ACK: [SRU][J/N:linux-bluefield][PATCH v5 0/1] mmc: core: Avoid bitfield RMW for claim/retune flags

[Alessio Faina]

On Tue, Mar 17, 2026 at 11:36:43AM -0400, Penghe Geng wrote:
> BugLink: https://bugs.launchpad.net/bugs/2143925
> 
> SRU Justification:
> 
> [Impact]
> 
> The host->claimed bit shared a word with retune flags. Writes to claimed
> in __mmc_claim_host() or retune_now in mmc_mq_queue_rq() can overwrite
> other bits when concurrent updates happen in other contexts, triggering
> spurious WARN_ON(!host->claimed).
> 
> [Fix]
> 
> Convert claimed, can_retune, retune_now and retune_paused to bool to remove shared-word coupling.
> 
> [Test Case]
> 
> * Boot BlueField-3 platform and verify that there are no instances of
>   "WARN_ON(!host->claimed)" call trace in dmesg log.
> 
> [Regression Potential]
> 
> None
> 
> [Notes]
> 
> This patch is already merged to the mainline.  The mainline commit is
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=901084c51a0a8fb42a3f37d2e9c62083c495f824
> 
> Penghe Geng (1):
>   mmc: core: Avoid bitfield RMW for claim/retune flags
> 
>  include/linux/mmc/host.h | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> [ChangeLog]
> 
> v2:
> - change title
> - add 'cherry picked from' line in commit message
> 
> v3:
> - resend only, start a new thread
> - no content changes from v2
> 
> v4:
> - relocate 'cherry picked from' line in commit message
> 
> v5:
> - fix email threading with no content changes
> 
> -- 
> 2.43.0

Acked-by: Alessio Faina <alessio.faina at canonical.com>