* [PATCH v2 1/5] drm/nova: use `zerocopy` in firmware.rs
2026-07-02 12:03 [RESEND PATCH v2 0/5] drm/nova: replace `transmute` with `zerocopy` Pedro Yudi Honda
@ 2026-07-02 12:03 ` Pedro Yudi Honda
2026-07-06 7:15 ` Alistair Popple
2026-07-02 12:03 ` [PATCH v2 2/5] drm/nova: use `zerocopy` in booter.rs Pedro Yudi Honda
` (4 subsequent siblings)
5 siblings, 1 reply; 13+ messages in thread
From: Pedro Yudi Honda @ 2026-07-02 12:03 UTC (permalink / raw)
To: dakr, acourbot, apopple
Cc: nico.antinori.7, aliceryhl, airlied, simona, dri-devel, ojeda,
rust-for-linux, nova-gpu, Pedro Yudi Honda
From: Pedro Yudi Honda <niyudi.honda@usp.br>
In firmware.rs, replace the following `transmute` traits with their
`zerocopy` equivalents:
- `transmute::FromBytes` -> `zerocopy::FromBytes`
Update call sites accordingly.
Note that the module `elf` is untouched, as the bindings generated by
bindgen do not implement `FromBytes` for the structs.
Signed-off-by: Pedro Yudi Honda <niyudi.honda@usp.br>
---
drivers/gpu/nova-core/firmware.rs | 10 +++-------
drivers/gpu/nova-core/firmware/fwsec/bootloader.rs | 4 +++-
2 files changed, 6 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/nova-core/firmware.rs b/drivers/gpu/nova-core/firmware.rs
index a94820a3b335..80ce0df244a8 100644
--- a/drivers/gpu/nova-core/firmware.rs
+++ b/drivers/gpu/nova-core/firmware.rs
@@ -11,8 +11,7 @@
device,
firmware,
prelude::*,
- str::CString,
- transmute::FromBytes, //
+ str::CString, //
};
use crate::{
@@ -347,7 +346,7 @@ fn no_patch_signature(self) -> FirmwareObject<F, Signed> {
/// Header common to most firmware files.
#[repr(C)]
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, FromBytes)]
struct BinHdr {
/// Magic number, must be `0x10de`.
bin_magic: u32,
@@ -363,9 +362,6 @@ struct BinHdr {
data_size: u32,
}
-// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
-unsafe impl FromBytes for BinHdr {}
-
// A firmware blob starting with a `BinHdr`.
struct BinFirmware<'a> {
hdr: BinHdr,
@@ -381,7 +377,7 @@ fn new(fw: &'a firmware::Firmware) -> Result<Self> {
fw.get(0..size_of::<BinHdr>())
// Extract header.
- .and_then(BinHdr::from_bytes_copy)
+ .and_then(|b| BinHdr::read_from_bytes(b).ok())
// Validate header.
.filter(|hdr| hdr.bin_magic == BIN_MAGIC)
.map(|hdr| Self { hdr, fw })
diff --git a/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs b/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
index d9fafd2eea5b..66b9f4d1b41c 100644
--- a/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
+++ b/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
@@ -25,6 +25,8 @@
},
};
+use zerocopy::FromBytes as _;
+
use crate::{
driver::Bar0,
falcon::{
@@ -150,7 +152,7 @@ pub(crate) fn new(
let hdr = fw
.data()
.get(0..size_of::<BinHdr>())
- .and_then(BinHdr::from_bytes_copy)
+ .and_then(|b| BinHdr::read_from_bytes(b).ok())
.ok_or(EINVAL)?;
let desc = {
--
2.34.1
^ permalink raw reply related [flat|nested] 13+ messages in thread* Re: [PATCH v2 1/5] drm/nova: use `zerocopy` in firmware.rs
2026-07-02 12:03 ` [PATCH v2 1/5] drm/nova: use `zerocopy` in firmware.rs Pedro Yudi Honda
@ 2026-07-06 7:15 ` Alistair Popple
0 siblings, 0 replies; 13+ messages in thread
From: Alistair Popple @ 2026-07-06 7:15 UTC (permalink / raw)
To: Pedro Yudi Honda
Cc: dakr, acourbot, nico.antinori.7, aliceryhl, airlied, simona,
dri-devel, ojeda, rust-for-linux, nova-gpu
On 2026-07-02 at 22:03 +1000, Pedro Yudi Honda <niyudi.honda@usp.br> wrote...
> From: Pedro Yudi Honda <niyudi.honda@usp.br>
>
> In firmware.rs, replace the following `transmute` traits with their
> `zerocopy` equivalents:
>
> - `transmute::FromBytes` -> `zerocopy::FromBytes`
>
> Update call sites accordingly.
>
> Note that the module `elf` is untouched, as the bindings generated by
> bindgen do not implement `FromBytes` for the structs.
Also I believe this module is pretty temporary and going to go away.
Everything here is pretty mechanical though, and looks good to me so:
Reviewed-by: Alistair Popple <apopple@nvidia.com>
> Signed-off-by: Pedro Yudi Honda <niyudi.honda@usp.br>
> ---
> drivers/gpu/nova-core/firmware.rs | 10 +++-------
> drivers/gpu/nova-core/firmware/fwsec/bootloader.rs | 4 +++-
> 2 files changed, 6 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/nova-core/firmware.rs b/drivers/gpu/nova-core/firmware.rs
> index a94820a3b335..80ce0df244a8 100644
> --- a/drivers/gpu/nova-core/firmware.rs
> +++ b/drivers/gpu/nova-core/firmware.rs
> @@ -11,8 +11,7 @@
> device,
> firmware,
> prelude::*,
> - str::CString,
> - transmute::FromBytes, //
> + str::CString, //
> };
>
> use crate::{
> @@ -347,7 +346,7 @@ fn no_patch_signature(self) -> FirmwareObject<F, Signed> {
>
> /// Header common to most firmware files.
> #[repr(C)]
> -#[derive(Debug, Clone)]
> +#[derive(Debug, Clone, FromBytes)]
> struct BinHdr {
> /// Magic number, must be `0x10de`.
> bin_magic: u32,
> @@ -363,9 +362,6 @@ struct BinHdr {
> data_size: u32,
> }
>
> -// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
> -unsafe impl FromBytes for BinHdr {}
> -
> // A firmware blob starting with a `BinHdr`.
> struct BinFirmware<'a> {
> hdr: BinHdr,
> @@ -381,7 +377,7 @@ fn new(fw: &'a firmware::Firmware) -> Result<Self> {
>
> fw.get(0..size_of::<BinHdr>())
> // Extract header.
> - .and_then(BinHdr::from_bytes_copy)
> + .and_then(|b| BinHdr::read_from_bytes(b).ok())
> // Validate header.
