misc: pci_endpoint_test: Re-init completion for every test

The irq_raised completion used to detect the end of a test case is
initialized when the test device is probed, but never reinitialized again
before a test case. As a result, the irq_raised completion synchronization
is effective only for the first ioctl test case executed. Any subsequent
call to wait_for_completion() by another ioctl() call will immediately
return, potentially too early, leading to false positive failures.

Fix this by reinitializing the irq_raised completion before starting a new
ioctl() test command.

Link: https://lore.kernel.org/r/[email protected]
Fixes: 2c156ac ("misc: Add host side PCI driver for PCI test function device")
Signed-off-by: Damien Le Moal <[email protected]>
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Manivannan Sadhasivam <[email protected]>
Cc: [email protected]

Author: damien-lemoal

drivers/misc/pci_endpoint_test.c

@@ -729,6 +729,10 @@ static long pci_endpoint_test_ioctl(struct file *file, unsigned int cmd,
 	struct pci_dev *pdev = test->pdev;
 
 	mutex_lock(&test->mutex);
+
+	reinit_completion(&test->irq_raised);
+	test->last_irq = -ENODATA;
+
 	switch (cmd) {
 	case PCITEST_BAR:
 		bar = arg;