This is a note to let you know that I've just added the patch titled

EDAC, sb_edac: Don't create a second memory controller if HA1 is not present

to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: edac-sb_edac-don-t-create-a-second-memory-controller-if-ha1-is-not-present.patch and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 15cc3ae001873845b5d842e212478a6570c7d938 Mon Sep 17 00:00:00 2001

From: Qiuxu Zhuo qiuxu.zhuo@intel.com Date: Wed, 13 Sep 2017 18:42:14 +0800 Subject: EDAC, sb_edac: Don't create a second memory controller if HA1 is not present

From: Qiuxu Zhuo qiuxu.zhuo@intel.com

commit 15cc3ae001873845b5d842e212478a6570c7d938 upstream.

Yi Zhang reported the following failure on a 2-socket Haswell (E5-2603v3) server (DELL PowerEdge 730xd):

EDAC sbridge: Some needed devices are missing EDAC MC: Removed device 0 for sb_edac.c Haswell SrcID#0_Ha#0: DEV 0000:7f:12.0 EDAC MC: Removed device 1 for sb_edac.c Haswell SrcID#1_Ha#0: DEV 0000:ff:12.0 EDAC sbridge: Couldn't find mci handler EDAC sbridge: Couldn't find mci handler EDAC sbridge: Failed to register device with error -19.

The refactored sb_edac driver creates the IMC1 (the 2nd memory controller) if any IMC1 device is present. In this case only HA1_TA of IMC1 was present, but the driver expected to find HA1/HA1_TM/HA1_TAD[0-3] devices too, leading to the above failure.

The document [1] says the 'E5-2603 v3' CPU has 4 memory channels max. Yi Zhang inserted one DIMM per channel for each CPU, and did random error address injection test with this patch:

4024 addresses fell in TOLM hole area 12715 addresses fell in CPU_SrcID#0_Ha#0_Chan#0_DIMM#0 12774 addresses fell in CPU_SrcID#0_Ha#0_Chan#1_DIMM#0 12798 addresses fell in CPU_SrcID#0_Ha#0_Chan#2_DIMM#0 12913 addresses fell in CPU_SrcID#0_Ha#0_Chan#3_DIMM#0 12674 addresses fell in CPU_SrcID#1_Ha#0_Chan#0_DIMM#0 12686 addresses fell in CPU_SrcID#1_Ha#0_Chan#1_DIMM#0 12882 addresses fell in CPU_SrcID#1_Ha#0_Chan#2_DIMM#0 12934 addresses fell in CPU_SrcID#1_Ha#0_Chan#3_DIMM#0 106400 addresses were injected totally.

The test result shows that all the 4 channels belong to IMC0 per CPU, so the server really only has one IMC per CPU.

In the 1st page of chapter 2 in datasheet [2], it also says 'E5-2600 v3' implements either one or two IMCs. For CPUs with one IMC, IMC1 is not used and should be ignored.

Thus, do not create a second memory controller if the key HA1 is absent.

[1] http://ark.intel.com/products/83349/Intel-Xeon-Processor-E5-2603-v3-15M-Cach... [2] https://www.intel.com/content/dam/www/public/us/en/documents/datasheets/xeon...

Reported-and-tested-by: Yi Zhang yizhan@redhat.com Signed-off-by: Qiuxu Zhuo qiuxu.zhuo@intel.com Cc: Tony Luck tony.luck@intel.com Cc: linux-edac linux-edac@vger.kernel.org Link: http://lkml.kernel.org/r/20170913104214.7325-1-qiuxu.zhuo@intel.com [ Massage commit message. ] Signed-off-by: Borislav Petkov bp@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/edac/sb_edac.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)

--- a/drivers/edac/sb_edac.c +++ b/drivers/edac/sb_edac.c @@ -462,6 +462,7 @@ static const struct pci_id_table pci_dev static const struct pci_id_descr pci_dev_descr_ibridge[] = { /* Processor Home Agent */ { PCI_DESCR(PCI_DEVICE_ID_INTEL_IBRIDGE_IMC_HA0, 0, IMC0) }, + { PCI_DESCR(PCI_DEVICE_ID_INTEL_IBRIDGE_IMC_HA1, 1, IMC1) },

/* Memory controller */ { PCI_DESCR(PCI_DEVICE_ID_INTEL_IBRIDGE_IMC_HA0_TA, 0, IMC0) }, @@ -472,7 +473,6 @@ static const struct pci_id_descr pci_dev { PCI_DESCR(PCI_DEVICE_ID_INTEL_IBRIDGE_IMC_HA0_TAD3, 0, IMC0) },

/* Optional, mode 2HA */ - { PCI_DESCR(PCI_DEVICE_ID_INTEL_IBRIDGE_IMC_HA1, 1, IMC1) }, { PCI_DESCR(PCI_DEVICE_ID_INTEL_IBRIDGE_IMC_HA1_TA, 1, IMC1) }, { PCI_DESCR(PCI_DEVICE_ID_INTEL_IBRIDGE_IMC_HA1_RAS, 1, IMC1) }, { PCI_DESCR(PCI_DEVICE_ID_INTEL_IBRIDGE_IMC_HA1_TAD0, 1, IMC1) }, @@ -2291,6 +2291,13 @@ static int sbridge_get_onedevice(struct next_imc: sbridge_dev = get_sbridge_dev(bus, dev_descr->dom, multi_bus, sbridge_dev); if (!sbridge_dev) { + /* If the HA1 wasn't found, don't create EDAC second memory controller */ + if (dev_descr->dom == IMC1 && devno != 1) { + edac_dbg(0, "Skip IMC1: %04x:%04x (since HA1 was absent)\n", + PCI_VENDOR_ID_INTEL, dev_descr->dev_id); + pci_dev_put(pdev); + return 0; + }

if (dev_descr->dom == SOCK) goto out_imc;

Patches currently in stable-queue which might be from qiuxu.zhuo@intel.com are

queue-4.14/edac-sb_edac-don-t-create-a-second-memory-controller-if-ha1-is-not-present.patch