> .filter(|hdr| hdr.bin_magic == BIN_MAGIC)
> .map(|hdr| Self { hdr, fw })
> diff --git a/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs b/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
> index d9fafd2eea5b..66b9f4d1b41c 100644
> --- a/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
> +++ b/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
> @@ -25,6 +25,8 @@
> },
> };
>
> +use zerocopy::FromBytes as _;
> +
> use crate::{
> driver::Bar0,
> falcon::{
> @@ -150,7 +152,7 @@ pub(crate) fn new(
> let hdr = fw
> .data()
> .get(0..size_of::<BinHdr>())
> - .and_then(BinHdr::from_bytes_copy)
> + .and_then(|b| BinHdr::read_from_bytes(b).ok())
> .ok_or(EINVAL)?;
>
> let desc = {
> --
> 2.34.1
>
^ permalink raw reply [flat|nested] 13+ messages in thread
* [PATCH v2 2/5] drm/nova: use `zerocopy` in booter.rs
2026-07-02 12:03 [RESEND PATCH v2 0/5] drm/nova: replace `transmute` with `zerocopy` Pedro Yudi Honda
2026-07-02 12:03 ` [PATCH v2 1/5] drm/nova: use `zerocopy` in firmware.rs Pedro Yudi Honda
@ 2026-07-02 12:03 ` Pedro Yudi Honda
2026-07-06 11:39 ` Alistair Popple
2026-07-02 12:03 ` [PATCH v2 3/5] drm/nova: use `zerocopy` in fwsec.rs Pedro Yudi Honda
` (3 subsequent siblings)
5 siblings, 1 reply; 13+ messages in thread
From: Pedro Yudi Honda @ 2026-07-02 12:03 UTC (permalink / raw)
To: dakr, acourbot, apopple
Cc: nico.antinori.7, aliceryhl, airlied, simona, dri-devel, ojeda,
rust-for-linux, nova-gpu, Pedro Yudi Honda
From: Pedro Yudi Honda <niyudi.honda@usp.br>
In firmware/booter.rs, replace the following `transmute` traits with
their `zerocopy` equivalents:
- `transmute::FromBytes` -> `zerocopy::FromBytes`
Update call sites accordingly.
Signed-off-by: Pedro Yudi Honda <niyudi.honda@usp.br>
---
drivers/gpu/nova-core/firmware/booter.rs | 26 +++++++-----------------
1 file changed, 7 insertions(+), 19 deletions(-)
diff --git a/drivers/gpu/nova-core/firmware/booter.rs b/drivers/gpu/nova-core/firmware/booter.rs
index acb7f4d8a532..fe9389b84b90 100644
--- a/drivers/gpu/nova-core/firmware/booter.rs
+++ b/drivers/gpu/nova-core/firmware/booter.rs
@@ -10,8 +10,7 @@
use kernel::{
device,
dma::Coherent,
- prelude::*,
- transmute::FromBytes, //
+ prelude::*, //
};
use crate::{
@@ -43,7 +42,7 @@ fn frombytes_at<S: FromBytes + Sized>(slice: &[u8], offset: usize) -> Result<S>
let end = offset.checked_add(size_of::<S>()).ok_or(EINVAL)?;
slice
.get(offset..end)
- .and_then(S::from_bytes_copy)
+ .and_then(|b| S::read_from_bytes(b).ok())
.ok_or(EINVAL)
}
@@ -52,7 +51,7 @@ fn frombytes_at<S: FromBytes + Sized>(slice: &[u8], offset: usize) -> Result<S>
/// Such firmwares have an application-specific payload that needs to be patched with a given
/// signature.
#[repr(C)]
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, FromBytes)]
struct HsHeaderV2 {
/// Offset to the start of the signatures.
sig_prod_offset: u32,
@@ -75,9 +74,6 @@ struct HsHeaderV2 {
header_size: u32,
}
-// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
-unsafe impl FromBytes for HsHeaderV2 {}
-
/// Heavy-Secured Firmware image container.
///
/// This provides convenient access to the fields of [`HsHeaderV2`] that are actually indices to
@@ -144,6 +140,7 @@ fn signatures_iter(&'a self) -> Result<impl Iterator<Item = BooterSignature<'a>>
/// Signature parameters, as defined in the firmware.
#[repr(C)]
+#[derive(FromBytes)]
struct HsSignatureParams {
/// Fuse version to use.
fuse_ver: u32,
@@ -153,9 +150,6 @@ struct HsSignatureParams {
ucode_id: u32,
}
-// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
-unsafe impl FromBytes for HsSignatureParams {}
-
impl HsSignatureParams {
/// Returns the signature parameters contained in `hs_fw`.
///
@@ -170,14 +164,14 @@ fn new(hs_fw: &HsFirmwareV2<'_>) -> Result<Self> {
hs_fw
.fw
.get(start..end)
- .and_then(Self::from_bytes_copy)
+ .and_then(|b| Self::read_from_bytes(b).ok())
.ok_or(EINVAL)
}
}
/// Header for code and data load offsets.
#[repr(C)]
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, FromBytes)]
struct HsLoadHeaderV2 {
// Offset at which the code starts.
os_code_offset: u32,
@@ -191,9 +185,6 @@ struct HsLoadHeaderV2 {
num_apps: u32,
}
-// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
-unsafe impl FromBytes for HsLoadHeaderV2 {}
-
impl HsLoadHeaderV2 {
/// Returns the load header contained in `hs_fw`.
///
@@ -205,7 +196,7 @@ fn new(hs_fw: &HsFirmwareV2<'_>) -> Result<Self> {
/// Header for app code loader.
#[repr(C)]
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, FromBytes)]
struct HsLoadHeaderV2App {
/// Offset at which to load the app code.
offset: u32,
@@ -213,9 +204,6 @@ struct HsLoadHeaderV2App {
len: u32,
}
-// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
-unsafe impl FromBytes for HsLoadHeaderV2App {}
-
impl HsLoadHeaderV2App {
/// Returns the [`HsLoadHeaderV2App`] for app `idx` of `hs_fw`.
///
--
2.34.1
^ permalink raw reply related [flat|nested] 13+ messages in thread* Re: [PATCH v2 2/5] drm/nova: use `zerocopy` in booter.rs
2026-07-02 12:03 ` [PATCH v2 2/5] drm/nova: use `zerocopy` in booter.rs Pedro Yudi Honda
@ 2026-07-06 11:39 ` Alistair Popple
0 siblings, 0 replies; 13+ messages in thread
From: Alistair Popple @ 2026-07-06 11:39 UTC (permalink / raw)
To: Pedro Yudi Honda
Cc: dakr, acourbot, nico.antinori.7, aliceryhl, airlied, simona,
dri-devel, ojeda, rust-for-linux, nova-gpu
On 2026-07-02 at 22:03 +1000, Pedro Yudi Honda <niyudi.honda@usp.br> wrote...
