diff options
Diffstat (limited to '0008-x86-MCE-AMD-Allow-Reserved-types-to-be-overwritten-i.patch')
| -rw-r--r-- | 0008-x86-MCE-AMD-Allow-Reserved-types-to-be-overwritten-i.patch | 96 |
1 files changed, 0 insertions, 96 deletions
diff --git a/0008-x86-MCE-AMD-Allow-Reserved-types-to-be-overwritten-i.patch b/0008-x86-MCE-AMD-Allow-Reserved-types-to-be-overwritten-i.patch deleted file mode 100644 index 67d5d92c7092..000000000000 --- a/0008-x86-MCE-AMD-Allow-Reserved-types-to-be-overwritten-i.patch +++ /dev/null @@ -1,96 +0,0 @@ -From 14e0c3a2f956421e0731a1b5e474b3428c8bda24 Mon Sep 17 00:00:00 2001 -From: Yazen Ghannam <yazen.ghannam@amd.com> -Date: Thu, 21 Nov 2019 08:15:08 -0600 -Subject: [PATCH 08/20] x86/MCE/AMD: Allow Reserved types to be overwritten in - smca_banks[] - -Each logical CPU in Scalable MCA systems controls a unique set of MCA -banks in the system. These banks are not shared between CPUs. The bank -types and ordering will be the same across CPUs on currently available -systems. - -However, some CPUs may see a bank as Reserved/Read-as-Zero (RAZ) while -other CPUs do not. In this case, the bank seen as Reserved on one CPU is -assumed to be the same type as the bank seen as a known type on another -CPU. - -In general, this occurs when the hardware represented by the MCA bank -is disabled, e.g. disabled memory controllers on certain models, etc. -The MCA bank is disabled in the hardware, so there is no possibility of -getting an MCA/MCE from it even if it is assumed to have a known type. - -For example: - -Full system: - Bank | Type seen on CPU0 | Type seen on CPU1 - ------------------------------------------------ - 0 | LS | LS - 1 | UMC | UMC - 2 | CS | CS - -System with hardware disabled: - Bank | Type seen on CPU0 | Type seen on CPU1 - ------------------------------------------------ - 0 | LS | LS - 1 | UMC | RAZ - 2 | CS | CS - -For this reason, there is a single, global struct smca_banks[] that is -initialized at boot time. This array is initialized on each CPU as it -comes online. However, the array will not be updated if an entry already -exists. - -This works as expected when the first CPU (usually CPU0) has all -possible MCA banks enabled. But if the first CPU has a subset, then it -will save a "Reserved" type in smca_banks[]. Successive CPUs will then -not be able to update smca_banks[] even if they encounter a known bank -type. - -This may result in unexpected behavior. Depending on the system -configuration, a user may observe issues enumerating the MCA -thresholding sysfs interface. The issues may be as trivial as sysfs -entries not being available, or as severe as system hangs. - -For example: - - Bank | Type seen on CPU0 | Type seen on CPU1 - ------------------------------------------------ - 0 | LS | LS - 1 | RAZ | UMC - 2 | CS | CS - -Extend the smca_banks[] entry check to return if the entry is a -non-reserved type. Otherwise, continue so that CPUs that encounter a -known bank type can update smca_banks[]. - -Fixes: 68627a697c19 ("x86/mce/AMD, EDAC/mce_amd: Enumerate Reserved SMCA bank type") -Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> -Signed-off-by: Borislav Petkov <bp@suse.de> -Cc: "H. Peter Anvin" <hpa@zytor.com> -Cc: Ingo Molnar <mingo@kernel.org> -Cc: linux-edac <linux-edac@vger.kernel.org> -Cc: <stable@vger.kernel.org> -Cc: Thomas Gleixner <tglx@linutronix.de> -Cc: Tony Luck <tony.luck@intel.com> -Cc: x86-ml <x86@kernel.org> -Link: https://lkml.kernel.org/r/20191121141508.141273-1-Yazen.Ghannam@amd.com ---- - arch/x86/kernel/cpu/mce/amd.c | 2 +- - 1 file changed, 1 insertion(+), 1 deletion(-) - -diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c -index c7ab0d38af79..259f3f4e2e5f 100644 ---- a/arch/x86/kernel/cpu/mce/amd.c -+++ b/arch/x86/kernel/cpu/mce/amd.c -@@ -266,7 +266,7 @@ static void smca_configure(unsigned int bank, unsigned int cpu) - smca_set_misc_banks_map(bank, cpu); - - /* Return early if this bank was already initialized. */ -- if (smca_banks[bank].hwid) -+ if (smca_banks[bank].hwid && smca_banks[bank].hwid->hwid_mcatype != 0) - return; - - if (rdmsr_safe(MSR_AMD64_SMCA_MCx_IPID(bank), &low, &high)) { --- -2.24.1 - |