From: Jork Loeser <jloeser@xxxxxxxxxxxxx>
The hv_pcibus_device structure contains an in-memory hypercall argument
that must not cross a page boundary. Allocate the structure as a page
to ensure that.
Signed-off-by: Jork Loeser <jloeser@xxxxxxxxxxxxx>
---
drivers/pci/host/pci-hyperv.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c
index 7bebdc6..6e4b026 100644
--- a/drivers/pci/host/pci-hyperv.c
+++ b/drivers/pci/host/pci-hyperv.c
@@ -382,7 +382,10 @@ struct hv_pcibus_device {
struct msi_domain_info msi_info;
struct msi_controller msi_chip;
struct irq_domain *irq_domain;
+
+ /* hypercall arg, must not cross page boundary */
struct retarget_msi_interrupt retarget_msi_interrupt_params;
+
spinlock_t retarget_msi_interrupt_lock;
};
@@ -2204,7 +2207,13 @@ static int hv_pci_probe(struct hv_device *hdev,
struct hv_pcibus_device *hbus;
int ret;
- hbus = kzalloc(sizeof(*hbus), GFP_KERNEL);
+ /*
+ * hv_pcibus_device contains the hypercall arguments for retargeting in
+ * hv_irq_unmask(). Those must not cross a page boundary.
+ */
+ BUILD_BUG_ON(sizeof(*hbus) > PAGE_SIZE);
+
+ hbus = (struct hv_pcibus_device *)get_zeroed_page(GFP_KERNEL);
if (!hbus)
return -ENOMEM;
hbus->state = hv_pcibus_init;
@@ -2308,7 +2317,7 @@ static int hv_pci_probe(struct hv_device *hdev,
close:
vmbus_close(hdev->channel);
free_bus:
- kfree(hbus);
+ free_page((unsigned long)hbus);
return ret;
}
@@ -2386,7 +2395,7 @@ static int hv_pci_remove(struct hv_device *hdev)
irq_domain_free_fwnode(hbus->sysdata.fwnode);
put_hvpcibus(hbus);
wait_for_completion(&hbus->remove_event);
- kfree(hbus);
+ free_page((unsigned long)hbus);
return 0;
}
--
2.7.4
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