Re: [PATCH 1/3] x86/MCE/AMD: Split amd_mce_is_memory_error()

[Shuai Xue]

On 2023/6/13 22:11, Yazen Ghannam wrote:
> Define helper functions for legacy and SMCA systems in order to reuse
> individual checks in later changes.
> 
> Describe what each function is checking for, and correct the XEC bitmask
> for SMCA.
> 
> No functional change intended.
> 
> Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
> ---
>  arch/x86/kernel/cpu/mce/amd.c | 30 +++++++++++++++++++++++++-----
>  1 file changed, 25 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c
> index 5e74610b39e7..1ccfb0c9257f 100644
> --- a/arch/x86/kernel/cpu/mce/amd.c
> +++ b/arch/x86/kernel/cpu/mce/amd.c
> @@ -713,17 +713,37 @@ void mce_amd_feature_init(struct cpuinfo_x86 *c)
>  		deferred_error_interrupt_enable(c);
>  }
>  
> -bool amd_mce_is_memory_error(struct mce *m)
> +/*
> + * DRAM ECC errors are reported in the Northbridge (bank 4) with
> + * Extended Error Code 8.
> + */
> +static bool legacy_mce_is_memory_error(struct mce *m)
> +{
> +	return m->bank == 4 && XEC(m->status, 0x1f) == 8;
> +}
> +
> +/*
> + * DRAM ECC errors are reported in Unified Memory Controllers with
> + * Extended Error Code 0.
> + */
> +static bool smca_mce_is_memory_error(struct mce *m)
>  {
>  	enum smca_bank_types bank_type;
> -	/* ErrCodeExt[20:16] */
> -	u8 xec = (m->status >> 16) & 0x1f;
> +
> +	if (XEC(m->status, 0x3f))
> +		return false;
>  
>  	bank_type = smca_get_bank_type(m->extcpu, m->bank);
> +
> +	return bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2;
> +}
> +
> +bool amd_mce_is_memory_error(struct mce *m)
> +{
>  	if (mce_flags.smca)
> -		return (bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2) && xec == 0x0;
> +		return smca_mce_is_memory_error(m);
>  
> -	return m->bank == 4 && xec == 0x8;
> +	return legacy_mce_is_memory_error(m);
>  }
>  
>  static void __log_error(unsigned int bank, u64 status, u64 addr, u64 misc)

Hi, Yazen,

Which tree are you working on? This patch can not be applied to Linus master ?
(commit b6dad5178ceaf23f369c3711062ce1f2afc33644)

Thanks.

Best Regards,
Shuai