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@@ -1,86 +0,0 @@
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-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
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-From: Yazen Ghannam <[email protected]>
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-Date: Thu, 21 Nov 2019 08:15:08 -0600
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-Subject: [PATCH] x86/MCE/AMD: Allow Reserved types to be overwritten in
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- smca_banks[]
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-
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-Each logical CPU in Scalable MCA systems controls a unique set of MCA
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-banks in the system. These banks are not shared between CPUs. The bank
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-types and ordering will be the same across CPUs on currently available
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-systems.
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-
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-However, some CPUs may see a bank as Reserved/Read-as-Zero (RAZ) while
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-other CPUs do not. In this case, the bank seen as Reserved on one CPU is
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-assumed to be the same type as the bank seen as a known type on another
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-CPU.
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-
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-In general, this occurs when the hardware represented by the MCA bank
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-is disabled, e.g. disabled memory controllers on certain models, etc.
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-The MCA bank is disabled in the hardware, so there is no possibility of
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-getting an MCA/MCE from it even if it is assumed to have a known type.
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-
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-For example:
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-
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-Full system:
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- Bank | Type seen on CPU0 | Type seen on CPU1
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- ------------------------------------------------
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- 0 | LS | LS
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- 1 | UMC | UMC
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- 2 | CS | CS
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-
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-System with hardware disabled:
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- Bank | Type seen on CPU0 | Type seen on CPU1
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- ------------------------------------------------
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- 0 | LS | LS
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- 1 | UMC | RAZ
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- 2 | CS | CS
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-
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-For this reason, there is a single, global struct smca_banks[] that is
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-initialized at boot time. This array is initialized on each CPU as it
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-comes online. However, the array will not be updated if an entry already
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-exists.
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-
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-This works as expected when the first CPU (usually CPU0) has all
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-possible MCA banks enabled. But if the first CPU has a subset, then it
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-will save a "Reserved" type in smca_banks[]. Successive CPUs will then
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-not be able to update smca_banks[] even if they encounter a known bank
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-type.
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-
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-This may result in unexpected behavior. Depending on the system
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-configuration, a user may observe issues enumerating the MCA
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-thresholding sysfs interface. The issues may be as trivial as sysfs
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-entries not being available, or as severe as system hangs.
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-
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-For example:
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-
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- Bank | Type seen on CPU0 | Type seen on CPU1
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- ------------------------------------------------
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- 0 | LS | LS
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- 1 | RAZ | UMC
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- 2 | CS | CS
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-
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-Extend the smca_banks[] entry check to return if the entry is a
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-non-reserved type. Otherwise, continue so that CPUs that encounter a
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-known bank type can update smca_banks[].
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-
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-Fixes: 68627a697c19 ("x86/mce/AMD, EDAC/mce_amd: Enumerate Reserved SMCA bank type")
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-Signed-off-by: Yazen Ghannam <[email protected]>
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-Signed-off-by: Borislav Petkov <[email protected]>
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-Signed-off-by: Thomas Lamprecht <[email protected]>
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----
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- arch/x86/kernel/cpu/mce/amd.c | 2 +-
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- 1 file changed, 1 insertion(+), 1 deletion(-)
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-
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-diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c
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-index 6ea7fdc82f3c..08e09c8c269f 100644
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---- a/arch/x86/kernel/cpu/mce/amd.c
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-+++ b/arch/x86/kernel/cpu/mce/amd.c
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-@@ -266,7 +266,7 @@ static void smca_configure(unsigned int bank, unsigned int cpu)
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- smca_set_misc_banks_map(bank, cpu);
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-
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- /* Return early if this bank was already initialized. */
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-- if (smca_banks[bank].hwid)
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-+ if (smca_banks[bank].hwid && smca_banks[bank].hwid->hwid_mcatype != 0)
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- return;
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-
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- if (rdmsr_safe_on_cpu(cpu, MSR_AMD64_SMCA_MCx_IPID(bank), &low, &high)) {
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Thomas Lamprecht