From 6429baced8a8852fee1d7fd6308653d857a9fe78 Mon Sep 17 00:00:00 2001 From: Shay Drory Date: Tue, 6 Aug 2024 10:20:44 +0300 Subject: [PATCH] genirq/irqdesc: Honor caller provided affinity in alloc_desc() BugLink: https://bugs.launchpad.net/bugs/2083656 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 Signed-off-by: Thomas Gleixner Cc: Link: https://lore.kernel.org/all/20240806072044.837827-1-shayd@nvidia.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Koichiro Den Signed-off-by: Roxana Nicolescu --- kernel/irq/irqdesc.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index 5c9888901ef4..46094f0c9fcd 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -517,6 +517,7 @@ static int alloc_descs(unsigned int start, unsigned int cnt, int node, flags = IRQD_AFFINITY_MANAGED | IRQD_MANAGED_SHUTDOWN; } + flags |= IRQD_AFFINITY_SET; mask = &affinity->mask; node = cpu_to_node(cpumask_first(mask)); affinity++;