Re: [PATCH 0/2] NTB: epf: Fix ntb_hw_epf ISR issues

Dave Jiang <[email protected]> Wed, 18 Mar 2026 12:51:39 -0700
Newsgroups dev.linux.lists.ntb,org.kernel.vger.linux-kernel
Message-ID <[email protected]>

On 3/16/26 8:01 PM, Koichiro Den wrote:
> On Wed, Mar 04, 2026 at 05:30:26PM +0900, Koichiro Den wrote:
>> ntb_hw_epf handles doorbell interrupts using multiple MSI/MSI-X vectors.
>> This small patch series is to address two issues in the interrupt
>> setup/handler path:
>>
>>  1) ntb_epf_init_isr() does not unwind already requested IRQs when
>>     request_irq() fails part-way through the vector loop.
>>
>>  2) ntb_epf_vec_isr() calls pci_irq_vector() in hardirq context to
>>     derive the vector number. pci_irq_vector() performs an MSI domain
>>     lookup (msi_get_virq()) that takes a mutex, which can trigger
>>     "scheduling while atomic" splats.
>>
>> Patch 1 fixes the request_irq() unwind path.
>> Patch 2 caches the Linux IRQ number for vector 0 and uses it as a base in
>> the ISR, avoiding pci_irq_vector() from hardirq context.
>>
>> Both patches are Cc'd to stable (v5.12+).
>>
>> Best regards,
>> Koichiro
>>
>> Koichiro Den (2):
>>   NTB: epf: Fix request_irq() unwind in ntb_epf_init_isr()
>>   NTB: epf: Avoid pci_irq_vector() from hardirq context
> 
> Jon or Dave,
> 
> Gentle ping on this series.
> I would appreciate it if you could take a look when you have a chance.

For the series, LGTM
Reviewed-by: Dave Jiang <[email protected]>

> 
> Best regards,
> Koichiro
> 
>>
>>  drivers/ntb/hw/epf/ntb_hw_epf.c | 14 +++++++-------
>>  1 file changed, 7 insertions(+), 7 deletions(-)
>>
>> -- 
>> 2.51.0
>>
>>