Commit 61ea482b authored Apr 13, 2017 by Dan Williams Committed by Greg Kroah-Hartman Mar 24, 2018

tools/testing/nvdimm: fix nfit_test shutdown crash




[ Upstream commit 8b06b884cd98f7ec8b5028680b99fabfb7b3e192 ]

Keep the nfit_test instances alive until after nfit_test_teardown(), as
we may be doing resource lookups until the final un-registrations have
completed. This fixes crashes of the form.

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
 IP: __release_resource+0x12/0x90
 Call Trace:
  remove_resource+0x23/0x40
  __wrap_remove_resource+0x29/0x30 [nfit_test_iomap]
  acpi_nfit_remove_resource+0xe/0x10 [nfit]
  devm_action_release+0xf/0x20
  release_nodes+0x16d/0x2b0
  devres_release_all+0x3c/0x60
  device_release+0x21/0x90
  kobject_release+0x6a/0x170
  kobject_put+0x2f/0x60
  put_device+0x17/0x20
  platform_device_unregister+0x20/0x30
  nfit_test_exit+0x36/0x960 [nfit_test]

Reported-by: Linda Knippers <linda.knippers@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 92bfedfa

tools/testing/nvdimm/test/nfit.c

+9 −1

Original line number	Diff line number	Diff line
		@@ -1908,6 +1908,7 @@ static __init int nfit_test_init(void)
		put_device(&pdev->dev);
		goto err_register;
		}
		get_device(&pdev->dev);

		rc = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
		if (rc)
		@@ -1926,6 +1927,10 @@ static __init int nfit_test_init(void)
		if (instances[i])
		platform_device_unregister(&instances[i]->pdev);
		nfit_test_teardown();
		for (i = 0; i < NUM_NFITS; i++)
		if (instances[i])
		put_device(&instances[i]->pdev.dev);

		return rc;
		}

		@@ -1933,10 +1938,13 @@ static __exit void nfit_test_exit(void)
		{
		int i;

		platform_driver_unregister(&nfit_test_driver);
		for (i = 0; i < NUM_NFITS; i++)
		platform_device_unregister(&instances[i]->pdev);
		platform_driver_unregister(&nfit_test_driver);
		nfit_test_teardown();

		for (i = 0; i < NUM_NFITS; i++)
		put_device(&instances[i]->pdev.dev);
		class_destroy(nfit_test_dimm);
		}