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Subject[PATCH] pci: Avoid reentrant calls to work_on_cpu
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This change is meant to fix a deadlock seen when pci_enable_sriov was
called from within a driver's probe routine. The issue was that
work_on_cpu calls flush_work which attempts to flush a work queue for a
cpu that we are currently working in. In order to avoid the reentrant
path we just skip the call to work_on_cpu in the case that the device
node matches our current node.

Reported-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
---

This patch is meant to address the issue pointed out in an earlier patch
sent by Yinghai Lu titled:
[PATCH 6/7] PCI: Make sure VF's driver get attached after PF's

drivers/pci/pci-driver.c | 14 +++++++++-----
1 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 79277fb..caeb1c0 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -277,12 +277,16 @@ static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
int error, node;
struct drv_dev_and_id ddi = { drv, dev, id };

- /* Execute driver initialization on node where the device's
- bus is attached to. This way the driver likely allocates
- its local memory on the right node without any need to
- change it. */
+ /*
+ * Execute driver initialization on the node where the device's
+ * bus is attached. This way the driver likely allocates
+ * its local memory on the right node without any need to
+ * change it. If the node is the current node just call
+ * local_pci_probe and avoid the possibility of reentrant
+ * calls to work_on_cpu.
+ */
node = dev_to_node(&dev->dev);
- if (node >= 0) {
+ if ((node >= 0) && (node != numa_node_id())) {
int cpu;

get_online_cpus();


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