From 5297bba507dc54045e6efeb9955c1271ca9aafe1 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Tue, 23 Jul 2024 15:27:01 +0200 Subject: [PATCH] genirq/msi: Silence 'set affinity failed' warning Various PCI controllers that mux MSIs onto a single IRQ line produce these "IRQ%d: set affinity failed" warnings when entering suspend. This has been discussed before [1] [2] and an example test case is included at the end of this commit message. Controller drivers that create MSI IRQ domain with MSI_FLAG_USE_DEF_CHIP_OPS and do not override the .irq_set_affinity() irqchip callback get assigned the default msi_domain_set_affinity() callback. That is not desired on controllers where it is not possible to set affinity of each MSI IRQ line to a specific CPU core due to hardware limitation. Introduce flag MSI_FLAG_NO_AFFINITY, which keeps .irq_set_affinity() unset if the controller driver did not assign it. This way, migrate_one_irq() can exit right away, without printing the warning. The .irq_set_affinity() implementations which only return -EINVAL can be removed from multiple controller drivers. $ grep 25 /proc/interrupts 25: 0 0 0 0 0 0 0 0 PCIe MSI 0 Edge PCIe PME $ echo core > /sys/power/pm_test ; echo mem > /sys/power/state ... Disabling non-boot CPUs ... IRQ25: set affinity failed(-22). <---------- This is being silenced here psci: CPU7 killed (polled 4 ms) ... [1] https://lore.kernel.org/all/d4a6eea3c5e33a3a4056885419df95a7@kernel.org/ [2] https://lore.kernel.org/all/5f4947b18bf381615a37aa81c2242477@kernel.org/ Link: https://lore.kernel.org/r/20240723132958.41320-2-marek.vasut+renesas@mailbox.org Signed-off-by: Marek Vasut [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas Reviewed-by: Damien Le Moal Reviewed-by: Manivannan Sadhasivam Acked-by: Thomas Gleixner --- include/linux/msi.h | 2 ++ kernel/irq/msi.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/include/linux/msi.h b/include/linux/msi.h index 944979763825..b10093c4d00e 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -554,6 +554,8 @@ enum { MSI_FLAG_MSIX_CONTIGUOUS = (1 << 19), /* PCI/MSI-X vectors can be dynamically allocated/freed post MSI-X enable */ MSI_FLAG_PCI_MSIX_ALLOC_DYN = (1 << 20), + /* PCI MSIs cannot be steered separately to CPU cores */ + MSI_FLAG_NO_AFFINITY = (1 << 21), }; /** diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c index 5fa0547ece0c..ca6e2ae6d6fc 100644 --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -832,7 +832,7 @@ static void msi_domain_update_chip_ops(struct msi_domain_info *info) struct irq_chip *chip = info->chip; BUG_ON(!chip || !chip->irq_mask || !chip->irq_unmask); - if (!chip->irq_set_affinity) + if (!chip->irq_set_affinity && !(info->flags & MSI_FLAG_NO_AFFINITY)) chip->irq_set_affinity = msi_domain_set_affinity; } -- 2.50.1