Re: [PATCH] iommu/vt-d: Fix CACHE_TAG_NESTING_DEVTLB polluting shared variables in flush loop

[Baolu Lu]

On 6/23/26 14:01, Guanghui Feng wrote:
> In cache_tag_flush_range(), the CACHE_TAG_NESTING_DEVTLB case modifies the
> shared local variables 'addr' and 'mask' before falling through to
> CACHE_TAG_DEVTLB. This causes all subsequent CACHE_TAG_DEVTLB entries in
> the same loop iteration to incorrectly use the full-range flush parameters
> (addr=0, mask=MAX_AGAW_PFN_WIDTH) instead of the precisely calculated PSI
> range. This is not the intended behavior, as regular DEVTLB entries should
> always perform targeted range-based invalidation.
>
> Fix this by having CACHE_TAG_NESTING_DEVTLB directly call
> cache_tag_flush_devtlb_psi() with the full-range constants and break,
> instead of modifying shared variables and falling through. This ensures
> CACHE_TAG_DEVTLB always uses the original calculated addr and mask for
> precise range flush.
>
> Signed-off-by: Guanghui Feng<guanghuifeng@xxxxxxxxxxxxxxxxx>
> Signed-off-by: Guixin Liu<kanie@xxxxxxxxxxxxxxxxx>
> ---
>   drivers/iommu/intel/cache.c | 5 ++---
>   1 file changed, 2 insertions(+), 3 deletions(-)

Queued for v7.3-rc1. Thanks a lot!