Re: [PATCH v2] xen/arm: Reorder SCI resource cleanup in domain destruction

[Julien Grall <julien@xxxxxxx>]

(+ Release manager)

Hi,

On 14/09/2025 14:26, Oleksii Moisieiev wrote:
> Move the SCI (System Control and Management Interface) resource cleanup
> earlier in the domain_relinquish_resources() sequence to ensure proper
> cleanup ordering during domain destruction.
>
> The SCI cleanup is now performed before TEE (Trusted Execution Environment)
> cleanup rather than after P2M mapping cleanup. This reordering ensures that
> SCI resources are properly released before other subsystems that might
> depend on them are torn down.
>
> This change addresses potential resource cleanup dependencies where SCI
> resources need to be released before P2M mappings are cleaned up, preventing
> potential issues during domain destruction on ARM platforms with SCI support.
>
> Fixes: e2cc10867b (xen/arm: add generic SCI subsystem, 2025-09-04)
I am not sure where you found this syntax. This is not the one we use 
for Xen. It should be:
Fixes: <commit-id> ("<patch-subject>")

Where the commit-id is 12 characters. For this patch it should be:

Fixes: e2cc10867b63 ("xen/arm: add generic SCI subsystem")

> Signed-off-by: Oleksii Moisieiev <oleksii_moisieiev@xxxxxxxx>
> --->
> Changes in v2:
> - rearrange enum by placing PROG_sci before PROG_tee
> - add "Fixes:" tag
>
>   xen/arch/arm/domain.c | 11 ++++++-----
>   1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
> index 1a8585d02b..e36719bce4 100644
> --- a/xen/arch/arm/domain.c
> +++ b/xen/arch/arm/domain.c
> @@ -1042,6 +1042,7 @@ static int relinquish_memory(struct domain *d, struct 
> page_list_head *list)
>    */
>   enum {
>       PROG_pci = 1,
> +    PROG_sci,
Can you confirm this is fine to release the SCI resources *after* we 
releases the devices? Does this mean they are not linked somehow? For 
instance, if a device is re-assigned to another VM, could it fail 
because the associated (?) SCI resources were not yet released?
Cheers,

--
Julien Grall