diff options
author | Koichiro Den <den@valinux.co.jp> | 2023-10-26 12:20:36 +0900 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2023-10-26 13:53:06 +0200 |
commit | b56ebe7c896dc78b5865ec2c4b1dae3c93537517 (patch) | |
tree | 4d5150ec2ca93a7232695f808aa2ebd93309c7c5 /kernel/irq/msi.c | |
parent | 441ccc351256533b6381e86a5648dbfe04b74286 (diff) | |
download | lwn-b56ebe7c896dc78b5865ec2c4b1dae3c93537517.tar.gz lwn-b56ebe7c896dc78b5865ec2c4b1dae3c93537517.zip |
x86/apic/msi: Fix misconfigured non-maskable MSI quirk
commit ef8dd01538ea ("genirq/msi: Make interrupt allocation less
convoluted"), reworked the code so that the x86 specific quirk for affinity
setting of non-maskable PCI/MSI interrupts is not longer activated if
necessary.
This could be solved by restoring the original logic in the core MSI code,
but after a deeper analysis it turned out that the quirk flag is not
required at all.
The quirk is only required when the PCI/MSI device cannot mask the MSI
interrupts, which in turn also prevents reservation mode from being enabled
for the affected interrupt.
This allows ot remove the NOMASK quirk bit completely as msi_set_affinity()
can instead check whether reservation mode is enabled for the interrupt,
which gives exactly the same answer.
Even in the momentary non-existing case that the reservation mode would be
not set for a maskable MSI interrupt this would not cause any harm as it
just would cause msi_set_affinity() to go needlessly through the
functionaly equivalent slow path, which works perfectly fine with maskable
interrupts as well.
Rework msi_set_affinity() to query the reservation mode and remove all
NOMASK quirk logic from the core code.
[ tglx: Massaged changelog ]
Fixes: ef8dd01538ea ("genirq/msi: Make interrupt allocation less convoluted")
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Koichiro Den <den@valinux.co.jp>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20231026032036.2462428-1-den@valinux.co.jp
Diffstat (limited to 'kernel/irq/msi.c')
-rw-r--r-- | kernel/irq/msi.c | 12 |
1 files changed, 1 insertions, 11 deletions
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c index b4c31a5c1147..79b4a58ba9c3 100644 --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -1204,7 +1204,6 @@ static int msi_handle_pci_fail(struct irq_domain *domain, struct msi_desc *desc, #define VIRQ_CAN_RESERVE 0x01 #define VIRQ_ACTIVATE 0x02 -#define VIRQ_NOMASK_QUIRK 0x04 static int msi_init_virq(struct irq_domain *domain, int virq, unsigned int vflags) { @@ -1213,8 +1212,6 @@ static int msi_init_virq(struct irq_domain *domain, int virq, unsigned int vflag if (!(vflags & VIRQ_CAN_RESERVE)) { irqd_clr_can_reserve(irqd); - if (vflags & VIRQ_NOMASK_QUIRK) - irqd_set_msi_nomask_quirk(irqd); /* * If the interrupt is managed but no CPU is available to @@ -1275,15 +1272,8 @@ static int __msi_domain_alloc_irqs(struct device *dev, struct irq_domain *domain * Interrupt can use a reserved vector and will not occupy * a real device vector until the interrupt is requested. */ - if (msi_check_reservation_mode(domain, info, dev)) { + if (msi_check_reservation_mode(domain, info, dev)) vflags |= VIRQ_CAN_RESERVE; - /* - * MSI affinity setting requires a special quirk (X86) when - * reservation mode is active. - */ - if (info->flags & MSI_FLAG_NOMASK_QUIRK) - vflags |= VIRQ_NOMASK_QUIRK; - } xa_for_each_range(xa, idx, desc, ctrl->first, ctrl->last) { if (!msi_desc_match(desc, MSI_DESC_NOTASSOCIATED)) |