From: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Date: Thu, 31 Jul 2025 14:55:33 +0000 (+0800)
Subject: EDAC/i10nm: Reallocate skx_dev list if preconfigured cnt != runtime cnt
X-Git-Tag: v6.18-rc1~194^2~12
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=f7a29a37373baa0bd0823a5d55e97dc7f75a4dab;p=thirdparty%2Fkernel%2Fstable.git

EDAC/i10nm: Reallocate skx_dev list if preconfigured cnt != runtime cnt

Ideally, read the present DDR memory controller count first and then
allocate the skx_dev list using this count. However, this approach
requires adding a significant amount of code similar to
skx_get_all_bus_mappings() to obtain the PCI bus mappings for the first
socket and use these mappings along with the related PCI register offset
to read the memory controller count.

Given that the Granite Rapids CPU is the only one that can detect the
count of memory controllers at runtime (other CPUs use the count in the
configuration data), to reduce code complexity, reallocate the skx_dev
list only if the preconfigured count of DDR memory controllers differs
from the count read at runtime for Granite Rapids CPU.

Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20250731145534.2759334-7-qiuxu.zhuo@intel.com
---

diff --git a/drivers/edac/i10nm_base.c b/drivers/edac/i10nm_base.c
index 9d00f247f4e0e..2010a47149f44 100644
--- a/drivers/edac/i10nm_base.c
+++ b/drivers/edac/i10nm_base.c
@@ -468,17 +468,18 @@ static int i10nm_get_imc_num(struct res_config *cfg)
 			return -ENODEV;
 		}
 
-		if (imc_num > I10NM_NUM_DDR_IMC) {
-			i10nm_printk(KERN_ERR, "Need to make I10NM_NUM_DDR_IMC >= %d\n", imc_num);
-			return -EINVAL;
-		}
-
 		if (cfg->ddr_imc_num != imc_num) {
 			/*
-			 * Store the number of present DDR memory controllers.
+			 * Update the configuration data to reflect the number of
+			 * present DDR memory controllers.
 			 */
 			cfg->ddr_imc_num = imc_num;
 			edac_dbg(2, "Set DDR MC number: %d", imc_num);
+
+			/* Release and reallocate skx_dev list with the updated number. */
+			skx_remove();
+			if (skx_get_all_bus_mappings(cfg, &i10nm_edac_list) <= 0)
+				return -ENODEV;
 		}
 
 		return 0;