From 054bb7b215d621d7b3bba16f40bf3291ef4f430b Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Fri, 10 Feb 2017 17:40:29 +0000 Subject: [PATCH] target-arm: Declare virtio-mmio as dma-coherent in dt QEMU emulated hardware is always dma coherent with its guest. We do annotate that correctly on the PCI host controller, but left out virtio-mmio. Recent kernels have started to interpret that flag rather than take dma coherency as granted with virtio-mmio. While that is considered a kernel bug, as it breaks previously working systems, it showed that our dt description is incomplete. This patch adds the respective marker that allows guest OSs to evaluate that our virtio-mmio devices are indeed cache coherent. Signed-off-by: Alexander Graf Reviewed-by: Laszlo Ersek Reviewed-by: Ard Biesheuvel Message-id: 1486644810-33181-2-git-send-email-agraf@suse.de Signed-off-by: Peter Maydell --- hw/arm/vexpress.c | 1 + hw/arm/virt.c | 1 + 2 files changed, 2 insertions(+) diff --git a/hw/arm/vexpress.c b/hw/arm/vexpress.c index 58760f40ca..e05756846e 100644 --- a/hw/arm/vexpress.c +++ b/hw/arm/vexpress.c @@ -452,6 +452,7 @@ static int add_virtio_mmio_node(void *fdt, uint32_t acells, uint32_t scells, acells, addr, scells, size); qemu_fdt_setprop_cells(fdt, nodename, "interrupt-parent", intc); qemu_fdt_setprop_cells(fdt, nodename, "interrupts", 0, irq, 1); + qemu_fdt_setprop(fdt, nodename, "dma-coherent", NULL, 0); g_free(nodename); if (rc) { return -1; diff --git a/hw/arm/virt.c b/hw/arm/virt.c index 8eef143a5b..d20e627600 100644 --- a/hw/arm/virt.c +++ b/hw/arm/virt.c @@ -797,6 +797,7 @@ static void create_virtio_devices(const VirtMachineState *vms, qemu_irq *pic) qemu_fdt_setprop_cells(vms->fdt, nodename, "interrupts", GIC_FDT_IRQ_TYPE_SPI, irq, GIC_FDT_IRQ_FLAGS_EDGE_LO_HI); + qemu_fdt_setprop(vms->fdt, nodename, "dma-coherent", NULL, 0); g_free(nodename); } }