> From: Pedro Yudi Honda <niyudi.honda@usp.br>
>
> In firmware/booter.rs, replace the following `transmute` traits with
> their `zerocopy` equivalents:
>
> - `transmute::FromBytes` -> `zerocopy::FromBytes`
Having a single item list reads a bit strange to me. I'd just say "replace
`transmute::FromBytes` with `zerocopy::FromBytes`" and if you want to list the
types it's replaced for you could. But that's a bit superfluous as it's clear
from the patch anyway.
But that's a small nit really, everything looks ok to me so feel free to add:
Reviewed-by: Alistair Popple <apopple@nvidia.com>
> Update call sites accordingly.
>
> Signed-off-by: Pedro Yudi Honda <niyudi.honda@usp.br>
> ---
> drivers/gpu/nova-core/firmware/booter.rs | 26 +++++++-----------------
> 1 file changed, 7 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/gpu/nova-core/firmware/booter.rs b/drivers/gpu/nova-core/firmware/booter.rs
> index acb7f4d8a532..fe9389b84b90 100644
> --- a/drivers/gpu/nova-core/firmware/booter.rs
> +++ b/drivers/gpu/nova-core/firmware/booter.rs
> @@ -10,8 +10,7 @@
> use kernel::{
> device,
> dma::Coherent,
> - prelude::*,
> - transmute::FromBytes, //
> + prelude::*, //
> };
>
> use crate::{
> @@ -43,7 +42,7 @@ fn frombytes_at<S: FromBytes + Sized>(slice: &[u8], offset: usize) -> Result<S>
> let end = offset.checked_add(size_of::<S>()).ok_or(EINVAL)?;
> slice
> .get(offset..end)
> - .and_then(S::from_bytes_copy)
> + .and_then(|b| S::read_from_bytes(b).ok())
> .ok_or(EINVAL)
> }
>
> @@ -52,7 +51,7 @@ fn frombytes_at<S: FromBytes + Sized>(slice: &[u8], offset: usize) -> Result<S>
> /// Such firmwares have an application-specific payload that needs to be patched with a given
> /// signature.
> #[repr(C)]
> -#[derive(Debug, Clone)]
> +#[derive(Debug, Clone, FromBytes)]
> struct HsHeaderV2 {
> /// Offset to the start of the signatures.
> sig_prod_offset: u32,
> @@ -75,9 +74,6 @@ struct HsHeaderV2 {
> header_size: u32,
> }
>
> -// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
> -unsafe impl FromBytes for HsHeaderV2 {}
> -
> /// Heavy-Secured Firmware image container.
> ///
> /// This provides convenient access to the fields of [`HsHeaderV2`] that are actually indices to
> @@ -144,6 +140,7 @@ fn signatures_iter(&'a self) -> Result<impl Iterator<Item = BooterSignature<'a>>
>
> /// Signature parameters, as defined in the firmware.
> #[repr(C)]
> +#[derive(FromBytes)]
> struct HsSignatureParams {
> /// Fuse version to use.
> fuse_ver: u32,
> @@ -153,9 +150,6 @@ struct HsSignatureParams {
> ucode_id: u32,
> }
>
> -// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
> -unsafe impl FromBytes for HsSignatureParams {}
> -
> impl HsSignatureParams {
> /// Returns the signature parameters contained in `hs_fw`.
> ///
> @@ -170,14 +164,14 @@ fn new(hs_fw: &HsFirmwareV2<'_>) -> Result<Self> {
> hs_fw
> .fw
> .get(start..end)
> - .and_then(Self::from_bytes_copy)
> + .and_then(|b| Self::read_from_bytes(b).ok())
> .ok_or(EINVAL)
> }
> }
>
> /// Header for code and data load offsets.
> #[repr(C)]
> -#[derive(Debug, Clone)]
> +#[derive(Debug, Clone, FromBytes)]
> struct HsLoadHeaderV2 {
> // Offset at which the code starts.
> os_code_offset: u32,
> @@ -191,9 +185,6 @@ struct HsLoadHeaderV2 {
> num_apps: u32,
> }
>
> -// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
> -unsafe impl FromBytes for HsLoadHeaderV2 {}
> -
> impl HsLoadHeaderV2 {
> /// Returns the load header contained in `hs_fw`.
> ///
> @@ -205,7 +196,7 @@ fn new(hs_fw: &HsFirmwareV2<'_>) -> Result<Self> {
>
> /// Header for app code loader.
> #[repr(C)]
> -#[derive(Debug, Clone)]
> +#[derive(Debug, Clone, FromBytes)]
> struct HsLoadHeaderV2App {
> /// Offset at which to load the app code.
> offset: u32,
> @@ -213,9 +204,6 @@ struct HsLoadHeaderV2App {
> len: u32,
> }
>
> -// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
> -unsafe impl FromBytes for HsLoadHeaderV2App {}
> -
> impl HsLoadHeaderV2App {
> /// Returns the [`HsLoadHeaderV2App`] for app `idx` of `hs_fw`.
> ///
> --
> 2.34.1
>
^ permalink raw reply [flat|nested] 13+ messages in thread
* [PATCH v2 3/5] drm/nova: use `zerocopy` in fwsec.rs
2026-07-02 12:03 [RESEND PATCH v2 0/5] drm/nova: replace `transmute` with `zerocopy` Pedro Yudi Honda
2026-07-02 12:03 ` [PATCH v2 1/5] drm/nova: use `zerocopy` in firmware.rs Pedro Yudi Honda
2026-07-02 12:03 ` [PATCH v2 2/5] drm/nova: use `zerocopy` in booter.rs Pedro Yudi Honda
@ 2026-07-02 12:03 ` Pedro Yudi Honda
2026-07-06 11:43 ` Alistair Popple
2026-07-02 12:03 ` [PATCH v2 4/5] drm/nova: use `zerocopy` in bootloader.rs Pedro Yudi Honda
` (2 subsequent siblings)
5 siblings, 1 reply; 13+ messages in thread
From: Pedro Yudi Honda @ 2026-07-02 12:03 UTC (permalink / raw)
To: dakr, acourbot, apopple
Cc: nico.antinori.7, aliceryhl, airlied, simona, dri-devel, ojeda,
rust-for-linux, nova-gpu, Pedro Yudi Honda
From: Pedro Yudi Honda <niyudi.honda@usp.br>
In firmware/fwsec.rs, replace the following `transmute` traits with
their `zerocopy` equivalents:
- `transmute::FromBytes` -> `zerocopy::FromBytes`
- `transmute::AsBytes` -> `zerocopy::IntoBytes`
- add `zerocopy::KnownLayout` where necessary
Update call sites accordingly.
