Re: [PATCH v5 5/9] block: fail a short atomic pin in bio_iov_iter_get_pages()

[John Garry]

On 9/24/26 00:56, Tal Zussman wrote:
> On a partial page pin, __blkdev_direct_IO_simple() and
> __blkdev_direct_IO_async() submit what was pinned with REQ_ATOMIC set
> and leave the rest to the buffered fallback, tearing an IOCB_ATOMIC
> write.
>
> This can be triggered deterministically. A 16K pwritev2(RWF_ATOMIC)
> whose last page is PROT_NONE, on a scsi_debug device with atomic_wr=1,
> completes short with only three of the four pages written, violating
> RWF_ATOMIC semantics.

I don't mean to load more work, but a blktests case for this would be 
great. I am consider doing it if you are too busy.

Thanks!