linux-kernel - [PATCH] iommu/amd: Fix IOMMU AVIC not properly update the is

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-Id: <1584008319-13594-1-git-send-email-suravee.suthikulpanit@amd.com>
Date:   Thu, 12 Mar 2020 05:18:39 -0500
From:   Suravee Suthikulpanit <suravee.suthikulpanit@....com>
To:     linux-kernel@...r.kernel.org, iommu@...ts.linux-foundation.org
Cc:     joro@...tes.org,
        Suravee Suthikulpanit <suravee.suthikulpanit@....com>
Subject: [PATCH] iommu/amd: Fix IOMMU AVIC not properly update the is_run bit in IRTE

Commit b9c6ff94e43a ("iommu/amd: Re-factor guest virtual APIC
(de-)activation code") accidentally left out the ir_data pointer when
calling modity_irte_ga(), which causes the function amd_iommu_update_ga()
to return prematurely due to struct amd_ir_data.ref is NULL and
the "is_run" bit of IRTE does not get updated properly.

This results in bad I/O performance since IOMMU AVIC always generate GA Log
entry and notify IOMMU driver and KVM when it receives interrupt from the
PCI pass-through device instead of directly inject interrupt to the vCPU.

Fixes by passing ir_data when calling modify_irte_ga() as done previously.

Fixes: b9c6ff94e43a ("iommu/amd: Re-factor guest virtual APIC (de-)activation code")
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@....com>
---
 drivers/iommu/amd_iommu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index aac132b..20cce36 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -3826,7 +3826,7 @@ int amd_iommu_activate_guest_mode(void *data)
 	entry->lo.fields_vapic.ga_tag      = ir_data->ga_tag;
 
 	return modify_irte_ga(ir_data->irq_2_irte.devid,
-			      ir_data->irq_2_irte.index, entry, NULL);
+			      ir_data->irq_2_irte.index, entry, ir_data);
 }
 EXPORT_SYMBOL(amd_iommu_activate_guest_mode);
 
@@ -3852,7 +3852,7 @@ int amd_iommu_deactivate_guest_mode(void *data)
 				APICID_TO_IRTE_DEST_HI(cfg->dest_apicid);
 
 	return modify_irte_ga(ir_data->irq_2_irte.devid,
-			      ir_data->irq_2_irte.index, entry, NULL);
+			      ir_data->irq_2_irte.index, entry, ir_data);
 }
 EXPORT_SYMBOL(amd_iommu_deactivate_guest_mode);
 
-- 
1.8.3.1