6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Shay Drory shayd@nvidia.com
commit edbbaae42a56f9a2b39c52ef2504dfb3fb0a7858 upstream.
Currently, whenever a caller is providing an affinity hint for an interrupt, the allocation code uses it to calculate the node and copies the cpumask into irq_desc::affinity.
If the affinity for the interrupt is not marked 'managed' then the startup of the interrupt ignores irq_desc::affinity and uses the system default affinity mask.
Prevent this by setting the IRQD_AFFINITY_SET flag for the interrupt in the allocator, which causes irq_setup_affinity() to use irq_desc::affinity on interrupt startup if the mask contains an online CPU.
[ tglx: Massaged changelog ]
Fixes: 45ddcecbfa94 ("genirq: Use affinity hint in irqdesc allocation") Signed-off-by: Shay Drory shayd@nvidia.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20240806072044.837827-1-shayd@nvidia.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- kernel/irq/irqdesc.c | 1 + 1 file changed, 1 insertion(+)
--- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -517,6 +517,7 @@ static int alloc_descs(unsigned int star flags = IRQD_AFFINITY_MANAGED | IRQD_MANAGED_SHUTDOWN; } + flags |= IRQD_AFFINITY_SET; mask = &affinity->mask; node = cpu_to_node(cpumask_first(mask)); affinity++;