From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-Path: From: Jork Loeser To: jloeser@microsoft.com, helgaas@kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, olaf@aepfle.de, apw@canonical.com, vkuznets@redhat.com, jasowang@redhat.com, leann.ogasawara@canonical.com, marcelo.cerri@canonical.com, sthemmin@microsoft.com Subject: [PATCH 2/4] Hyper-V vPCI: Use page allocation for hbus structure Date: Thu, 18 May 2017 12:14:28 -0700 Message-Id: <1495134870-18225-3-git-send-email-jloeser@linuxonhyperv.com> In-Reply-To: <1495134870-18225-1-git-send-email-jloeser@linuxonhyperv.com> References: <1495134870-18225-1-git-send-email-jloeser@linuxonhyperv.com> Reply-To: Jork Loeser List-ID: From: Jork Loeser 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 --- drivers/pci/host/pci-hyperv.c | 12 +++++++++--- 1 files changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c index 7bebdc6..aa836e9 100644 --- a/drivers/pci/host/pci-hyperv.c +++ b/drivers/pci/host/pci-hyperv.c @@ -2204,7 +2204,13 @@ 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 +2314,7 @@ 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 +2392,7 @@ 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; } -- 1.7.1