This is a note to let you know that I've just added the patch titled
x86/pci/xen: populate MSI sysfs entries
to the 6.3-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-pci-xen-populate-msi-sysfs-entries.patch
and it can be found in the queue-6.3 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 335b4223466dd75f9f3ea4918187afbadd22e5c8 Mon Sep 17 00:00:00 2001
From: Maximilian Heyne <mheyne@xxxxxxxxx>
Date: Wed, 3 May 2023 13:16:53 +0000
Subject: x86/pci/xen: populate MSI sysfs entries
From: Maximilian Heyne <mheyne@xxxxxxxxx>
commit 335b4223466dd75f9f3ea4918187afbadd22e5c8 upstream.
Commit bf5e758f02fc ("genirq/msi: Simplify sysfs handling") reworked the
creation of sysfs entries for MSI IRQs. The creation used to be in
msi_domain_alloc_irqs_descs_locked after calling ops->domain_alloc_irqs.
Then it moved into __msi_domain_alloc_irqs which is an implementation of
domain_alloc_irqs. However, Xen comes with the only other implementation
of domain_alloc_irqs and hence doesn't run the sysfs population code
anymore.
Commit 6c796996ee70 ("x86/pci/xen: Fixup fallout from the PCI/MSI
overhaul") set the flag MSI_FLAG_DEV_SYSFS for the xen msi_domain_info
but that doesn't actually have an effect because Xen uses it's own
domain_alloc_irqs implementation.
Fix this by making use of the fallback functions for sysfs population.
Fixes: bf5e758f02fc ("genirq/msi: Simplify sysfs handling")
Signed-off-by: Maximilian Heyne <mheyne@xxxxxxxxx>
Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
Link: https://lore.kernel.org/r/20230503131656.15928-1-mheyne@xxxxxxxxx
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/pci/xen.c | 8 +++++---
include/linux/msi.h | 9 ++++++++-
kernel/irq/msi.c | 4 ++--
3 files changed, 15 insertions(+), 6 deletions(-)
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -198,7 +198,7 @@ static int xen_setup_msi_irqs(struct pci
i++;
}
kfree(v);
- return 0;
+ return msi_device_populate_sysfs(&dev->dev);
error:
if (ret == -ENOSYS)
@@ -254,7 +254,7 @@ static int xen_hvm_setup_msi_irqs(struct
dev_dbg(&dev->dev,
"xen: msi --> pirq=%d --> irq=%d\n", pirq, irq);
}
- return 0;
+ return msi_device_populate_sysfs(&dev->dev);
error:
dev_err(&dev->dev, "Failed to create MSI%s! ret=%d!\n",
@@ -346,7 +346,7 @@ static int xen_initdom_setup_msi_irqs(st
if (ret < 0)
goto out;
}
- ret = 0;
+ ret = msi_device_populate_sysfs(&dev->dev);
out:
return ret;
}
@@ -394,6 +394,8 @@ static void xen_teardown_msi_irqs(struct
xen_destroy_irq(msidesc->irq + i);
msidesc->irq = 0;
}
+
+ msi_device_destroy_sysfs(&dev->dev);
}
static void xen_pv_teardown_msi_irqs(struct pci_dev *dev)
--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -383,6 +383,13 @@ int arch_setup_msi_irq(struct pci_dev *d
void arch_teardown_msi_irq(unsigned int irq);
int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type);
void arch_teardown_msi_irqs(struct pci_dev *dev);
+#endif /* CONFIG_PCI_MSI_ARCH_FALLBACKS */
+
+/*
+ * Xen uses non-default msi_domain_ops and hence needs a way to populate sysfs
+ * entries of MSI IRQs.
+ */
+#if defined(CONFIG_PCI_XEN) || defined(CONFIG_PCI_MSI_ARCH_FALLBACKS)
#ifdef CONFIG_SYSFS
int msi_device_populate_sysfs(struct device *dev);
void msi_device_destroy_sysfs(struct device *dev);
@@ -390,7 +397,7 @@ void msi_device_destroy_sysfs(struct dev
static inline int msi_device_populate_sysfs(struct device *dev) { return 0; }
static inline void msi_device_destroy_sysfs(struct device *dev) { }
#endif /* !CONFIG_SYSFS */
-#endif /* CONFIG_PCI_MSI_ARCH_FALLBACKS */
+#endif /* CONFIG_PCI_XEN || CONFIG_PCI_MSI_ARCH_FALLBACKS */
/*
* The restore hook is still available even for fully irq domain based
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -542,7 +542,7 @@ fail:
return ret;
}
-#ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS
+#if defined(CONFIG_PCI_MSI_ARCH_FALLBACKS) || defined(CONFIG_PCI_XEN)
/**
* msi_device_populate_sysfs - Populate msi_irqs sysfs entries for a device
* @dev: The device (PCI, platform etc) which will get sysfs entries
@@ -574,7 +574,7 @@ void msi_device_destroy_sysfs(struct dev
msi_for_each_desc(desc, dev, MSI_DESC_ALL)
msi_sysfs_remove_desc(dev, desc);
}
-#endif /* CONFIG_PCI_MSI_ARCH_FALLBACK */
+#endif /* CONFIG_PCI_MSI_ARCH_FALLBACK || CONFIG_PCI_XEN */
#else /* CONFIG_SYSFS */
static inline int msi_sysfs_create_group(struct device *dev) { return 0; }
static inline int msi_sysfs_populate_desc(struct device *dev, struct msi_desc *desc) { return 0; }
Patches currently in stable-queue which might be from mheyne@xxxxxxxxx are
queue-6.3/x86-pci-xen-populate-msi-sysfs-entries.patch
