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

From: Shuai Xue
Date: Wed Jun 14 2023 - 22:03:13 EST




On 2023/6/14 23:06, Yazen Ghannam wrote:
> On 6/13/2023 10:06 PM, Shuai Xue wrote:
>>
>>
>> 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)
>>
>
> Hi Shuai,
>
> I'm using tip/master as the base.
> https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/log/
>
> Sorry, I forgot to mention this in the cover letter.

Ok. This patch itself looks good to me.

Reviewed-by: Shuai Xue <xueshuai@xxxxxxxxxxxxxxxxx>

Thanks.
Shuai