[PATCH v2] gpu: nova-core: firmware: fwsec: use zeroed() to zero-pad buffers

[PATCH v2] gpu: nova-core: firmware: fwsec: use zeroed() to zero-pad buffers

[Thorsten Blum]

Use KVec::zeroed() to allocate the zero-padded microcode buffer and copy
the bootloader code into it. Also use KVVec::zeroed() to initialize the
firmware object's leading zero padding.

Signed-off-by: Thorsten Blum <blum@kernel.org>
---
Changes in v2:
- Add a // PANIC comment to copy_from_slice() (Danilo)
- v1: https://lore.kernel.org/r/20261006100442.80432-3-blum@kernel.org/
---
 drivers/gpu/nova-core/firmware/fwsec/bootloader.rs | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs b/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
index ec4d92317a93..1aa08ae8de78 100644
--- a/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
+++ b/drivers/gpu/nova-core/firmware/fwsec/bootloader.rs
@@ -137,10 +137,9 @@ pub(crate) fn new(
                 .align_up(Alignment::new::<{ falcon::MEM_BLOCK_ALIGNMENT }>())
                 .ok_or(EINVAL)?;
 
-            let mut ucode = KVec::with_capacity(aligned_code_size, GFP_KERNEL)?;
-            ucode.extend_from_slice(code, GFP_KERNEL)?;
-            ucode.resize(aligned_code_size, 0, GFP_KERNEL)?;
-
+            let mut ucode = KVec::zeroed(aligned_code_size, GFP_KERNEL)?;
+            // PANIC: ucode is sliced to code.len(); code.len() <= aligned_code_size.
+            ucode[..code.len()].copy_from_slice(code);
             ucode
         };
 
@@ -162,8 +161,7 @@ pub(crate) fn new(
                     .ok_or(EOVERFLOW)?
             };
 
-            let mut firmware_obj = KVVec::new();
-            firmware_obj.extend_with(align_padding, 0u8, GFP_KERNEL)?;
+            let mut firmware_obj = KVVec::zeroed(align_padding, GFP_KERNEL)?;
             firmware_obj.extend_from_slice(firmware.ucode.0.as_slice(), GFP_KERNEL)?;
 
             (