Signed-off-by: Pedro Yudi Honda <niyudi.honda@usp.br>
---
drivers/gpu/nova-core/firmware/fwsec.rs | 49 ++++++-------------------
1 file changed, 12 insertions(+), 37 deletions(-)
diff --git a/drivers/gpu/nova-core/firmware/fwsec.rs b/drivers/gpu/nova-core/firmware/fwsec.rs
index 95e0dd77746b..1b75cdc02256 100644
--- a/drivers/gpu/nova-core/firmware/fwsec.rs
+++ b/drivers/gpu/nova-core/firmware/fwsec.rs
@@ -19,11 +19,7 @@
self,
Device, //
},
- prelude::*,
- transmute::{
- AsBytes,
- FromBytes, //
- },
+ prelude::*, //
};
use crate::{
@@ -49,26 +45,22 @@
const NVFW_FALCON_APPIF_ID_DMEMMAPPER: u32 = 0x4;
#[repr(C)]
-#[derive(Debug)]
+#[derive(Debug, FromBytes)]
struct FalconAppifHdrV1 {
version: u8,
header_size: u8,
entry_size: u8,
entry_count: u8,
}
-// SAFETY: Any byte sequence is valid for this struct.
-unsafe impl FromBytes for FalconAppifHdrV1 {}
#[repr(C, packed)]
-#[derive(Debug)]
+#[derive(Debug, FromBytes)]
struct FalconAppifV1 {
id: u32,
dmem_base: u32,
}
-// SAFETY: Any byte sequence is valid for this struct.
-unsafe impl FromBytes for FalconAppifV1 {}
-#[derive(Debug)]
+#[derive(Debug, FromBytes, IntoBytes, zerocopy_derive::KnownLayout)]
#[repr(C, packed)]
struct FalconAppifDmemmapperV3 {
signature: u32,
@@ -89,12 +81,8 @@ struct FalconAppifDmemmapperV3 {
ucode_cmd_mask1: u32,
multi_tgt_tbl: u32,
}
-// SAFETY: Any byte sequence is valid for this struct.
-unsafe impl FromBytes for FalconAppifDmemmapperV3 {}
-// SAFETY: This struct doesn't contain uninitialized bytes and doesn't have interior mutability.
-unsafe impl AsBytes for FalconAppifDmemmapperV3 {}
-#[derive(Debug)]
+#[derive(Debug, FromBytes, IntoBytes, zerocopy_derive::KnownLayout)]
#[repr(C, packed)]
struct ReadVbios {
ver: u32,
@@ -103,12 +91,8 @@ struct ReadVbios {
size: u32,
flags: u32,
}
-// SAFETY: Any byte sequence is valid for this struct.
-unsafe impl FromBytes for ReadVbios {}
-// SAFETY: This struct doesn't contain uninitialized bytes and doesn't have interior mutability.
-unsafe impl AsBytes for ReadVbios {}
-#[derive(Debug)]
+#[derive(Debug, FromBytes, IntoBytes, zerocopy_derive::KnownLayout)]
#[repr(C, packed)]
struct FrtsRegion {
ver: u32,
@@ -117,22 +101,15 @@ struct FrtsRegion {
size: u32,
ftype: u32,
}
-// SAFETY: Any byte sequence is valid for this struct.
-unsafe impl FromBytes for FrtsRegion {}
-// SAFETY: This struct doesn't contain uninitialized bytes and doesn't have interior mutability.
-unsafe impl AsBytes for FrtsRegion {}
const NVFW_FRTS_CMD_REGION_TYPE_FB: u32 = 2;
#[repr(C, packed)]
+#[derive(FromBytes, IntoBytes, zerocopy_derive::KnownLayout)]
struct FrtsCmd {
read_vbios: ReadVbios,
frts_region: FrtsRegion,
}
-// SAFETY: Any byte sequence is valid for this struct.
-unsafe impl FromBytes for FrtsCmd {}
-// SAFETY: This struct doesn't contain uninitialized bytes and doesn't have interior mutability.
-unsafe impl AsBytes for FrtsCmd {}
const NVFW_FALCON_APPIF_DMEMMAPPER_CMD_FRTS: u32 = 0x15;
const NVFW_FALCON_APPIF_DMEMMAPPER_CMD_SB: u32 = 0x19;
@@ -151,11 +128,9 @@ pub(crate) enum FwsecCommand {
/// A single signature that can be patched into a FWSEC image.
#[repr(transparent)]
+#[derive(FromBytes)]
pub(crate) struct Bcrt30Rsa3kSignature([u8; BCRT30_RSA3K_SIG_SIZE]);
-/// SAFETY: A signature is just an array of bytes.
-unsafe impl FromBytes for Bcrt30Rsa3kSignature {}
-
impl From<[u8; BCRT30_RSA3K_SIG_SIZE]> for Bcrt30Rsa3kSignature {
fn from(sig: [u8; BCRT30_RSA3K_SIG_SIZE]) -> Self {
Self(sig)
@@ -228,7 +203,7 @@ fn new_fwsec(bios: &Vbios, cmd: FwsecCommand) -> Result<Self> {
let hdr = ucode
.get(hdr_offset..)
- .and_then(FalconAppifHdrV1::from_bytes_prefix)
+ .and_then(|b| FalconAppifHdrV1::read_from_prefix(b).ok())
.ok_or(EINVAL)?
.0;
@@ -246,7 +221,7 @@ fn new_fwsec(bios: &Vbios, cmd: FwsecCommand) -> Result<Self> {
let app = ucode
.get(entry_offset..)
- .and_then(FalconAppifV1::from_bytes_prefix)
+ .and_then(|b| FalconAppifV1::read_from_prefix(b).ok())
.ok_or(EINVAL)?
.0;
@@ -263,7 +238,7 @@ fn new_fwsec(bios: &Vbios, cmd: FwsecCommand) -> Result<Self> {
let dmem_mapper = ucode
.get_mut(dmem_mapper_offset..)
- .and_then(FalconAppifDmemmapperV3::from_bytes_mut_prefix)
+ .and_then(|b| FalconAppifDmemmapperV3::mut_from_prefix(b).ok())
.ok_or(EINVAL)?
.0;
@@ -281,7 +256,7 @@ fn new_fwsec(bios: &Vbios, cmd: FwsecCommand) -> Result<Self> {
let frts_cmd = ucode
.get_mut(frts_cmd_offset..)
- .and_then(FrtsCmd::from_bytes_mut_prefix)
+ .and_then(|b| FrtsCmd::mut_from_prefix(b).ok())
.ok_or(EINVAL)?
.0;
--
2.34.1
^ permalink raw reply related [flat|nested] 13+ messages in thread* Re: [PATCH v2 3/5] drm/nova: use `zerocopy` in fwsec.rs
2026-07-02 12:03 ` [PATCH v2 3/5] drm/nova: use `zerocopy` in fwsec.rs Pedro Yudi Honda
@ 2026-07-06 11:43 ` Alistair Popple
0 siblings, 0 replies; 13+ messages in thread
From: Alistair Popple @ 2026-07-06 11:43 UTC (permalink / raw)
To: Pedro Yudi Honda
Cc: dakr, acourbot, nico.antinori.7, aliceryhl, airlied, simona,
dri-devel, ojeda, rust-for-linux, nova-gpu
On 2026-07-02 at 22:03 +1000, Pedro Yudi Honda <niyudi.honda@usp.br> wrote...
