1.6.2.3


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