The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From ee470bb25d0dcdf126f586ec0ae6dca66cb340a4 Mon Sep 17 00:00:00 2001

From: Borislav Petkov bp@suse.de Date: Thu, 18 Jun 2020 20:25:25 +0200 Subject: [PATCH] EDAC/amd64: Read back the scrub rate PCI register on F15h

Commit:

da92110dfdfa ("EDAC, amd64_edac: Extend scrub rate support to F15hM60h")

added support for F15h, model 0x60 CPUs but in doing so, missed to read back SCRCTRL PCI config register on F15h CPUs which are *not* model 0x60. Add that read so that doing

$ cat /sys/devices/system/edac/mc/mc0/sdram_scrub_rate

can show the previously set DRAM scrub rate.

Fixes: da92110dfdfa ("EDAC, amd64_edac: Extend scrub rate support to F15hM60h") Reported-by: Anders Andersson pipatron@gmail.com Signed-off-by: Borislav Petkov bp@suse.de Cc: stable@vger.kernel.org #v4.4.. Link: https://lkml.kernel.org/r/CAKkunMbNWppx_i6xSdDHLseA2QQmGJqj_crY=NF-GZML5np4V...

diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c index ef90070a9194..6262f6370c5d 100644 --- a/drivers/edac/amd64_edac.c +++ b/drivers/edac/amd64_edac.c @@ -269,6 +269,8 @@ static int get_scrub_rate(struct mem_ctl_info *mci)

if (pvt->model == 0x60) amd64_read_pci_cfg(pvt->F2, F15H_M60H_SCRCTRL, &scrubval); + else + amd64_read_pci_cfg(pvt->F3, SCRCTRL, &scrubval); } else { amd64_read_pci_cfg(pvt->F3, SCRCTRL, &scrubval); }