> From: Pedro Yudi Honda <niyudi.honda@usp.br>
>
> In firmware/fwsec.rs, replace the following `transmute` traits with
> their `zerocopy` equivalents:
>
> - `transmute::FromBytes` -> `zerocopy::FromBytes`
> - `transmute::AsBytes` -> `zerocopy::IntoBytes`
> - add `zerocopy::KnownLayout` where necessary
Argh, ok. It makes more sense when there are more things in the list :-) That
said I'd also be ok without, but either is fine.
Reviewed-by: Alistair Popple <apopple@nvidia.com>
> Update call sites accordingly.
>
> Signed-off-by: Pedro Yudi Honda <niyudi.honda@usp.br>
> ---
> drivers/gpu/nova-core/firmware/fwsec.rs | 49 ++++++-------------------
> 1 file changed, 12 insertions(+), 37 deletions(-)
>
> diff --git a/drivers/gpu/nova-core/firmware/fwsec.rs b/drivers/gpu/nova-core/firmware/fwsec.rs
> index 95e0dd77746b..1b75cdc02256 100644
> --- a/drivers/gpu/nova-core/firmware/fwsec.rs
> +++ b/drivers/gpu/nova-core/firmware/fwsec.rs
> @@ -19,11 +19,7 @@
> self,
> Device, //
> },
> - prelude::*,
> - transmute::{
> - AsBytes,
> - FromBytes, //
> - },
> + prelude::*, //
> };
>
> use crate::{
> @@ -49,26 +45,22 @@
> const NVFW_FALCON_APPIF_ID_DMEMMAPPER: u32 = 0x4;
>
> #[repr(C)]
> -#[derive(Debug)]
> +#[derive(Debug, FromBytes)]
> struct FalconAppifHdrV1 {
> version: u8,
> header_size: u8,
> entry_size: u8,
> entry_count: u8,
> }
> -// SAFETY: Any byte sequence is valid for this struct.
> -unsafe impl FromBytes for FalconAppifHdrV1 {}
>
> #[repr(C, packed)]
> -#[derive(Debug)]
> +#[derive(Debug, FromBytes)]
> struct FalconAppifV1 {
> id: u32,
> dmem_base: u32,
> }
> -// SAFETY: Any byte sequence is valid for this struct.
> -unsafe impl FromBytes for FalconAppifV1 {}
>
> -#[derive(Debug)]
> +#[derive(Debug, FromBytes, IntoBytes, zerocopy_derive::KnownLayout)]
> #[repr(C, packed)]
> struct FalconAppifDmemmapperV3 {
> signature: u32,
> @@ -89,12 +81,8 @@ struct FalconAppifDmemmapperV3 {
> ucode_cmd_mask1: u32,
> multi_tgt_tbl: u32,
> }
> -// SAFETY: Any byte sequence is valid for this struct.
> -unsafe impl FromBytes for FalconAppifDmemmapperV3 {}
> -// SAFETY: This struct doesn't contain uninitialized bytes and doesn't have interior mutability.
> -unsafe impl AsBytes for FalconAppifDmemmapperV3 {}
>
> -#[derive(Debug)]
> +#[derive(Debug, FromBytes, IntoBytes, zerocopy_derive::KnownLayout)]
> #[repr(C, packed)]
> struct ReadVbios {
> ver: u32,
> @@ -103,12 +91,8 @@ struct ReadVbios {
> size: u32,
> flags: u32,
> }
> -// SAFETY: Any byte sequence is valid for this struct.
> -unsafe impl FromBytes for ReadVbios {}
> -// SAFETY: This struct doesn't contain uninitialized bytes and doesn't have interior mutability.
> -unsafe impl AsBytes for ReadVbios {}
>
> -#[derive(Debug)]
> +#[derive(Debug, FromBytes, IntoBytes, zerocopy_derive::KnownLayout)]
> #[repr(C, packed)]
> struct FrtsRegion {
> ver: u32,
> @@ -117,22 +101,15 @@ struct FrtsRegion {
> size: u32,
> ftype: u32,
> }
> -// SAFETY: Any byte sequence is valid for this struct.
> -unsafe impl FromBytes for FrtsRegion {}
> -// SAFETY: This struct doesn't contain uninitialized bytes and doesn't have interior mutability.
> -unsafe impl AsBytes for FrtsRegion {}
>
> const NVFW_FRTS_CMD_REGION_TYPE_FB: u32 = 2;
>
> #[repr(C, packed)]
> +#[derive(FromBytes, IntoBytes, zerocopy_derive::KnownLayout)]
> struct FrtsCmd {
> read_vbios: ReadVbios,
> frts_region: FrtsRegion,
> }
> -// SAFETY: Any byte sequence is valid for this struct.
> -unsafe impl FromBytes for FrtsCmd {}
> -// SAFETY: This struct doesn't contain uninitialized bytes and doesn't have interior mutability.
> -unsafe impl AsBytes for FrtsCmd {}
>
> const NVFW_FALCON_APPIF_DMEMMAPPER_CMD_FRTS: u32 = 0x15;
> const NVFW_FALCON_APPIF_DMEMMAPPER_CMD_SB: u32 = 0x19;
> @@ -151,11 +128,9 @@ pub(crate) enum FwsecCommand {
>
> /// A single signature that can be patched into a FWSEC image.
> #[repr(transparent)]
> +#[derive(FromBytes)]
> pub(crate) struct Bcrt30Rsa3kSignature([u8; BCRT30_RSA3K_SIG_SIZE]);
>
> -/// SAFETY: A signature is just an array of bytes.
> -unsafe impl FromBytes for Bcrt30Rsa3kSignature {}
> -
> impl From<[u8; BCRT30_RSA3K_SIG_SIZE]> for Bcrt30Rsa3kSignature {
> fn from(sig: [u8; BCRT30_RSA3K_SIG_SIZE]) -> Self {
> Self(sig)
> @@ -228,7 +203,7 @@ fn new_fwsec(bios: &Vbios, cmd: FwsecCommand) -> Result<Self> {
>
> let hdr = ucode
> .get(hdr_offset..)
> - .and_then(FalconAppifHdrV1::from_bytes_prefix)
> + .and_then(|b| FalconAppifHdrV1::read_from_prefix(b).ok())
> .ok_or(EINVAL)?
> .0;
>
> @@ -246,7 +221,7 @@ fn new_fwsec(bios: &Vbios, cmd: FwsecCommand) -> Result<Self> {
>
> let app = ucode
> .get(entry_offset..)
> - .and_then(FalconAppifV1::from_bytes_prefix)
> + .and_then(|b| FalconAppifV1::read_from_prefix(b).ok())
> .ok_or(EINVAL)?
> .0;
>
> @@ -263,7 +238,7 @@ fn new_fwsec(bios: &Vbios, cmd: FwsecCommand) -> Result<Self> {
>
> let dmem_mapper = ucode
> .get_mut(dmem_mapper_offset..)
