Re: [PATCH 13/14] block: Allow REQ_FUA|REQ_READ

Jens Axboe
2025-03-15T16:47:11Z

On 3/11/25 2:15 PM, Kent Overstreet wrote:
> REQ_FUA|REQ_READ means "do a read that bypasses the controller cache",
> the same as writes.
>
> This is useful for when the filesystem gets a checksum error, it's
> possible that a bit was flipped in the controller cache, and when we
> retry we want to retry the entire IO, not just from cache.
>
> The nvme driver already passes through REQ_FUA for reads, not just
> writes, so disabling the warning is sufficient to start using it, and
> bcachefs is implementing additional retries for checksum errors so can
> immediately use it.

This one got effectively nak'ed by various folks here:

> Link: https://lore.kernel.org/linux-block/20250311133517.3095878-1-kent.overstreet@linux.dev/

yet it's part of this series and in linux-next? Hmm?

--
Jens Axboe