Accessing cpu_online_mask here is problematic because the cpus read lock
is not held in this context.

However, cpu_online_mask isn't needed here since the effective affinity
mask is guaranteed to be valid in this callback. So, just use
cpumask_first() to get the cpu instead of ANDing it with cpus_online_mask
unnecessarily.

Fixes: e39397d1fd68 ("x86/hyperv: implement an MSI domain for root partition")
Reported-by: Michael Kelley <[email protected]>
Closes: 
https://lore.kernel.org/linux-hyperv/sn6pr02mb4157639630f8ad2d8fd8f52fd4...@sn6pr02mb4157.namprd02.prod.outlook.com/
Suggested-by: Thomas Gleixner <[email protected]>
Signed-off-by: Nuno Das Neves <[email protected]>
---
 arch/x86/hyperv/irqdomain.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/x86/hyperv/irqdomain.c b/arch/x86/hyperv/irqdomain.c
index 31f0d29cbc5e..e28c317ac9e8 100644
--- a/arch/x86/hyperv/irqdomain.c
+++ b/arch/x86/hyperv/irqdomain.c
@@ -192,7 +192,6 @@ static void hv_irq_compose_msi_msg(struct irq_data *data, 
struct msi_msg *msg)
        struct pci_dev *dev;
        struct hv_interrupt_entry out_entry, *stored_entry;
        struct irq_cfg *cfg = irqd_cfg(data);
-       const cpumask_t *affinity;
        int cpu;
        u64 status;
 
@@ -204,8 +203,7 @@ static void hv_irq_compose_msi_msg(struct irq_data *data, 
struct msi_msg *msg)
                return;
        }
 
-       affinity = irq_data_get_effective_affinity_mask(data);
-       cpu = cpumask_first_and(affinity, cpu_online_mask);
+       cpu = cpumask_first(irq_data_get_effective_affinity_mask(data));
 
        if (data->chip_data) {
                /*
-- 
2.34.1


Reply via email to