Hi Gary, On 9/15/26 13:18, Gary Guo wrote: > On Tue Sep 15, 2026 at 11:57 AM BST, Laura Nao wrote: >> SysMemBackend's IoCapable<u64> impl is currently gated on CONFIG_64BIT, >> copying the MMIO backend's restriction. MMIO needs that gate because >> readq() is not available on 32bit. System memory has no such dependency: >> a u64 volatile load/store compiles on any architecture, it's just not >> single-copy atomic on 32bit. >> >> Drop the gate so u64-backed types, such as bitfields, work on 32bit too. >> Document the non-atomicity at the impl instead of enforcing it at build >> time. >> >> Co-developed-by: Daniel Almeida <[email protected]> >> Signed-off-by: Daniel Almeida <[email protected]> >> Signed-off-by: Laura Nao <[email protected]> > > No. If you don't need atomicity, please use `copy_read` to read the value. > It'll > compile down to the same volatile read, just without atomicity guarantee. >
Ack, thanks for the feedback. I'll drop this in v2. Best, Laura
