Starting Zen4, AMD SOCs have 12 Unified Memory Controllers (UMCs) per socket.

When the amd64_edac module is being loaded, these UMCs are traversed to determine if they have SdpInit (SdpCtrl[31]) and EccEnabled (UmcCapHi[30]) bits set and create masks in umc_en_mask and ecc_en_mask respectively.

However, the current data type of these variables is u8. As a result, if only the last 4 UMCs (UMC8 - UMC11) of the system have been utilized, umc_ecc_enabled() will return false. Consequently, the module may fail to load on these systems.

Fixes: e2be5955a886 ("EDAC/amd64: Add support for AMD Family 19h Models 10h-1Fh and A0h-AFh") Signed-off-by: Avadhut Naik avadhut.naik@amd.com Cc: stable@vger.kernel.org --- Changes in v2: 1. Change data type of variables from u16 to int. (Boris) 2. Modify commit message per feedback. (Boris) 3. Add Fixes: and CC:stable tags. (Boris) --- drivers/edac/amd64_edac.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c index ddfbdb66b794..b1c034214a8d 100644 --- a/drivers/edac/amd64_edac.c +++ b/drivers/edac/amd64_edac.c @@ -3362,7 +3362,7 @@ static bool dct_ecc_enabled(struct amd64_pvt *pvt)

static bool umc_ecc_enabled(struct amd64_pvt *pvt) { - u8 umc_en_mask = 0, ecc_en_mask = 0; + int umc_en_mask = 0, ecc_en_mask = 0; u16 nid = pvt->mc_node_id; struct amd64_umc *umc; u8 ecc_en = 0, i;

base-commit: f84722cbed6c2b2094ad8bbe48be2c5900752935