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genirq/msi, platform-msi: Ensure that MSI descriptors are unreferenced

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Miquel reported a warning in the MSI core which is triggered when
interrupts are freed via platform_msi_device_domain_free().

This code got reworked to use core functions for freeing the MSI
descriptors, but nothing took care to clear the msi_desc->irq entry, which
then triggers the warning in msi_free_msi_desc() which uses desc->irq to
validate that the descriptor has been torn down. The same issue exists in
msi_domain_populate_irqs().

Up to the point that msi_free_msi_descs() grew a warning for this case,
this went un-noticed.

Provide the counterpart of msi_domain_populate_irqs() and invoke it in
platform_msi_device_domain_free() before freeing the interrupts and MSI
descriptors and also in the error path of msi_domain_populate_irqs().

Fixes: 2f2940d16823 ("genirq/msi: Remove filter from msi_free_descs_free_range()")
Reported-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87mt4wkwnv.ffs@tglx
This commit is contained in:
Thomas Gleixner 2023-03-01 22:07:48 +01:00
parent ea9a78c3a7
commit 0fb7fb7134
3 changed files with 25 additions and 1 deletions
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1
drivers/base/platform-msi.c
View File

@ -324,6 +324,7 @@ void platform_msi_device_domain_free(struct irq_domain *domain, unsigned int vir
struct platform_msi_priv_data *data = domain->host_data;
msi_lock_descs(data->dev);
msi_domain_depopulate_descs(data->dev, virq, nr_irqs);
irq_domain_free_irqs_common(domain, virq, nr_irqs);
msi_free_msi_descs_range(data->dev, virq, virq + nr_irqs - 1);
msi_unlock_descs(data->dev);

2
include/linux/msi.h
View File

@ -631,6 +631,8 @@ int msi_domain_prepare_irqs(struct irq_domain *domain, struct device *dev,
int nvec, msi_alloc_info_t *args);
int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev,
int virq, int nvec, msi_alloc_info_t *args);
void msi_domain_depopulate_descs(struct device *dev, int virq, int nvec);
struct irq_domain *
__platform_msi_create_device_domain(struct device *dev,
unsigned int nvec,

23
kernel/irq/msi.c
View File

@ -1109,14 +1109,35 @@ int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev,
return 0;
fail:
for (--virq; virq >= virq_base; virq--)
for (--virq; virq >= virq_base; virq--) {
msi_domain_depopulate_descs(dev, virq, 1);
irq_domain_free_irqs_common(domain, virq, 1);
}
msi_domain_free_descs(dev, &ctrl);
unlock:
msi_unlock_descs(dev);
return ret;
}
void msi_domain_depopulate_descs(struct device *dev, int virq_base, int nvec)
{
struct msi_ctrl ctrl = {
.domid = MSI_DEFAULT_DOMAIN,
.first = virq_base,
.last = virq_base + nvec - 1,
};
struct msi_desc *desc;
struct xarray *xa;
unsigned long idx;
if (!msi_ctrl_valid(dev, &ctrl))
return;
xa = &dev->msi.data->__domains[ctrl.domid].store;
xa_for_each_range(xa, idx, desc, ctrl.first, ctrl.last)
desc->irq = 0;
}
/*
* Carefully check whether the device can use reservation mode. If
* reservation mode is enabled then the early activation will assign a