From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: Re: [Patch RFC] ttm: nouveau accelerated on Xen pv-ops kernel Date: Thu, 25 Mar 2010 00:18:42 -0700 Message-ID: <4BAB0E52.5040604@goop.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Michael D Labriola Cc: Arvind R , Konrad Rzeszutek Wilk , xen-devel@lists.xensource.com, Joanna Rutkowska , xen-devel-bounces@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On 03/15/2010 07:44 AM, Michael D Labriola wrote: > xen-devel-bounces@lists.xensource.com wrote on 03/13/2010 05:03:22 PM: > > >> On 03/12/2010 01:45 PM, Arvind R wrote: >> >>> On Thu, Mar 11, 2010 at 4:32 PM, Pekka Paalanen wrote: >>> >>>> I'm adding dri-devel@ to CC, since this suggested patch touches >>>> TTM code, and none of the Nouveau code. TTM patches go via >>>> dri-devel@. >>>> >>>> Thanks. >>>> >>>> >>>> On Wed, 10 Mar 2010 18:51:21 +0530 >>>> Arvind R wrote: >>>> >>>> >>>>> Hi, >>>>> Following is a simple patch that is needed in nouveau to get >>>>> accelerated X on a Xen dom0 pv_ops kernel. The kernel is jeremy's >>>>> 2.6.31.6 as of 20100222. The whole gpu tree of nouveau (which is >>>>> almost the mainline merge), was substituted into the kernel-tree. >>>>> All components of X (mesa, Xorg-server-7.5, xf86-nouveau, libdrm) >>>>> used of the same day. >>>>> >>>>> Patch: >>>>> diff -Naur nouveau-kernel.orig/drivers/gpu/drm/ttm/ttm_bo_vm.c >>>>> nouveau-kernel.new/drivers/gpu/drm/ttm/ttm_bo_vm.c >>>>> --- nouveau-kernel.orig/drivers/gpu/drm/ttm/ttm_bo_vm.c 2010-01-27 >>>>> 10:19:28.000000000 +0530 >>>>> +++ nouveau-kernel.new/drivers/gpu/drm/ttm/ttm_bo_vm.c 2010-03-10 >>>>> 17:28:59.000000000 +0530 >>>>> @@ -271,7 +271,10 @@ >>>>> */ >>>>> >>>>> vma->vm_private_data = bo; >>>>> - vma->vm_flags |= VM_RESERVED | VM_IO | VM_MIXEDMAP | >>>>> VM_DONTEXPAND; >>>>> + vma->vm_flags |= VM_RESERVED | VM_MIXEDMAP | >>>>> VM_DONTEXPAND; >>>>> + if (!((bo->mem.placement& TTM_PL_MASK_MEM)& >>>>> TTM_PL_FLAG_TT)) >>>>> + vma->vm_flags |= VM_IO; >>>>> + vma->vm_page_prot = vma_get_vm_prot(vma->vm_flags); >>>>> return 0; >>>>> out_unref: >>>>> ttm_bo_unref(&bo); >>>>> >>>>> >>> sorry for the typo and other procedural errors. >>> the last added line should be >>> + vma->vm_page_prot = vm_get_page_prot(vma->vm_flags) >>> >>> >>>>> This patch is necessary because, in Xen, PFN of a page is >>>>> virtualised. So physical addresses >>>>> for DMA programming needs to use the MFN. Xen transparently does >>>>> the correct translation >>>>> using the _PAGE_IOMEM prot-bit in the PTE. If the bit is set, >>>>> then Xen assumes that the backing >>>>> memory is in the IOMEM space, and PFN equals MFN. If not set, >>>>> page_to_pfn() returns MFN. >>>>> >>>>> The patch enables the ttm_bo_vm_fault() handler to behave >>>>> correctly under Xen, and has no >>>>> side-effects on normal (not under Xen) operations. The use of >>>>> TTM_PL_FLAG_TT in the >>>>> check assumes that all other placements are backed by device >>>>> memory or IO. If there are >>>>> any other placements that use system memory, that flag has to be >>>>> OR'ed into the check. >>>>> >>>>> The above patch has no implications on a normal kernel or a Xen >>>>> pv_ops kernel booted without >>>>> the Xen hypervisor. My testing is on a debian-lenny environment >>>>> on a Core2 processor with >>>>> nVidia GeForce 9400 GT. >>>>> >>>> >>> Efficacy of patch: >>> successful flightgear run on dom0 AND bareboot! >>> >>> >> Jeremy, will you be merging this patch into any of the xen/stable-* >> branches any time soon? >> >> Thanks, >> joanna. >> > Hmm... I just verified that this patch fixes KMS/Nouveau issues in Xen on > my two primary test boxes (GeForce 6200, GeForce 7300). However, on my > really old machines (AGP GeForce2 MX200), this causes a new crash. These > old boxes were actually working fine in Xen prior to this patch, just > w/out 3d acceleration. Now I get the following messages in dmesg: > > [ 129.637319] [drm] nouveau 0000:01:00.0: Allocating FIFO number 1 > [ 129.638853] [drm] nouveau 0000:01:00.0: nouveau_channel_alloc: > initialised FIFO 1 > [ 129.643791] X: Corrupted page table at address 40412000 > [ 129.643815] *pdpt = 0000000015216001 *pde = 0000000000000000 > [ 129.643856] Bad pagetable: 000f [#1] SMP > [ 129.643897] last sysfs file: > /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/boot_vga > [ 129.643916] Modules linked in: bridge stp ipv6 autofs4 sunrpc raid1 > video output sbs sbshc pci_slot lp sg nouveau snd_intel8x0 snd_ac97_codec > ac97_bus snd_seq_dummy he atm ttm drm_kms_helper snd_seq_oss > snd_seq_midi_event sr_mod snd_seq cdrom drm serio_raw snd_seq_device > snd_pcm_oss snd_mixer_oss snd_pcm e100 mii i2c_algo_bit snd_timer > ata_generic snd pcspkr i2c_i801 i2c_core intel_rng soundcore i82860_edac > snd_page_alloc pata_acpi edac_core parport_pc floppy parport dm_snapshot > dm_zero dm_mirror dm_region_hash dm_log dm_mod raid0 ext3 mbcache jbd > aic7xxx scsi_transport_spi ata_piix libata sd_mod scsi_mod > [ 129.644024] > [ 129.644024] Pid: 3690, comm: X Not tainted (2.6.31.6-mdl5 #1) P4DC6 > [ 129.644024] EIP: 0073:[<40394596>] EFLAGS: 00210206 CPU: 0 > [ 129.644024] EIP is at 0x40394596 > [ 129.644024] EAX: 40412000 EBX: 40396cd8 ECX: 0909ee98 EDX: 00044000 > [ 129.644024] ESI: 00000034 EDI: 0909edd8 EBP: bfe7f798 ESP: bfe7f780 > [ 129.644024] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b > [ 129.644024] Process X (pid: 3690, ti=ea1ce000 task=ea77f110 > task.ti=ea1ce000) > [ 129.644024] > [ 129.644024] EIP: [<40394596>] 0x40394596 SS:ESP 007b:bfe7f780 > [ 129.644024] ---[ end trace 569eb18d737a8611 ]--- > [ 129.652216] [drm] nouveau 0000:01:00.0: nouveau_channel_free: freeing > fifo 1 > > > And my X log ends abruptly after this line: > (II) NOUVEAU(0): Opened GPU Channel 1 > > Any ideas? > BTW, what chipset does this machine have? Is it Intel? AMD? Other? J