From be66b673659116930f2da2f41ec79c9d1279cd8f Mon Sep 17 00:00:00 2001 From: Jork Loeser Date: Wed, 24 May 2017 13:41:25 -0700 Subject: [PATCH] PCI: hv: Use page allocation for hbus structure 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 Signed-off-by: Bjorn Helgaas Reviewed-by: K. Y. Srinivasan Acked-by: K. Y. Srinivasan --- 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 7bebdc6f6152..6e4b02678b7a 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 @@ free_config: 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; }