[PATCH 6.18 275/333] powerpc/pseries: Correct MSI allocation tracking

Greg Kroah-Hartman
2026-03-17T17:24:48Z

From: Nam Cao <namcao@linutronix.de>

commit 35e4f2a17eb40288f9bcdb09549fa04a63a96279 upstream.

The per-device MSI allocation calculation in pseries_irq_domain_alloc()
is clearly wrong. It can still happen to work when nr_irqs is 1.

Correct it.

Fixes: c0215e2d72de ("powerpc/pseries: Fix MSI-X allocation failure when quota is exceeded")
Cc: stable@vger.kernel.org
Signed-off-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
[maddy: Fixed Nilay's reviewed-by tag]
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260302003948.1452016-1-namcao@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/powerpc/platforms/pseries/msi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/powerpc/platforms/pseries/msi.c
+++ b/arch/powerpc/platforms/pseries/msi.c
@@ -605,7 +605,7 @@ static int pseries_irq_domain_alloc(stru
&pseries_msi_irq_chip, pseries_dev);
}

- pseries_dev->msi_used++;
+ pseries_dev->msi_used += nr_irqs;
return 0;