commit 9887bda0c831df0c044d6de147d002e48024fb4a upstream.
There's plenty of ways to fudge the GPU when developing on nouveau by
mistake, some of which can result in nouveau seriously spamming dmesg with
fault errors. This can be somewhat annoying, as it can quickly overrun the
message buffer (or your terminal emulator's buffer) and get rid of actually
useful feedback from the driver. While working on my new atomic only MST
branch, I ran into this issue a couple of times.
So, let's fix this by adding nvkm_error_ratelimited(), and using it to
ratelimit errors from faults. This should be fine for developers, since
it's nearly always only the first few faults that we care about seeing.
Plus, you can turn off rate limiting in the kernel if you really need to.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Karol Herbst <kherbst@redhat.com>
Cc: stable@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220429195350.85620-1-lyude@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We don't currently have any kind of real acceleration on Ampere GPUs,
but the TTM memcpy() fallback paths aren't really designed to handle
copies between different devices, such as on Optimus systems, and
result in a kernel OOPS.
A few options were investigated to try and fix this, but didn't work
out, and likely would have resulted in a very unpleasant experience
for users anyway.
This commit adds just enough support for setting up a single channel
connected to a copy engine, which the kernel can use to accelerate
the buffer copies between devices. Userspace has no access to this
incomplete channel support, but it's suitable for TTM's needs.
A more complete implementation of host(fifo) for Ampere GPUs is in
the works, but the required changes are far too invasive that they
would be unsuitable to backport to fix this issue on current kernels.
v2: fix GPFIFO length in RAMFC (reported by Karol)
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Karol Herbst <kherbst@redhat.com>
Cc: <stable@vger.kernel.org> # v5.12+
Reviewed-by: Karol Herbst <kherbst@redhat.com>
Tested-by: Karol Herbst <kherbst@redhat.com>
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210916220406.666454-1-skeggsb@gmail.com
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
No longer required now that userspace can't touch anything that might
need it, and should fix DRM MM operations racing with each other, and
the random hangs/crashes that come with that.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Long ago, there had been plans for making use of a bunch of these APIs
from userspace and there's various checks in place to stop misbehaving.
Countless other projects have occurred in the meantime, and the pieces
didn't finish falling into place for that to happen.
They will (hopefully) in the not-too-distant future, but it won't look
quite as insane. The super checks are causing problems right now, and
are going to be removed.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
I honestly don't even know why... These have never been used.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Some NVIDIA GPUs do not support direct atomic access to system memory via
PCIe. Instead this must be emulated by granting the GPU exclusive access
to the memory. This is achieved by replacing CPU page table entries with
special swap entries that fault on userspace access.
The driver then grants the GPU permission to update the page undergoing
atomic access via the GPU page tables. When CPU access to the page is
required a CPU fault is raised which calls into the device driver via MMU
notifiers to revoke the atomic access. The original page table entries
are then restored allowing CPU access to proceed.
Link: https://lkml.kernel.org/r/20210616105937.23201-11-apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Ben Skeggs <bskeggs@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This data is used to know which engines/classes are reachable on a given
channel's runlist, and needs to be replaced with something that doesn't
rely on subdev index.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
