Re: [PATCH v3 3/3] amdgpu: don't report an error if the process was killed

["Christian König" <christian.koenig@amd.com>]

On 1/5/26 19:20, Liam R. Howlett wrote:
> * Mikulas Patocka <mpatocka@redhat.com> [260104 16:18]:
>> If the process was killed by a fatal signal, amdgpu_hmm_register could
>> return -EINTR (the -EINTR comes from mm_take_all_locks).
>>
>> Don't log the error in this case, because no error happened.
>>
>> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
>>
>> ---
>>  drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c |    9 +++++++--
>>  1 file changed, 7 insertions(+), 2 deletions(-)
>>
>> Index: mm/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
>> ===================================================================
>> --- mm.orig/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c	2026-01-04 21:19:14.000000000 +0100
>> +++ mm/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c	2026-01-04 21:19:14.000000000 +0100
>> @@ -1070,8 +1070,13 @@ static int init_user_pages(struct kgd_me
>>  
>>  	ret = amdgpu_hmm_register(bo, user_addr);
>>  	if (ret) {
>> -		pr_err("%s: Failed to register MMU notifier: %d\n",
>> -		       __func__, ret);
>> +		/*
>> +		 * If we got EINTR because the process was killed, don't report
>> +		 * it, because no error happened.
>> +		 */
>> +		if (!(fatal_signal_pending(current) && ret == -EINTR))
>> +			pr_err("%s: Failed to register MMU notifier: %d\n",
>> +			       __func__, ret);
> 
> Masking off error messages will make the message less useful and harder
> to debug.

Reporting errors on -EINTR and -ERESTARTSYS are usually considered a bug since that are perfectly normal conditions to occur.

> You could also change the log level, which might be more desirable for a
> whole lot of the messages in here?

Well I agree that debug or info level is probably more suitable, but error messages like this here are just a symptom that people doesn't know how to properly use ftrace.

In other words when you have a message in syslog that userspace did something wrong, even if it's just a debug message, than that is in like 99% of all cases not appropriate.

What drivers should log is things like HW conditions changes, global SW condition changes because somebody requested feature X, performance changes because of I have to enable workaround Y...... but not system call is interrupted by signal, application is using to much memory or giving invalid values etc....

Regards,
Christian.

> 
> Thanks,
> Liam