NACK: [SRU][J/N:linux-bluefield][PATCH 0/1] Cherry-pick upstreamed mmc core fix for bitfield RMW issues

Masahiro Yamada masahiro.yamada at canonical.com
Thu Mar 12 04:17:55 UTC 2026


On 3/12/26 04:44, 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(-)
>

The title "Cherry-pick upstreamed mmc core fix for bitfield RMW issues"

is incorrect.


It should be:

"mmc: core: Avoid bitfield RMW for claim/retune flags"


Also, the patch should have:

(cherry picked from commit 901084c51a0a8fb42a3f37d2e9c62083c495f824)





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