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32fe1de5c1
KCSAN reports data races when accessing virtio ring fields that are concurrently written by the device (host). These are legitimate concurrent accesses where the CPU reads fields that the device updates via DMA-like mechanisms. Add accessor functions that use READ_ONCE() to properly annotate these device-writable fields and prevent compiler optimizations that could in theory break the code. This also serves as documentation showing which fields are shared with the device. The affected fields are: - Split ring: used->idx, used->ring[].id, used->ring[].len - Packed ring: desc[].flags, desc[].id, desc[].len This patch was partially written using the help of Kiro, an AI coding assistant, to automate the mechanical work of generating the inline function definition. Signed-off-by: Alexander Graf <graf@amazon.com> [jth: Add READ_ONCE in virtqueue_kick_prepare_split ] Co-developed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Alexander Graf <graf@amazon.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Message-ID: <20260131102810.1254845-1-johannes.thumshirn@wdc.com>
3983 lines
103 KiB
3983 lines
103 KiB