On Mon, May 18, 2026 at 07:01:04PM +0800, Bin Guo wrote:
> This series collects several small improvements to the migration
> subsystem:
>
> - Bug fix: off-by-one in multifd recv channel ID validation that
> could allow an out-of-bounds write (patch 5).
> - Micro-optimizations: cache migrate_multifd_channels() in hot
> paths (patches 7-8), use stack-allocated bitmap instead of
> heap (patch 4), avoid per-element heap churn in vmstate ptr
> marker field (patch 3).
> - Cleanups: collapse migration_fd_valid into a single boolean
> expression (patch 1), replace strcpy("") with explicit NUL
> termination (patch 2), merge thread-join and cleanup loops in
> multifd_recv_cleanup (patch 6).
>
> No functional change intended except for the off-by-one fix in
> patch 5.
>
> Bin Guo (8):
> migration/fd: collapse migration_fd_valid into single boolean
> expression
> migration/global_state: replace strcpy("") with explicit NUL
> termination
> migration/vmstate: avoid per-element heap churn in vmsd ptr marker
> field
> migration/savevm: use stack-allocated bitmap in
> configuration_validate_capabilities
> migration/multifd: fix off-by-one in recv channel ID validation
> migration/multifd: merge thread-join and cleanup loops in
> multifd_recv_cleanup
> migration/multifd: cache migrate_multifd_channels() in send/recv hot
> paths
> migration/multifd: cache channel count in multifd_send_sync_main
For patch 1, I tend to agree with Fabiano; I don't clearly see why the
oneliner is always better. Oneliners can be harder to read to some (for
most of the cases, myself included..).
For patch 6, I confess I can't see an issue with the current patch, but
since there's a discussion, let it happen.
I queued the rest, thanks.
--
Peter Xu
