Re: common_interrupt: No irq handler for vector

From: Shuah Khan
Date: Mon Dec 14 2020 - 15:58:49 EST


On 12/14/20 1:41 PM, Thomas Gleixner wrote:
On Mon, Dec 14 2020 at 09:11, Shuah Khan wrote:
On 12/12/20 12:33 PM, Thomas Gleixner wrote:
On Fri, Dec 11 2020 at 13:41, Shuah Khan wrote:

I am debugging __common_interrupt: 1.55 No irq handler for vector
messages and noticed comments and code don't agree:

I bet that's on an AMD system with broken AGESA BIOS.... Good luck
debugging it :) BIOS updates are on the way so I'm told.

Interesting. The behavior I am seeing doesn't seem to be consistent
with BIOS problem. I don't see these messages on 5.10-rc7. I started
seeing them on stable releases. It started right around 5.9.9 and
not present on 5.9.7.

What kind of machine?

Here is the processor and BIOS info:
AMD Ryzen 7 4700G with Radeon Graphics
LENOVO ThinkCentre Embedded Controller -[O4ZCT12A-1.12]-
LENOVO ThinkCentre BIOS Boot Block Revision 1.1C


I am bisecting to isolate. Same issue on all stables 5.4, 4.19 and
so on. If it is BIOS problem I would expect to see it on 5.10-rc7
and wouldn't have expected to start seeing it 5.9.9.

Can you provide some more details, e.g. dmesg please?


__common_interrupt: 1.55 No irq handler for vector
__common_interrupt: 2.55 No irq handler for vector
__common_interrupt: 3.55 No irq handler for vector
__common_interrupt: 4.55 No irq handler for vector
__common_interrupt: 5.55 No irq handler for vector
__common_interrupt: 6.55 No irq handler for vector
__common_interrupt: 7.55 No irq handler for vector
__common_interrupt: 8.55 No irq handler for vector
__common_interrupt: 9.55 No irq handler for vector
__common_interrupt: 10.55 No irq handler for vector

No. It's perfectly correct in the MSI code. See further down.

if (IS_ERR_OR_NULL(this_cpu_read(vector_irq[cfg->vector])))
this_cpu_write(vector_irq[cfg->vector], VECTOR_RETRIGGERED);


I am asking about inconsistent comments and the actual message as the
comment implies if vector is VECTOR_UNUSED state, this message won't
be triggered in common_interrupt. Based on that my read is the comment
might be wrong if the code is correct as you are saying.

The comment says:

>> * anyway. If the vector is unused, then it is marked so it won't
>> * trigger the 'No irq handler for vector' warning in
>> * common_interrupt().

If the vector is unused, then it is _marked_ so ....

See the messages above.


It perhaps should explicitely say 'is marked as VECTOR_RETRIGGERED' to make
it clear.


Possibly. I am running bisect starting at v5.9.7 (good) and compare with
v5.9.13 and see why this problems started showing up.

thanks,
-- Shuah