cxgb4: fix BUG() on interrupt deallocating path of ULD
Since the introduction of ULD (Upper-Layer Drivers), the MSI-X
deallocating path changed in cxgb4: the driver frees the interrupts
of ULD when unregistering it or on shutdown PCI handler.
Problem is that if a MSI-X is not freed before deallocated in the PCI
layer, it will trigger a BUG() due to still "alive" interrupt being
tentatively quiesced.
The below trace was observed when doing a simple unbind of Chelsio's
adapter PCI function, like:
"echo 001e:80:00.4 > /sys/bus/pci/drivers/cxgb4/unbind"
Trace:
kernel BUG at drivers/pci/msi.c:352!
Oops: Exception in kernel mode, sig: 5 [#1]
...
NIP [c0000000005a5e60] free_msi_irqs+0xa0/0x250
LR [c0000000005a5e50] free_msi_irqs+0x90/0x250
Call Trace:
[c0000000005a5e50] free_msi_irqs+0x90/0x250 (unreliable)
[c0000000005a72c4] pci_disable_msix+0x124/0x180
[d000000011e06708] disable_msi+0x88/0xb0 [cxgb4]
[d000000011e06948] free_some_resources+0xa8/0x160 [cxgb4]
[d000000011e06d60] remove_one+0x170/0x3c0 [cxgb4]
[c00000000058a910] pci_device_remove+0x70/0x110
[c00000000064ef04] device_release_driver_internal+0x1f4/0x2c0
...
This patch fixes the issue by refactoring the shutdown path of ULD on
cxgb4 driver, by properly freeing and disabling interrupts on PCI
remove handler too.
Fixes: 0fbc81b3ad51 ("Allocate resources dynamically for all cxgb4 ULD's")
Reported-by: Harsha Thyagaraja <hathyaga@in.ibm.com>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c
index ec53fe9..71a315b 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c
@@ -589,22 +589,37 @@ void t4_uld_mem_free(struct adapter *adap)
kfree(adap->uld);
}
+/* This function should be called with uld_mutex taken. */
+static void cxgb4_shutdown_uld_adapter(struct adapter *adap, enum cxgb4_uld type)
+{
+ if (adap->uld[type].handle) {
+ adap->uld[type].handle = NULL;
+ adap->uld[type].add = NULL;
+ release_sge_txq_uld(adap, type);
+
+ if (adap->flags & FULL_INIT_DONE)
+ quiesce_rx_uld(adap, type);
+
+ if (adap->flags & USING_MSIX)
+ free_msix_queue_irqs_uld(adap, type);
+
+ free_sge_queues_uld(adap, type);
+ free_queues_uld(adap, type);
+ }
+}
+
void t4_uld_clean_up(struct adapter *adap)
{
unsigned int i;
- if (!adap->uld)
- return;
+ mutex_lock(&uld_mutex);
for (i = 0; i < CXGB4_ULD_MAX; i++) {
if (!adap->uld[i].handle)
continue;
- if (adap->flags & FULL_INIT_DONE)
- quiesce_rx_uld(adap, i);
- if (adap->flags & USING_MSIX)
- free_msix_queue_irqs_uld(adap, i);
- free_sge_queues_uld(adap, i);
- free_queues_uld(adap, i);
+
+ cxgb4_shutdown_uld_adapter(adap, i);
}
+ mutex_unlock(&uld_mutex);
}
static void uld_init(struct adapter *adap, struct cxgb4_lld_info *lld)
@@ -783,15 +798,8 @@ int cxgb4_unregister_uld(enum cxgb4_uld type)
continue;
if (type == CXGB4_ULD_ISCSIT && is_t4(adap->params.chip))
continue;
- adap->uld[type].handle = NULL;
- adap->uld[type].add = NULL;
- release_sge_txq_uld(adap, type);
- if (adap->flags & FULL_INIT_DONE)
- quiesce_rx_uld(adap, type);
- if (adap->flags & USING_MSIX)
- free_msix_queue_irqs_uld(adap, type);
- free_sge_queues_uld(adap, type);
- free_queues_uld(adap, type);
+
+ cxgb4_shutdown_uld_adapter(adap, type);
}
mutex_unlock(&uld_mutex);