From: Dan Williams <dan.j.williams@intel.com>
Date: Thu, 13 Jun 2019 15:56:24 -0700
Subject: PCI/P2PDMA: fix the gen_pool_add_virt() failure path
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Patch-mainline: v5.2-rc5
Git-commit: e615a191216e3fb4e9c0d239007f2b0cd48f28bf
References: bsc#1103992 FATE#326009
The pci_p2pdma_add_resource() implementation immediately frees the pgmap
if gen_pool_add_virt() fails. However, that means that when @dev
triggers a devres release devm_memremap_pages_release() will crash
trying to access the freed @pgmap.
Use the new devm_memunmap_pages() to manually free the mapping in the
error path.
Link: http://lkml.kernel.org/r/155727337603.292046.13101332703665246702.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Fixes: 52916982af48 ("PCI/P2PDMA: Support peer-to-peer memory")
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/pci/p2pdma.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/pci/p2pdma.c
+++ b/drivers/pci/p2pdma.c
@@ -160,13 +160,15 @@ int pci_p2pdma_add_resource(struct pci_d
error = devm_add_action_or_reset(&pdev->dev, pci_p2pdma_percpu_kill,
&pdev->p2pdma->devmap_ref);
if (error)
- goto pgmap_free;
+ goto pages_free;
pci_info(pdev, "added peer-to-peer DMA memory %pR\n",
&pgmap->res);
return 0;
+pages_free:
+ devm_memunmap_pages(&pdev->dev, pgmap);
pgmap_free:
devm_kfree(&pdev->dev, pgmap);
return error;