From: Konrad Rzeszutek Wilk Date: Thu, 3 Dec 2009 15:31:57 +0000 (-0500) Subject: xen pvfb: Inhibit VM_IO flag to be set on vmalloc-ed framebuffers. X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=df11303c90406426847255ba498607f15a472a0a;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git xen pvfb: Inhibit VM_IO flag to be set on vmalloc-ed framebuffers. In Xen-paravirt mode, VM_IO flag signifies that the page frame number (PFN) is actually a machine frame number (MFN). This is correct for memory backed by PCI devices, but wrong for memory allocated from System RAM where the PFN != MFN. During page faults, pages with VM_IO, get assigned to special domain I/O domain and as said, the PFN is interpreted as MFN. When Xen hypervisor modifies the PTE it interprets the PFN as the MFN, complains and fails the PTE modification. The end result is an infinitive page fault in the domain. Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Jeremy Fitzhardinge --- diff --git a/drivers/video/xen-fbfront.c b/drivers/video/xen-fbfront.c index 54cd91610174..91a68e9eb66d 100644 --- a/drivers/video/xen-fbfront.c +++ b/drivers/video/xen-fbfront.c @@ -440,7 +440,7 @@ static int __devinit xenfb_probe(struct xenbus_device *dev, fb_info->fix.type = FB_TYPE_PACKED_PIXELS; fb_info->fix.accel = FB_ACCEL_NONE; - fb_info->flags = FBINFO_FLAG_DEFAULT; + fb_info->flags = FBINFO_FLAG_DEFAULT | FBINFO_VIRTFB; ret = fb_alloc_cmap(&fb_info->cmap, 256, 0); if (ret < 0) {