From 283d245468a2b61c41aa8b582f25ed5615d1c304 Mon Sep 17 00:00:00 2001 From: Vasant Hegde Date: Sun, 17 May 2026 12:29:25 +0000 Subject: [PATCH] iommu/amd: Fix premature break in init_iommu_one() In init_iommu_one(), when processing IOMMU EFR attributes, the code checks whether GASUP is enabled. If GASUP is not enabled, the code falls back to legacy guest IR mode and then breaks out of the switch statement. This break incorrectly skips the subsequent initialization steps that follow the GASUP check. These initializations are independent of GASUP support and must always be performed. Fix this by replacing the early break with a conditional else block, ensuring that the XTSUP check is only skipped when GASUP is not available. Fixes: a44092e326d4 ("iommu/amd: Use IVHD EFR for early initialization of IOMMU features") Reported-by: Sudheer Dantuluri Tested-by: Dheeraj Kumar Srivastava Signed-off-by: Vasant Hegde Signed-off-by: Joerg Roedel --- drivers/iommu/amd/init.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c index 16073b5614b9..a7dfbd515863 100644 --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -1917,12 +1917,11 @@ static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h, /* XT and GAM require GA mode. */ if ((h->efr_reg & (0x1 << IOMMU_EFR_GASUP_SHIFT)) == 0) { amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY; - break; + } else { + if (h->efr_reg & BIT(IOMMU_EFR_XTSUP_SHIFT)) + amd_iommu_xt_mode = IRQ_REMAP_X2APIC_MODE; } - if (h->efr_reg & BIT(IOMMU_EFR_XTSUP_SHIFT)) - amd_iommu_xt_mode = IRQ_REMAP_X2APIC_MODE; - if (h->efr_attr & BIT(IOMMU_IVHD_ATTR_HATDIS_SHIFT)) { pr_warn_once("Host Address Translation is not supported.\n"); amd_iommu_hatdis = true;