On 13.03.2025 16:01, Andrew Cooper wrote:
> On 13/03/2025 1:34 pm, Jan Beulich wrote:
>> Handling possible internal errors by just emitting a (debug-build-only)
>> log message can't be quite enough. Return error codes in those cases,
>> and have the caller propagate those up.
>>
>> Drop a pointless return path, rather than "inventing" an error code for
>> it.
>>
>> While touching the function declarator anyway also constify its first
>> parameter.
>>
>> Fixes: 476bbccc811c ("VT-d: fix MSI source-id of interrupt remapping")
>> Signed-off-by: Jan Beulich <jbeul...@suse.com>
>
> Reviewed-by: Andrew Cooper <andrew.coop...@citrix.com>,
Thanks.
> although...
>
>> --- a/xen/drivers/passthrough/vtd/intremap.c
>> +++ b/xen/drivers/passthrough/vtd/intremap.c
>> @@ -436,15 +436,13 @@ void cf_check io_apic_write_remap_rte(
>> __ioapic_write_entry(apic, pin, true, old_rte);
>> }
>>
>> -static void set_msi_source_id(struct pci_dev *pdev, struct iremap_entry
>> *ire)
>> +static int set_msi_source_id(const struct pci_dev *pdev,
>> + struct iremap_entry *ire)
>> {
>> u16 seg;
>> u8 bus, devfn, secbus;
>> int ret;
>>
>> - if ( !pdev || !ire )
>> - return;
>> -
>> seg = pdev->seg;
>> bus = pdev->bus;
>> devfn = pdev->devfn;
>> @@ -485,16 +483,21 @@ static void set_msi_source_id(struct pci
>> PCI_BDF(bus, devfn));
>> }
>> else
>> + {
>> dprintk(XENLOG_WARNING VTDPREFIX,
>> "d%d: no upstream bridge for %pp\n",
>> pdev->domain->domain_id, &pdev->sbdf);
>
> as you're doing cleanup, %pd here? Given DOM_IO for quarantine, I think
> it's more likely now than it used to be.
>
>> + return -ENXIO;
>> + }
>> break;
>>
>> default:
>> dprintk(XENLOG_WARNING VTDPREFIX, "d%d: unknown(%u): %pp\n",
>> pdev->domain->domain_id, pdev->type, &pdev->sbdf);
>
> Here too. Also, the "unknown(%u)" is less than ideal. "%pd: %pp
> unknown type %u\n" would be better.
To be honest this feels like going too far with unrelated cleanup here,
even if it's all in patch context. It would be different if at least I
touched those dprintk() invocations.
Jan
