Re: [PATCH v4 1/2] efi/cper: add cper_mem_err_status_str to decode error description

Shuai Xue
2022-01-26T05:25:36Z

Hi, Borislav,

Thank you for your comments.

在 2022/1/26 AM3:08, Borislav Petkov 写道:
> On Tue, Jan 25, 2022 at 10:49:38AM +0800, Shuai Xue wrote:
>> Introduce a new helper function cper_mem_err_status_str() which is used to
>> decode the description of error status, and the cper_print_mem() will call
>> it and report the details of error status.
>>
>> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
>> ---
>> drivers/firmware/efi/cper.c | 29 ++++++++++++++++++++++++++++-
>> include/linux/cper.h | 1 +
>> 2 files changed, 29 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/firmware/efi/cper.c b/drivers/firmware/efi/cper.c
>> index 6ec8edec6329..7f08d4ea906e 100644
>> --- a/drivers/firmware/efi/cper.c
>> +++ b/drivers/firmware/efi/cper.c
>> @@ -211,6 +211,31 @@ const char *cper_mem_err_type_str(unsigned int etype)
>> }
>> EXPORT_SYMBOL_GPL(cper_mem_err_type_str);
>>
>> +const char *cper_mem_err_status_str(u64 status)
>> +{
>> + switch ((status >> 8) & 0xff) {
>> + case 1: return "Error detected internal to the component";
>> + case 4: return "Storage error in DRAM memory";
>> + case 5: return "Storage error in TLB";
>> + case 6: return "Storage error in cache";
>> + case 7: return "Error in one or more functional units";
>> + case 8: return "component failed self test";
>
> Well, at least start them all with capital letters: "Component... " And
> yes, I know this is how it is in the spec but the spec has typos and
> other problems - doesn't mean we have to copy them too.

You are right, I will fix it in next version.

>> + case 9: return "Overflow or undervalue of internal queue";
>> + case 16: return "Error detected in the bus";
>> + case 17: return "Virtual address not found on IO-TLB or IO-PDIR";
>> + case 18: return "Improper access error";
>> + case 19: return "Access to a memory address which is not mapped to any component";
>> + case 20: return "Loss of Lockstep";
>> + case 21: return "Response not associated with a request";
>> + case 22: return "Bus parity error - must also set the A, C, or D Bits";
>> + case 23: return "Detection of a PATH_ERROR ";
>
> Trailing space here.

Sorry, will delete it.

> Also what is PATH_ERROR?
>
> That "PATH_ERROR" is nowhere else explained in that big fat UEFI spec.
> 2558 pages and they can't explain *that*. Geez.

I don't know either. A related item I found is "iSCSI Device Path error".
Section 10 defines the device path protocol, but I don't know if "PATH_ERROR"
means the path of the device is not found, or something else.

>> + case 25: return "Bus operation timeout";
>> + case 26: return "A read was issued to data that has been poisoned";
>> + default: return "reserved";
>> + }
>> +}
>> +EXPORT_SYMBOL_GPL(cper_mem_err_status_str);
>> +
>> static int cper_mem_err_location(struct cper_mem_err_compact *mem, char *msg)
>> {
>> u32 len, n;
>> @@ -334,7 +359,9 @@ static void cper_print_mem(const char *pfx, const struct cper_sec_mem_err *mem,
>> return;
>> }
>> if (mem->validation_bits & CPER_MEM_VALID_ERROR_STATUS)
>> - printk("%s""error_status: 0x%016llx\n", pfx, mem->error_status);
>> + printk("%s""error_status: %s (0x%016llx)\n",
>
> Why do you insist on having two back-to-back strings instead of one
> here?
>
> (And don't tell me it is because the other function calls here do it
> too.)
>
> FWIW, even checkpatch complains here:
>
> WARNING: Consecutive strings are generally better as a single string
> #87: FILE: drivers/firmware/efi/cper.c:362:
> + printk("%s""error_status: %s (0x%016llx)\n",
>
> Btw, please integrate scripts/checkpatch.pl into your patch creation
> workflow. Some of the warnings/errors *actually* make sense.

Sorry, I did integrate scripts/checkpatch.pl before sending patch. And as you see,
other function calls here do the same, so I ignored the warnings. I will change as
your comments in next version:

- printk("%s""error_status: 0x%016llx\n", pfx, mem->error_status);
+ printk("%s error_status: %s (0x%016llx)\n",

Best regards,
Shuai