From: Qian Cai <cai@xxxxxx>
Subject: drivers/iommu/intel-iommu.c: fix variable 'iommu' set but not used
cf04eee8bf0e ("iommu/vt-d: Include ACPI devices in iommu=pt") added
for_each_active_iommu() in iommu_prepare_static_identity_mapping() but
never used the each element, i.e, "drhd->iommu".
drivers/iommu/intel-iommu.c: In function
'iommu_prepare_static_identity_mapping':
drivers/iommu/intel-iommu.c:3037:22: warning: variable 'iommu' set but
not used [-Wunused-but-set-variable]
struct intel_iommu *iommu;
Fixed the warning by appending a compiler attribute __maybe_unused for it.
Link: http://lkml.kernel.org/r/20190523013314.2732-1-cai@xxxxxx
Signed-off-by: Qian Cai <cai@xxxxxx>
Suggested-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Joerg Roedel <jroedel@xxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/iommu/intel-iommu.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/iommu/intel-iommu.c~iommu-intel-fix-variable-iommu-set-but-not-used
+++ a/drivers/iommu/intel-iommu.c
@@ -3034,7 +3034,8 @@ static int __init iommu_prepare_static_i
{
struct pci_dev *pdev = NULL;
struct dmar_drhd_unit *drhd;
- struct intel_iommu *iommu;
+ /* To avoid a -Wunused-but-set-variable warning. */
+ struct intel_iommu *iommu __maybe_unused;
struct device *dev;
int i;
int ret = 0;
_
