github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-07-28 10:09:10 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

gpu: nova-core: vbios: compute FWSEC-relative Falcon data offset

Browse Source 
Push the computation of the falcon data offset into a helper function.
The subtraction to create the offset should be checked, and by doing
this the check can be folded into the existing check in
`falcon_data_ptr`.

Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Eliot Courtney <ecourtney@nvidia.com>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Link: https://patch.msgid.link/20260525-fix-vbios-v5-10-e5e455251537@nvidia.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
This commit is contained in:
Eliot Courtney 2026-05-25 22:57:28 +09:00 committed by Danilo Krummrich
parent 8cf15cf264
commit b2a48fc068
1 changed files with 19 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
drivers/gpu/nova-core/vbios.rs
View File

@ -846,33 +846,29 @@ fn get_bit_token(&self, token_id: u8) -> Result<BitToken> {
BitToken::from_id(self, token_id)
}
/// Find the Falcon data pointer structure in the [`PciAtBiosImage`].
/// Find the Falcon data offset from the start of the FWSEC region.
///
/// This is just a 4 byte structure that contains a pointer to the Falcon data in the FWSEC
/// image.
fn falcon_data_ptr(&self) -> Result<u32> {
/// The BIT table contains a 4-byte pointer to the Falcon data. Testing shows this pointer
/// treats the PCI-AT and FWSEC images as logically contiguous even when an EFI image sits in
/// between them, so subtract the PCI-AT image size here to convert it to a FWSEC-relative
/// offset.
fn falcon_data_offset(&self) -> Result<usize> {
let token = self.get_bit_token(BIT_TOKEN_ID_FALCON_DATA)?;
// Make sure we don't go out of bounds
if usize::from(token.data_offset) + 4 > self.base.data.len() {
return Err(EINVAL);
}
// read the 4 bytes at the offset specified in the token
let offset = usize::from(token.data_offset);
let bytes: [u8; 4] = self.base.data[offset..offset + 4].try_into().map_err(|_| {
dev_err!(self.base.dev, "Failed to convert data slice to array\n");
EINVAL
})?;
let data_ptr = u32::from_le_bytes(bytes);
// Read the 4-byte falcon data pointer at the offset specified in the token.
let data = &self.base.data;
let (ptr, _) = data
.get(offset..)
.and_then(u32::from_bytes_copy_prefix)
.ok_or(EINVAL)?;
if (usize::from_safe_cast(data_ptr)) < self.base.data.len() {
dev_err!(self.base.dev, "Falcon data pointer out of bounds\n");
return Err(EINVAL);
}
Ok(data_ptr)
usize::from_safe_cast(ptr)
.checked_sub(data.len())
.ok_or(EINVAL)
.inspect_err(|_| {
dev_err!(self.base.dev, "Falcon data pointer out of bounds\n");
})
}
}
@ -989,15 +985,9 @@ fn setup_falcon_data(
pci_at_image: &PciAtBiosImage,
first_fwsec: &FwSecBiosBuilder,
) -> Result {
let mut offset = usize::from_safe_cast(pci_at_image.falcon_data_ptr()?);
let mut offset = pci_at_image.falcon_data_offset()?;
let mut pmu_in_first_fwsec = false;
// The falcon data pointer assumes that the PciAt and FWSEC images
// are contiguous in memory. However, testing shows the EFI image sits in
// between them. So calculate the offset from the end of the PciAt image
// rather than the start of it. Compensate.
offset -= pci_at_image.base.data.len();
// The offset is now from the start of the first Fwsec image, however
// the offset points to a location in the second Fwsec image. Since
// the fwsec images are contiguous, subtract the length of the first Fwsec