> - .and_then(FalconAppifDmemmapperV3::from_bytes_mut_prefix)
> + .and_then(|b| FalconAppifDmemmapperV3::mut_from_prefix(b).ok())
> .ok_or(EINVAL)?
> .0;
>
> @@ -281,7 +256,7 @@ fn new_fwsec(bios: &Vbios, cmd: FwsecCommand) -> Result<Self> {
>
> let frts_cmd = ucode
> .get_mut(frts_cmd_offset..)
> - .and_then(FrtsCmd::from_bytes_mut_prefix)
> + .and_then(|b| FrtsCmd::mut_from_prefix(b).ok())
> .ok_or(EINVAL)?
> .0;
>
> --
> 2.34.1
>
^ permalink raw reply [flat|nested] 13+ messages in thread
* [PATCH v2 4/5] drm/nova: use `zerocopy` in bootloader.rs
2026-07-02 12:03 [RESEND PATCH v2 0/5] drm/nova: replace `transmute` with `zerocopy` Pedro Yudi Honda
` (2 preceding siblings ...)
2026-07-02 12:03 ` [PATCH v2 3/5] drm/nova: use `zerocopy` in fwsec.rs Pedro Yudi Honda
@ 2026-07-02 12:03 ` Pedro Yudi Honda
2026-07-06 11:44 ` Alistair Popple
2026-07-02 12:03 ` [PATCH v2 5/5] drm/nova: use `zerocopy` in riscv.rs Pedro Yudi Honda
2026-07-04 13:00 ` [RESEND PATCH v2 0/5] drm/nova: replace `transmute` with `zerocopy` Miguel Ojeda
5 siblings, 1 reply; 13+ messages in thread
From: Pedro Yudi Honda @ 2026-07-02 12:03 UTC (permalink / raw)
To: dakr, acourbot, apopple
Cc: nico.antinori.7, aliceryhl, airlied, simona, dri-devel, ojeda,
rust-for-linux, nova-gpu, Pedro Yudi Honda
From: Pedro Yudi Honda <niyudi.honda@usp.br>
In firmware/fwsec/bootloader.rs, replace the following `transmute`
traits with their `zerocopy` equivalents:
- `transmute::FromBytes` -> `zerocopy::FromBytes`
- `transmute::AsBytes` -> `zerocopy::IntoBytes`
- add `zerocopy::Immutable` where necessary
Update call sites accordingly.
Signed-off-by: Pedro Yudi Honda <niyudi.honda@usp.br>
---
.../gpu/nova-core/firmware/fwsec/bootloader.rs | 18 ++++--------------
1 file changed, 4 insertions(+), 14 deletions(-)
diff --git a/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs b/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
index 66b9f4d1b41c..03d3090bd9ef 100644
--- a/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
+++ b/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
@@ -18,15 +18,9 @@
Alignable,
Alignment, //
},
- sizes,
- transmute::{
- AsBytes,
- FromBytes, //
- },
+ sizes, //
};
-use zerocopy::FromBytes as _;
-
use crate::{
driver::Bar0,
falcon::{
@@ -57,7 +51,7 @@
///
/// Most of its fields appear to be legacy and carry incorrect values, so they are left unused.
#[repr(C)]
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, FromBytes)]
struct BootloaderDesc {
/// Starting tag of bootloader.
start_tag: u32,
@@ -73,15 +67,13 @@ struct BootloaderDesc {
/// Size of data section in the image. Unused as we build the data section ourselves.
_data_size: u32,
}
-// SAFETY: any byte sequence is valid for this struct.
-unsafe impl FromBytes for BootloaderDesc {}
/// Structure used by the boot-loader to load the rest of the code.
///
/// This has to be filled by the GPU driver and copied into DMEM at offset
/// [`BootloaderDesc.dmem_load_off`].
#[repr(C, packed)]
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, IntoBytes, zerocopy_derive::Immutable)]
struct BootloaderDmemDescV2 {
/// Reserved, should always be first element.
reserved: [u32; 4],
@@ -120,8 +112,6 @@ struct BootloaderDmemDescV2 {
/// Arguments to be passed to the target firmware being loaded.
argv: u32,
}
-// SAFETY: This struct doesn't contain uninitialized bytes and doesn't have interior mutability.
-unsafe impl AsBytes for BootloaderDmemDescV2 {}
/// Wrapper for [`FwsecFirmware`] that includes the bootloader performing the actual load
/// operation.
@@ -160,7 +150,7 @@ pub(crate) fn new(
fw.data()
.get(desc_offset..)
- .and_then(BootloaderDesc::from_bytes_copy_prefix)
+ .and_then(|b| BootloaderDesc::read_from_prefix(b).ok())
.ok_or(EINVAL)?
.0
};
--
2.34.1
^ permalink raw reply related [flat|nested] 13+ messages in thread* Re: [PATCH v2 4/5] drm/nova: use `zerocopy` in bootloader.rs
2026-07-02 12:03 ` [PATCH v2 4/5] drm/nova: use `zerocopy` in bootloader.rs Pedro Yudi Honda
@ 2026-07-06 11:44 ` Alistair Popple
0 siblings, 0 replies; 13+ messages in thread
From: Alistair Popple @ 2026-07-06 11:44 UTC (permalink / raw)
To: Pedro Yudi Honda
Cc: dakr, acourbot, nico.antinori.7, aliceryhl, airlied, simona,
dri-devel, ojeda, rust-for-linux, nova-gpu
On 2026-07-02 at 22:03 +1000, Pedro Yudi Honda <niyudi.honda@usp.br> wrote...
> From: Pedro Yudi Honda <niyudi.honda@usp.br>
>
> In firmware/fwsec/bootloader.rs, replace the following `transmute`
> traits with their `zerocopy` equivalents:
>
> - `transmute::FromBytes` -> `zerocopy::FromBytes`
> - `transmute::AsBytes` -> `zerocopy::IntoBytes`
> - add `zerocopy::Immutable` where necessary
>
> Update call sites accordingly.
Reviewed-by: Alistair Popple <apopple@nvidia.com>
>
> Signed-off-by: Pedro Yudi Honda <niyudi.honda@usp.br>
> ---
> .../gpu/nova-core/firmware/fwsec/bootloader.rs | 18 ++++--------------
> 1 file changed, 4 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs b/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
> index 66b9f4d1b41c..03d3090bd9ef 100644
> --- a/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
> +++ b/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
> @@ -18,15 +18,9 @@
> Alignable,
> Alignment, //
> },
> - sizes,
> - transmute::{
> - AsBytes,
> - FromBytes, //
> - },
> + sizes, //
> };
>
> -use zerocopy::FromBytes as _;
> -
> use crate::{
> driver::Bar0,
> falcon::{
> @@ -57,7 +51,7 @@
> ///
> /// Most of its fields appear to be legacy and carry incorrect values, so they are left unused.
