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| author | Aaron Campbell <aaron@monkey.org> | 2016-07-02 21:23:24 -0300 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2016-07-04 13:34:52 +0200 |
| commit | 0caa7616a6aca449dd68b58cb29bd491d296c2d5 (patch) | |
| tree | caa80d64be89509628aea83babbc05dc3fcb2539 | |
| parent | a99cde438de0c4c0cecc1d1af1a55a75b10bfdef (diff) | |
| download | linux-xen-0caa7616a6aca449dd68b58cb29bd491d296c2d5.tar.gz | |
iommu/vt-d: Fix infinite loop in free_all_cpu_cached_iovas
Per VT-d spec Section 10.4.2 ("Capability Register"), the maximum
number of possible domains is 64K; indeed this is the maximum value
that the cap_ndoms() macro will expand to. Since the value 65536
will not fix in a u16, the 'did' variable must be promoted to an
int, otherwise the test for < 65536 will always be true and the
loop will never end.
The symptom, in my case, was a hung machine during suspend.
Fixes: 3bd4f9112f87 ("iommu/vt-d: Fix overflow of iommu->domains array")
Signed-off-by: Aaron Campbell <aaron@monkey.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
| -rw-r--r-- | drivers/iommu/intel-iommu.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index cfe410eedaf0b..323dac9900ba3 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -4602,13 +4602,13 @@ static void free_all_cpu_cached_iovas(unsigned int cpu) for (i = 0; i < g_num_of_iommus; i++) { struct intel_iommu *iommu = g_iommus[i]; struct dmar_domain *domain; - u16 did; + int did; if (!iommu) continue; for (did = 0; did < cap_ndoms(iommu->cap); did++) { - domain = get_iommu_domain(iommu, did); + domain = get_iommu_domain(iommu, (u16)did); if (!domain) continue; |