# nvidia-kernel-patches

Source patches that make NVIDIA's driver build against kernels newer than the driver
knows about. Currently: **580.76.05 (kernel-open) on 7.0.14-11-pve** (Proxmox VE 9.2.10,
host `spicy`). New driver/kernel combos get their own patch + section as they happen.

Referenced from the house infra repo (trikilli → `hosts/spicy-rtx3090-bringup.md`),
which holds the full bring-up narrative (LXC passthrough, DKMS setup, device majors).
This repo is just the patch and how to use it.

## nvidia-580.76.05-kernel7.patch

Applies to the `kernel-open/` tree extracted from `NVIDIA-Linux-x86_64-580.76.05.run`.
Deployed on spicy 2026-08-10; DKMS source lives at `/usr/src/nvidia-580.76.05` on-host.

### Why the stock driver fails on kernel 7.x

Three independent causes:

1. **GCC 14 breaks NVIDIA's conftest.** The "is function X present" probes are
   *inverted*: they call X with no arguments and treat a successful compile (old
   compilers: implicit-declaration warning) as "absent". GCC 14 makes implicit
   declarations hard errors → every probe fails to compile → everything detected
   "present" → driver calls APIs that don't exist (and builds Tegra-only code on x86).
2. **Kernel 7.x headers need `-std=gnu11 -fms-extensions`.** kbuild passes these;
   conftest didn't. Without `-fms-extensions`, anonymous tagged-struct members
   (e.g. `struct filename { struct __filename_head; ... }`) silently drop and a
   `static_assert` on the struct size kills every probe including fs/device/pci headers.
3. **Real API changes** — table below.

### What the patch does

| File | Change |
|---|---|
| `conftest.sh` | Add `-std=gnu11 -fms-extensions -Wno-error=implicit-function-declaration -Wno-error=int-conversion -Wno-error=incompatible-pointer-types` to CFLAGS |
| `common/inc/nv-time.h`, `nvidia/os-interface.c` | `in_irq()` → `in_hardirq()` (removed) |
| `common/inc/nv-mm.h` | `vm_flags` writes → `vm_flags_set/clear()` / `vma_flags_set_word/clear_word()` (vm_flags is a const union member now) |
| `nvidia/nv-dma.c` | `dma_map_ops.map_resource` → `map_phys` (phys-addr DMA rework) |
| `nvidia/nv-pci.c` | `pci_resize_resource()` gained 4th arg `exclude_bars` → pass `0` |
| `nvidia-uvm/uvm_pmm_gpu.c` | `dev_pagemap_ops.page_free(page)` → `.folio_free(folio)` — thin wrappers added |
| `nvidia-uvm/uvm_hmm.c` | `zone_device_page_init(page)` → `(page, pgmap, order)` signature |

Use **kernel-open**, not the closed blob: GA102+ is fully supported, and the open
modules are `Dual MIT/GPL` so they can call the kernel's GPL-only VMA-lock API —
the closed blob reimplements those internals and chases a moving target.
Exclude `nvidia-drm` (DRM API churn, headless boxes don't need it) and `nvidia-peermem`.

### Apply + install

```sh
sh NVIDIA-Linux-x86_64-580.76.05.run --extract-only --target nv580
cd nv580 && patch -p1 < nvidia-580.76.05-kernel7.patch   # paths are kernel-open/...
cp -r kernel-open /usr/src/nvidia-580.76.05              # + dkms.conf: set version,
                                                          #   exclude nvidia-drm/peermem
dkms add nvidia/580.76.05 && dkms build nvidia/580.76.05 && dkms install nvidia/580.76.05
sh NVIDIA-Linux-x86_64-580.76.05.run --no-kernel-modules --silent --no-x-check  # userspace
```

Container userspace must match the host module version **exactly**; install inside
each LXC with `--no-kernel-modules`.

### Caveats

- Every kernel update re-runs the DKMS build against new headers — further API churn
  means further patching. Verify `nvidia-smi` (host, then containers) after any reboot.
- `-Wno-error=incompatible-pointer-types` in conftest is scoped to probe compiles only;
  the real module build keeps default warnings.