diff options
| author | Will McVicker <willmcvicker@google.com> | 2022-06-13 17:26:11 -0500 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2022-08-01 15:15:32 -0500 |
| commit | 35797e672ff0610224d80e3cc08393fef1032f9a (patch) | |
| tree | ba6cd700d9cc9188a557c8f2fb252765f5fa6667 /drivers/pci/controller/dwc | |
| parent | ce06bf570390fb8b41d581e5d594727b51367179 (diff) | |
| download | linux-35797e672ff0610224d80e3cc08393fef1032f9a.tar.bz2 | |
PCI: dwc: Fix MSI msi_msg DMA mapping
As of 07940c369a6b ("PCI: dwc: Fix MSI page leakage in suspend/resume"),
the PCIe designware host driver has been using the driver data allocation
for the msi_msg DMA mapping which can result in a DMA_MAPPING_ERROR due to
the DMA overflow check in dma_direct_map_page() when the address is greater
than 32 bits (reported in [1]). The commit was trying to address a memory
leak on suspend/resume by moving the MSI mapping to dw_pcie_host_init(),
but subsequently dropped the page allocation thinking it wasn't needed.
To fix the DMA mapping issue as well as make msi_msg DMA'able, switch back
to allocating a 32-bit page for the msi_msg. To avoid the suspend/resume
leak, allocate the page in dw_pcie_host_init() since that shouldn't be
called during suspend/resume.
[1] https://lore.kernel.org/all/Yo0soniFborDl7+C@google.com/
Signed-off-by: Will McVicker <willmcvicker@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Diffstat (limited to 'drivers/pci/controller/dwc')
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-designware-host.c | 14 | ||||
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-designware.h | 2 |
2 files changed, 9 insertions, 7 deletions
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c index 6993ce9e856d..ff3451a6b846 100644 --- a/drivers/pci/controller/dwc/pcie-designware-host.c +++ b/drivers/pci/controller/dwc/pcie-designware-host.c @@ -267,8 +267,9 @@ static void dw_pcie_free_msi(struct dw_pcie_rp *pp) struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct device *dev = pci->dev; - dma_unmap_single_attrs(dev, pp->msi_data, sizeof(pp->msi_msg), - DMA_FROM_DEVICE, DMA_ATTR_SKIP_CPU_SYNC); + dma_unmap_page(dev, pp->msi_data, PAGE_SIZE, DMA_FROM_DEVICE); + if (pp->msi_page) + __free_page(pp->msi_page); } } @@ -395,13 +396,14 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp) if (ret) dev_warn(dev, "Failed to set DMA mask to 32-bit. Devices with only 32-bit MSI support may not work properly\n"); - pp->msi_data = dma_map_single_attrs(dev, &pp->msi_msg, - sizeof(pp->msi_msg), - DMA_FROM_DEVICE, - DMA_ATTR_SKIP_CPU_SYNC); + pp->msi_page = alloc_page(GFP_DMA32); + pp->msi_data = dma_map_page(dev, pp->msi_page, 0, + PAGE_SIZE, DMA_FROM_DEVICE); ret = dma_mapping_error(dev, pp->msi_data); if (ret) { dev_err(pci->dev, "Failed to map MSI data\n"); + __free_page(pp->msi_page); + pp->msi_page = NULL; pp->msi_data = 0; goto err_free_msi; } diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h index c3e73ed9aff5..7c63204d23ba 100644 --- a/drivers/pci/controller/dwc/pcie-designware.h +++ b/drivers/pci/controller/dwc/pcie-designware.h @@ -203,8 +203,8 @@ struct dw_pcie_rp { int msi_irq; struct irq_domain *irq_domain; struct irq_domain *msi_domain; - u16 msi_msg; dma_addr_t msi_data; + struct page *msi_page; struct irq_chip *msi_irq_chip; u32 num_vectors; u32 irq_mask[MAX_MSI_CTRLS]; |