Re: [PATCH v2 2/2] cxl/mbox: Use mapped errno to determine command status

[Li Ming]

在 2026/11/5 12:41, Alison Schofield 写道:
> On Tue, Nov 03, 2026 at 10:43:05AM +0800, Li Ming wrote:
> > cxl_mbox_cmd_rctable already maps all mailbox command return codes to
> > errno values. Use the returned errno directly instead of checking
> > mailbox return codes separately to determine whether a command succeeded
> > or failed.
> >
> > Signed-off-by: Li Ming <ming.li@xxxxxxxxxxxx>
> > ---
> > v2:
> > - New patch.
> > ---
> >   drivers/cxl/core/mbox.c | 6 +++---
> >   1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> > index 55828a836c01..bd91b03c4d21 100644
> > --- a/drivers/cxl/core/mbox.c
> > +++ b/drivers/cxl/core/mbox.c
> > @@ -270,9 +270,9 @@ int cxl_internal_send_cmd(struct cxl_mailbox *cxl_mbox,
> >   	if (rc)
> >   		return rc;
> >   
> > -	if (mbox_cmd->return_code != CXL_MBOX_CMD_RC_SUCCESS &&
> > -	    mbox_cmd->return_code != CXL_MBOX_CMD_RC_BACKGROUND)
> > -		return cxl_mbox_cmd_rc2errno(mbox_cmd);
> > +	rc = cxl_mbox_cmd_rc2errno(mbox_cmd);
> > +	if (rc)
> > +		return rc;
> Hi Ming,
>
> The existing code really seemed to want BACKGROUND as a special case, so
> I searched the history on this one,  Davidlohr and you discussed this in
> 2023 around sanitize[1] .
>
> I do think it is confusing and if we can just follow the table codes,
> that would be easier.

Hi Alison,

Thanks for your review.

I checked the link you shared, it is about the return code of a 
BACKGROUND cmd handling inside __cxl_pci_mbox_send_cmd(), because 
__cxl_pci_mbox_send_cmd() needs to handle both non-BACKGROUND and 
BACKGROUND cmds and returns the result. but in cxl_internal_send_cmd(), 
I think we can consider the cmd done whether it is a BACKGROUND command 
or not.

> I'll let Davidlohr dig in on this one.
Thanks.
> I read both these patches as cleanups but no bug to be fixed.

Sure, will drop the fixes tag.


Ming

> [1] https://lore.kernel.org/linux-cxl/mw5bsc5u72fdrgo7qovj6u2npg2asftzp3jeprwtmnvbvg7vet@fayzcxpurjl6/
>
> -- Alison
>
>
>
>
>
> >   
> >   	if (!out_size)
> >   		return 0;
> > --
> > 2.43.0