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| author | Robin Murphy <robin.murphy@arm.com> | 2020-06-02 15:08:18 +0200 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2020-06-30 10:42:27 +0200 |
| commit | d3e3d2be688b4b5864538de61e750721a311e4fc (patch) | |
| tree | 18abb2488bd27e324197efd2e25e13dea0dcefba /drivers/iommu/iova.c | |
| parent | Linux 5.8-rc3 (diff) | |
| download | linux-d3e3d2be688b4b5864538de61e750721a311e4fc.tar.xz linux-d3e3d2be688b4b5864538de61e750721a311e4fc.zip | |
iommu/iova: Don't BUG on invalid PFNs
Unlike the other instances which represent a complete loss of
consistency within the rcache mechanism itself, or a fundamental
and obvious misconfiguration by an IOMMU driver, the BUG_ON() in
iova_magazine_free_pfns() can be provoked at more or less any time
in a "spooky action-at-a-distance" manner by any old device driver
passing nonsense to dma_unmap_*() which then propagates through to
queue_iova().
Not only is this well outside the IOVA layer's control, it's also
nowhere near fatal enough to justify panicking anyway - all that
really achieves is to make debugging the offending driver more
difficult. Let's simply WARN and otherwise ignore bogus PFNs.
Reported-by: Prakash Gupta <guptap@codeaurora.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Prakash Gupta <guptap@codeaurora.org>
Link: https://lore.kernel.org/r/acbd2d092b42738a03a21b417ce64e27f8c91c86.1591103298.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu/iova.c')
| -rw-r--r-- | drivers/iommu/iova.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c index 49fc01f2a28d..45a251da5453 100644 --- a/drivers/iommu/iova.c +++ b/drivers/iommu/iova.c @@ -811,7 +811,9 @@ iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad) for (i = 0 ; i < mag->size; ++i) { struct iova *iova = private_find_iova(iovad, mag->pfns[i]); - BUG_ON(!iova); + if (WARN_ON(!iova)) + continue; + private_free_iova(iovad, iova); } |