> #[repr(C)]
> -#[derive(Debug, Clone)]
> +#[derive(Debug, Clone, FromBytes)]
> struct BootloaderDesc {
> /// Starting tag of bootloader.
> start_tag: u32,
> @@ -73,15 +67,13 @@ struct BootloaderDesc {
> /// Size of data section in the image. Unused as we build the data section ourselves.
> _data_size: u32,
> }
> -// SAFETY: any byte sequence is valid for this struct.
> -unsafe impl FromBytes for BootloaderDesc {}
>
> /// Structure used by the boot-loader to load the rest of the code.
> ///
> /// This has to be filled by the GPU driver and copied into DMEM at offset
> /// [`BootloaderDesc.dmem_load_off`].
> #[repr(C, packed)]
> -#[derive(Debug, Clone)]
> +#[derive(Debug, Clone, IntoBytes, zerocopy_derive::Immutable)]
> struct BootloaderDmemDescV2 {
> /// Reserved, should always be first element.
> reserved: [u32; 4],
> @@ -120,8 +112,6 @@ struct BootloaderDmemDescV2 {
> /// Arguments to be passed to the target firmware being loaded.
> argv: u32,
> }
> -// SAFETY: This struct doesn't contain uninitialized bytes and doesn't have interior mutability.
> -unsafe impl AsBytes for BootloaderDmemDescV2 {}
>
> /// Wrapper for [`FwsecFirmware`] that includes the bootloader performing the actual load
> /// operation.
> @@ -160,7 +150,7 @@ pub(crate) fn new(
>
> fw.data()
> .get(desc_offset..)
> - .and_then(BootloaderDesc::from_bytes_copy_prefix)
> + .and_then(|b| BootloaderDesc::read_from_prefix(b).ok())
> .ok_or(EINVAL)?
> .0
> };
> --
> 2.34.1
>
^ permalink raw reply [flat|nested] 13+ messages in thread
* [PATCH v2 5/5] drm/nova: use `zerocopy` in riscv.rs
2026-07-02 12:03 [RESEND PATCH v2 0/5] drm/nova: replace `transmute` with `zerocopy` Pedro Yudi Honda
` (3 preceding siblings ...)
2026-07-02 12:03 ` [PATCH v2 4/5] drm/nova: use `zerocopy` in bootloader.rs Pedro Yudi Honda
@ 2026-07-02 12:03 ` Pedro Yudi Honda
2026-07-06 11:44 ` Alistair Popple
2026-07-04 13:00 ` [RESEND PATCH v2 0/5] drm/nova: replace `transmute` with `zerocopy` Miguel Ojeda
5 siblings, 1 reply; 13+ messages in thread
From: Pedro Yudi Honda @ 2026-07-02 12:03 UTC (permalink / raw)
To: dakr, acourbot, apopple
Cc: nico.antinori.7, aliceryhl, airlied, simona, dri-devel, ojeda,
rust-for-linux, nova-gpu, Pedro Yudi Honda
From: Pedro Yudi Honda <niyudi.honda@usp.br>
In riscv.rs, replave the following `transmute` traits with their
`zerocopy` equivalents:
- `transmute::FromBytes` -> `zerocopy::FromBytes`
Update call sites accordingly.
Signed-off-by: Pedro Yudi Honda <niyudi.honda@usp.br>
---
drivers/gpu/nova-core/firmware/riscv.rs | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/nova-core/firmware/riscv.rs b/drivers/gpu/nova-core/firmware/riscv.rs
index 2afa7f36404e..ba56bc7d4188 100644
--- a/drivers/gpu/nova-core/firmware/riscv.rs
+++ b/drivers/gpu/nova-core/firmware/riscv.rs
@@ -7,8 +7,7 @@
device,
dma::Coherent,
firmware::Firmware,
- prelude::*,
- transmute::FromBytes, //
+ prelude::*, //
};
use crate::{
@@ -18,7 +17,7 @@
/// Descriptor for microcode running on a RISC-V core.
#[repr(C)]
-#[derive(Debug)]
+#[derive(Debug, FromBytes)]
struct RmRiscvUCodeDesc {
version: u32,
bootloader_offset: u32,
@@ -36,9 +35,6 @@ struct RmRiscvUCodeDesc {
monitor_code_size: u32,
}
-// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
-unsafe impl FromBytes for RmRiscvUCodeDesc {}
-
impl RmRiscvUCodeDesc {
/// Interprets the header of `bin_fw` as a [`RmRiscvUCodeDesc`] and returns it.
///
@@ -50,7 +46,7 @@ fn new(bin_fw: &BinFirmware<'_>) -> Result<Self> {
bin_fw
.fw
.get(offset..end)
- .and_then(Self::from_bytes_copy)
+ .and_then(|b| Self::read_from_bytes(b).ok())
.ok_or(EINVAL)
}
}
--
2.34.1
^ permalink raw reply related [flat|nested] 13+ messages in thread* Re: [PATCH v2 5/5] drm/nova: use `zerocopy` in riscv.rs
2026-07-02 12:03 ` [PATCH v2 5/5] drm/nova: use `zerocopy` in riscv.rs Pedro Yudi Honda
@ 2026-07-06 11:44 ` Alistair Popple
0 siblings, 0 replies; 13+ messages in thread
From: Alistair Popple @ 2026-07-06 11:44 UTC (permalink / raw)
To: Pedro Yudi Honda
Cc: dakr, acourbot, nico.antinori.7, aliceryhl, airlied, simona,
dri-devel, ojeda, rust-for-linux, nova-gpu
On 2026-07-02 at 22:03 +1000, Pedro Yudi Honda <niyudi.honda@usp.br> wrote...
> From: Pedro Yudi Honda <niyudi.honda@usp.br>
>
> In riscv.rs, replave the following `transmute` traits with their
> `zerocopy` equivalents:
>
> - `transmute::FromBytes` -> `zerocopy::FromBytes`
>
> Update call sites accordingly.
Thanks for the clean-ups.
Reviewed-by: Alistair Popple <apopple@nvidia.com>
> Signed-off-by: Pedro Yudi Honda <niyudi.honda@usp.br>
> ---
> drivers/gpu/nova-core/firmware/riscv.rs | 10 +++-------
> 1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/nova-core/firmware/riscv.rs b/drivers/gpu/nova-core/firmware/riscv.rs
> index 2afa7f36404e..ba56bc7d4188 100644
> --- a/drivers/gpu/nova-core/firmware/riscv.rs
> +++ b/drivers/gpu/nova-core/firmware/riscv.rs
> @@ -7,8 +7,7 @@
> device,
> dma::Coherent,
> firmware::Firmware,
> - prelude::*,
> - transmute::FromBytes, //
> + prelude::*, //
> };
>
> use crate::{
> @@ -18,7 +17,7 @@
>
> /// Descriptor for microcode running on a RISC-V core.
