6.15-stable review patch. If anyone has any objections, please let me know.
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From: Nuno Das Neves nunodasneves@linux.microsoft.com
[ Upstream commit bb169f80ed5a156ec3405e0e49c6b8e9ae264718 ]
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 mhklinux@outlook.com Closes: https://lore.kernel.org/linux-hyperv/SN6PR02MB4157639630F8AD2D8FD8F52FD475A@... Suggested-by: Thomas Gleixner tglx@linutronix.de Signed-off-by: Nuno Das Neves nunodasneves@linux.microsoft.com Reviewed-by: Michael Kelley mhklinux@outlook.com Link: https://lore.kernel.org/r/1751582677-30930-4-git-send-email-nunodasneves@lin... Signed-off-by: Wei Liu wei.liu@kernel.org Message-ID: 1751582677-30930-4-git-send-email-nunodasneves@linux.microsoft.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 31f0d29cbc5e3..e28c317ac9e81 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) { /*