Re: [PATCH v2 2/2] kexec: fix error propagation in kexec_image_probe_default()

[Pratyush Yadav <pratyush@kernel.org>]

On Thu, Aug 20 2026, Philipp Rudo wrote:

> Hi Mukesh,
> Hi Pratyush,
>
> having this patch makes sense. Personally I'd go with having a
> switch-case rather than individual if-blocks. E.g.
>
> 	switch (ret) {
> 		case 0:
> 			image->fops = *fops;
> 			return 0;
> 		case -ENOEXEC:
> 			continue;
> 		default:
> 			return ret;
> 	}
>
> IMHO that is better readable and easier to extend in case other error
> codes need special handling as well. But that is only my personal
> opinion.

Well, IMO both look roughly the same so I unless Mukesh prefers your
version more, we can keep it as-is.

>
> Independent on which implementation you use.
>
> Reviewed-by: Philipp Rudo <prudo@redhat.com>

Thanks for reviewing!

One tiny suggestion. Can you please reply in-line the next time around?
It is a bit easier reading this response below the code that it refers
to.

>
>
> On Wed, 19 Aug 2026 23:17:23 +0530
> Mukesh Pilaniya <mpilaniy@redhat.com> wrote:
>
>> kexec_image_probe_default() overwrites ret with each loader's probe
>> return value and returns whatever the last loader returned when no
>> probe matches.  The error code reaching userspace depends on whichever
>> loader happens to be last in kexec_file_loaders[].
>> 
>> Only continue to the next loader when a probe returns -ENOEXEC.
>> Propagate any other error such as -ENOMEM immediately. Return -ENOEXEC
>> only when all loaders have been tried and none matched.
>> 
>> Suggested-by: Pratyush Yadav <pratyush@kernel.org>
>> Signed-off-by: Mukesh Pilaniya <mpilaniy@redhat.com>
>> ---
>>  kernel/kexec_file.c | 12 +++++++-----
>>  1 file changed, 7 insertions(+), 5 deletions(-)
>> 
>> diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
>> index 59fb9d71e9d8..b3060e984ef3 100644
>> --- a/kernel/kexec_file.c
>> +++ b/kernel/kexec_file.c
>> @@ -68,17 +68,19 @@ int kexec_image_probe_default(struct kimage *image, void *buf,
>>  			      unsigned long buf_len)
>>  {
>>  	const struct kexec_file_ops * const *fops;
>> -	int ret = -ENOEXEC;
>>  
>>  	for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) {
>> -		ret = (*fops)->probe(buf, buf_len);
>> -		if (!ret) {
>> +		int ret = (*fops)->probe(buf, buf_len);
>> +
>> +		if (ret == 0) {
>>  			image->fops = *fops;
>> -			return ret;
>> +			return 0;
>>  		}
>> +		if (ret != -ENOEXEC)
>> +			return ret;
>>  	}
>>  
>> -	return ret;
>> +	return -ENOEXEC;
>>  }
>>  
>>  static void *kexec_image_load_default(struct kimage *image)
>> 
>

-- 
Regards,
Pratyush Yadav