[PATCH] nouveau/firmware: using dma non-coherent interfaces for fw loading. (v2)

[Dave Airlie]

On Fri, 16 Aug 2024 at 10:53, Danilo Krummrich <dakr at kernel.org> wrote:
>
> On Fri, Aug 16, 2024 at 06:19:23AM +1000, Dave Airlie wrote:
> > From: Dave Airlie <airlied at redhat.com>
> >
> > Currently, enabling SG_DEBUG in the kernel will cause nouveau to hit a
> > BUG() on startup, when the iommu is enabled:
> >
> > kernel BUG at include/linux/scatterlist.h:187!
> > invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
> > CPU: 7 PID: 930 Comm: (udev-worker) Not tainted 6.9.0-rc3Lyude-Test+ #30
> > Hardware name: MSI MS-7A39/A320M GAMING PRO (MS-7A39), BIOS 1.I0 01/22/2019
> > RIP: 0010:sg_init_one+0x85/0xa0
> > Code: 69 88 32 01 83 e1 03 f6 c3 03 75 20 a8 01 75 1e 48 09 cb 41 89 54
> > 24 08 49 89 1c 24 41 89 6c 24 0c 5b 5d 41 5c e9 7b b9 88 00 <0f> 0b 0f 0b
> > 0f 0b 48 8b 05 5e 46 9a 01 eb b2 66 66 2e 0f 1f 84 00
> > RSP: 0018:ffffa776017bf6a0 EFLAGS: 00010246
> > RAX: 0000000000000000 RBX: ffffa77600d87000 RCX: 000000000000002b
> > RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffffa77680d87000
> > RBP: 000000000000e000 R08: 0000000000000000 R09: 0000000000000000
> > R10: ffff98f4c46aa508 R11: 0000000000000000 R12: ffff98f4c46aa508
> > R13: ffff98f4c46aa008 R14: ffffa77600d4a000 R15: ffffa77600d4a018
> > FS:  00007feeb5aae980(0000) GS:ffff98f5c4dc0000(0000) knlGS:0000000000000000
> > CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > CR2: 00007f22cb9a4520 CR3: 00000001043ba000 CR4: 00000000003506f0
> > Call Trace:
> >  <TASK>
> >  ? die+0x36/0x90
> >  ? do_trap+0xdd/0x100
> >  ? sg_init_one+0x85/0xa0
> >  ? do_error_trap+0x65/0x80
> >  ? sg_init_one+0x85/0xa0
> >  ? exc_invalid_op+0x50/0x70
> >  ? sg_init_one+0x85/0xa0
> >  ? asm_exc_invalid_op+0x1a/0x20
> >  ? sg_init_one+0x85/0xa0
> >  nvkm_firmware_ctor+0x14a/0x250 [nouveau]
> >  nvkm_falcon_fw_ctor+0x42/0x70 [nouveau]
> >  ga102_gsp_booter_ctor+0xb4/0x1a0 [nouveau]
> >  r535_gsp_oneinit+0xb3/0x15f0 [nouveau]
> >  ? srso_return_thunk+0x5/0x5f
> >  ? srso_return_thunk+0x5/0x5f
> >  ? nvkm_udevice_new+0x95/0x140 [nouveau]
> >  ? srso_return_thunk+0x5/0x5f
> >  ? srso_return_thunk+0x5/0x5f
> >  ? ktime_get+0x47/0xb0
> >
> > Fix this by using the non-coherent allocator instead, I think there
> > might be a better answer to this, but it involve ripping up some of
> > APIs using sg lists.
> >
> > v2: fix build warning
> >
> > Signed-off-by: Dave Airlie <airlied at redhat.com>
> > Cc: stable at vger.kernel.org
>
> Does this need the following fixes tag?
>
> Fixes: 2541626cfb79 ("drm/nouveau/acr: use common falcon HS FW code for ACR FWs")

Please add that on commit, it's probably not that necessary since I
expect prior to that things are just broken in a different place, but
probably good to have a backport target.

Dave.