Re: [PATCH] EDAC/Intel: Do not load EDAC driver when running as a guest

From: Luck, Tony
Date: Tue Jun 15 2021 - 12:45:29 EST


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.

Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
---
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 238a4ad1e526..fa08622ff2a8 100644
--- a/drivers/edac/i10nm_base.c
+++ b/drivers/edac/i10nm_base.c
@@ -278,6 +278,9 @@ static int __init i10nm_init(void)
if (owner && strncmp(owner, EDAC_MOD_STR, sizeof(EDAC_MOD_STR)))
return -EBUSY;

+ if (boot_cpu_has(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 928f63a374c7..5c7b36e2325f 100644
--- a/drivers/edac/pnd2_edac.c
+++ b/drivers/edac/pnd2_edac.c
@@ -1554,6 +1554,9 @@ static int __init pnd2_init(void)
if (owner && strncmp(owner, EDAC_MOD_STR, sizeof(EDAC_MOD_STR)))
return -EBUSY;

+ if (boot_cpu_has(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 93daa4297f2e..7d3b2b164e3c 100644
--- a/drivers/edac/sb_edac.c
+++ b/drivers/edac/sb_edac.c
@@ -3510,6 +3510,9 @@ static int __init sbridge_init(void)
if (owner && strncmp(owner, EDAC_MOD_STR, sizeof(EDAC_MOD_STR)))
return -EBUSY;

+ if (boot_cpu_has(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 6a4f0b27c654..c2f9da941217 100644
--- a/drivers/edac/skx_base.c
+++ b/drivers/edac/skx_base.c
@@ -656,6 +656,9 @@ static int __init skx_init(void)
if (owner && strncmp(owner, EDAC_MOD_STR, sizeof(EDAC_MOD_STR)))
return -EBUSY;

+ if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
+ return -ENODEV;
+
id = x86_match_cpu(skx_cpuids);
if (!id)
return -ENODEV;
--
2.29.2