[PATCH AUTOSEL 5.4 17/26] EDAC/Intel: Do not load EDAC driver when running as a guest

[Sasha Levin]

From: "Luck, Tony" <tony.luck@xxxxxxxxx>

[ Upstream commit f0a029fff4a50eb01648810a77ba1873e829fdd4 ]

There's little to no point in loading an EDAC driver running in a guest:
1) The CPU model reported by CPUID may not represent actual h/w
2) The hypervisor likely does not pass in access to memory controller devices
3) Hypervisors generally do not pass corrected error details to guests

Add a check in each of the Intel EDAC drivers for X86_FEATURE_HYPERVISOR
and simply return -ENODEV in the init routine.

Acked-by: Borislav Petkov <bp@xxxxxxx>
Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
Link: https://lore.kernel.org/r/20210615174419.GA1087688@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/edac/i10nm_base.c | 3 +++
 drivers/edac/pnd2_edac.c  | 3 +++
 drivers/edac/sb_edac.c    | 3 +++
 drivers/edac/skx_base.c   | 3 +++
 4 files changed, 12 insertions(+)

diff --git a/drivers/edac/i10nm_base.c b/drivers/edac/i10nm_base.c
index dfcde7ed9500..f72be5f94e6f 100644
--- a/drivers/edac/i10nm_base.c
+++ b/drivers/edac/i10nm_base.c
@@ -249,6 +249,9 @@ static int __init i10nm_init(void)
 	if (owner && strncmp(owner, EDAC_MOD_STR, sizeof(EDAC_MOD_STR)))
 		return -EBUSY;
 
+	if (cpu_feature_enabled(X86_FEATURE_HYPERVISOR))
+		return -ENODEV;
+
 	id = x86_match_cpu(i10nm_cpuids);
 	if (!id)
 		return -ENODEV;
diff --git a/drivers/edac/pnd2_edac.c b/drivers/edac/pnd2_edac.c
index dac45e2071b3..e054eb038903 100644
--- a/drivers/edac/pnd2_edac.c
+++ b/drivers/edac/pnd2_edac.c
@@ -1555,6 +1555,9 @@ static int __init pnd2_init(void)
 	if (owner && strncmp(owner, EDAC_MOD_STR, sizeof(EDAC_MOD_STR)))
 		return -EBUSY;
 
+	if (cpu_feature_enabled(X86_FEATURE_HYPERVISOR))
+		return -ENODEV;
+
 	id = x86_match_cpu(pnd2_cpuids);
 	if (!id)
 		return -ENODEV;
diff --git a/drivers/edac/sb_edac.c b/drivers/edac/sb_edac.c
index b557a53c75c4..d39f5bfb8bd9 100644
--- a/drivers/edac/sb_edac.c
+++ b/drivers/edac/sb_edac.c
@@ -3512,6 +3512,9 @@ static int __init sbridge_init(void)
 	if (owner && strncmp(owner, EDAC_MOD_STR, sizeof(EDAC_MOD_STR)))
 		return -EBUSY;
 
+	if (cpu_feature_enabled(X86_FEATURE_HYPERVISOR))
+		return -ENODEV;
+
 	id = x86_match_cpu(sbridge_cpuids);
 	if (!id)
 		return -ENODEV;
diff --git a/drivers/edac/skx_base.c b/drivers/edac/skx_base.c
index 77cd370bd62f..b1d717cb8df9 100644
--- a/drivers/edac/skx_base.c
+++ b/drivers/edac/skx_base.c
@@ -605,6 +605,9 @@ static int __init skx_init(void)
 	if (owner && strncmp(owner, EDAC_MOD_STR, sizeof(EDAC_MOD_STR)))
 		return -EBUSY;
 
+	if (cpu_feature_enabled(X86_FEATURE_HYPERVISOR))
+		return -ENODEV;
+
 	id = x86_match_cpu(skx_cpuids);
 	if (!id)
 		return -ENODEV;
-- 
2.30.2