> #[repr(C)]
> -#[derive(Debug)]
> +#[derive(Debug, FromBytes)]
> struct RmRiscvUCodeDesc {
> version: u32,
> bootloader_offset: u32,
> @@ -36,9 +35,6 @@ struct RmRiscvUCodeDesc {
> monitor_code_size: u32,
> }
>
> -// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
> -unsafe impl FromBytes for RmRiscvUCodeDesc {}
> -
> impl RmRiscvUCodeDesc {
> /// Interprets the header of `bin_fw` as a [`RmRiscvUCodeDesc`] and returns it.
> ///
> @@ -50,7 +46,7 @@ fn new(bin_fw: &BinFirmware<'_>) -> Result<Self> {
> bin_fw
> .fw
> .get(offset..end)
> - .and_then(Self::from_bytes_copy)
> + .and_then(|b| Self::read_from_bytes(b).ok())
> .ok_or(EINVAL)
> }
> }
> --
> 2.34.1
>
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [RESEND PATCH v2 0/5] drm/nova: replace `transmute` with `zerocopy`
2026-07-02 12:03 [RESEND PATCH v2 0/5] drm/nova: replace `transmute` with `zerocopy` Pedro Yudi Honda
` (4 preceding siblings ...)
2026-07-02 12:03 ` [PATCH v2 5/5] drm/nova: use `zerocopy` in riscv.rs Pedro Yudi Honda
@ 2026-07-04 13:00 ` Miguel Ojeda
5 siblings, 0 replies; 13+ messages in thread
From: Miguel Ojeda @ 2026-07-04 13:00 UTC (permalink / raw)
To: Pedro Yudi Honda
Cc: dakr, acourbot, apopple, nico.antinori.7, aliceryhl, airlied,
simona, dri-devel, ojeda, rust-for-linux, nova-gpu
On Thu, Jul 2, 2026 at 2:05 PM Pedro Yudi Honda <niyudi.honda@usp.br> wrote:
>
> Resent because of wrong target list and wrong email in "From:".
It is good that you mention this, thanks!
For future series, please also include a changelog between versions,
i.e. so that reviewers know what changed :)
Cheers,
Miguel
^ permalink raw reply [flat|nested] 13+ messages in thread
* [PATCH v2 2/5] drm/nova: use `zerocopy` in booter.rs
2026-07-01 17:40 [PATCH " Pedro Yudi Honda
@ 2026-07-01 17:40 ` Pedro Yudi Honda
0 siblings, 0 replies; 13+ messages in thread
From: Pedro Yudi Honda @ 2026-07-01 17:40 UTC (permalink / raw)
To: dakr, acourbot, apopple
Cc: nico.antinori.7, aliceryhl, airlied, simona, dri-devel, ojeda,
rust-for-linux, Pedro Yudi Honda
From: Pedro Yudi Honda <niyudi.honda@usp.br>
In firmware/booter.rs, replace the following `transmute` traits with
their `zerocopy` equivalents:
- `transmute::FromBytes` -> `zerocopy::FromBytes`
Update call sites accordingly.
Signed-off-by: Pedro Yudi Honda <niyudi.honda@usp.br>
---
drivers/gpu/nova-core/firmware/booter.rs | 26 +++++++-----------------
1 file changed, 7 insertions(+), 19 deletions(-)
diff --git a/drivers/gpu/nova-core/firmware/booter.rs b/drivers/gpu/nova-core/firmware/booter.rs
index acb7f4d8a532..fe9389b84b90 100644
--- a/drivers/gpu/nova-core/firmware/booter.rs
+++ b/drivers/gpu/nova-core/firmware/booter.rs
@@ -10,8 +10,7 @@
use kernel::{
device,
dma::Coherent,
- prelude::*,
- transmute::FromBytes, //
+ prelude::*, //
};
use crate::{
@@ -43,7 +42,7 @@ fn frombytes_at<S: FromBytes + Sized>(slice: &[u8], offset: usize) -> Result<S>
let end = offset.checked_add(size_of::<S>()).ok_or(EINVAL)?;
slice
.get(offset..end)
- .and_then(S::from_bytes_copy)
+ .and_then(|b| S::read_from_bytes(b).ok())
.ok_or(EINVAL)
}
@@ -52,7 +51,7 @@ fn frombytes_at<S: FromBytes + Sized>(slice: &[u8], offset: usize) -> Result<S>
/// Such firmwares have an application-specific payload that needs to be patched with a given
/// signature.
#[repr(C)]
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, FromBytes)]
struct HsHeaderV2 {
/// Offset to the start of the signatures.
sig_prod_offset: u32,
@@ -75,9 +74,6 @@ struct HsHeaderV2 {
header_size: u32,
}
-// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
-unsafe impl FromBytes for HsHeaderV2 {}
-
/// Heavy-Secured Firmware image container.
///
/// This provides convenient access to the fields of [`HsHeaderV2`] that are actually indices to
@@ -144,6 +140,7 @@ fn signatures_iter(&'a self) -> Result<impl Iterator<Item = BooterSignature<'a>>
/// Signature parameters, as defined in the firmware.
#[repr(C)]
+#[derive(FromBytes)]
struct HsSignatureParams {
/// Fuse version to use.
fuse_ver: u32,
@@ -153,9 +150,6 @@ struct HsSignatureParams {
ucode_id: u32,
}
-// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
-unsafe impl FromBytes for HsSignatureParams {}
-
impl HsSignatureParams {
/// Returns the signature parameters contained in `hs_fw`.
///
@@ -170,14 +164,14 @@ fn new(hs_fw: &HsFirmwareV2<'_>) -> Result<Self> {
hs_fw
.fw
.get(start..end)
- .and_then(Self::from_bytes_copy)
+ .and_then(|b| Self::read_from_bytes(b).ok())
.ok_or(EINVAL)
}
}
/// Header for code and data load offsets.
#[repr(C)]
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, FromBytes)]
struct HsLoadHeaderV2 {
// Offset at which the code starts.
os_code_offset: u32,
@@ -191,9 +185,6 @@ struct HsLoadHeaderV2 {
num_apps: u32,
}
-// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
-unsafe impl FromBytes for HsLoadHeaderV2 {}
-
impl HsLoadHeaderV2 {
/// Returns the load header contained in `hs_fw`.
///
@@ -205,7 +196,7 @@ fn new(hs_fw: &HsFirmwareV2<'_>) -> Result<Self> {
/// Header for app code loader.
#[repr(C)]
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, FromBytes)]
struct HsLoadHeaderV2App {
/// Offset at which to load the app code.
offset: u32,
@@ -213,9 +204,6 @@ struct HsLoadHeaderV2App {
len: u32,
}
-// SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability.
-unsafe impl FromBytes for HsLoadHeaderV2App {}
-
impl HsLoadHeaderV2App {
/// Returns the [`HsLoadHeaderV2App`] for app `idx` of `hs_fw`.
///
--
2.34.1
^ permalink raw reply related [flat|nested] 13+ messages in thread