From 8b794b141c633083408d0bfb2229b3406d0ebf99 Mon Sep 17 00:00:00 2001 From: Maciej Sosnowski Date: Thu, 26 Feb 2009 11:04:54 +0100 Subject: [PATCH] I/OAT: fail initialization on zero channels detection On some systems with I/OAT ver.2 when DCA is disabled in BIOS situations have been observed that zero DMA channels are detected instead of four. To avoid kernel panic driver should fail gracefully with appropriate message. Signed-off-by: Maciej Sosnowski Signed-off-by: Shannon Nelson Acked-by: Jeff Kirsher Signed-off-by: Dan Williams --- drivers/dma/ioat_dma.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/dma/ioat_dma.c b/drivers/dma/ioat_dma.c index 879f4a06e3ca..9012da7908f5 100644 --- a/drivers/dma/ioat_dma.c +++ b/drivers/dma/ioat_dma.c @@ -1659,6 +1659,13 @@ struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev, " %d channels, device version 0x%02x, driver version %s\n", device->common.chancnt, device->version, IOAT_DMA_VERSION); + if (!device->common.chancnt) { + dev_err(&device->pdev->dev, + "Intel(R) I/OAT DMA Engine problem found: " + "zero channels detected\n"); + goto err_setup_interrupts; + } + err = ioat_dma_setup_interrupts(device); if (err) goto err_setup_interrupts; -- 2.39.5