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Signed-off-by: Jinhui Guo --- drivers/iommu/amd/init.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c index ba9e582a8bbe..6e9eab365123 100644 --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -3212,8 +3212,10 @@ static bool __init detect_ivrs(void) } =20 out: - /* Make sure ACS will be enabled during PCI probe */ - pci_request_acs(); + if (!amd_iommu_disabled || amd_iommu_force_enable) { + /* Make sure ACS will be enabled during PCI probe */ + pci_request_acs(); + } =20 return true; } --=20 2.20.1