Hi Julien,
On 27/01/2023 20:55, Julien Grall wrote:
>
>
> From: Julien Grall <jgr...@amazon.com>
>
> At the moment, the temporary mapping is only used when the virtual
> runtime region of Xen is clashing with the physical region.
>
> In follow-up patches, we will rework how secondary CPU bring-up works
> and it will be convenient to use the fixmap area for accessing
> the root page-table (it is per-cpu).
>
> Rework the code to use temporary mapping when the Xen physical address
> is not overlapping with the temporary mapping.
>
> This also has the advantage to simplify the logic to identity map
> Xen.
>
> Signed-off-by: Julien Grall <jgr...@amazon.com>
>
> ---
>
> Even if this patch is rewriting part of the previous patch, I decided
> to keep them separated to help the review.
>
> The "follow-up patches" are still in draft at the moment. I still haven't
> find a way to split them nicely and not require too much more work
> in the coloring side.
>
> I have provided some medium-term goal in the cover letter.
>
> Changes in v5:
> - Fix typo in a comment
> - No need to link boot_{second, third}_id again if we need to
> create a temporary area.
>
> Changes in v3:
> - Resolve conflicts after switching from "ldr rX, <label>" to
> "mov_w rX, <label>" in a previous patch
>
> Changes in v2:
> - Patch added
> ---
> xen/arch/arm/arm32/head.S | 85 +++++++--------------------------------
> 1 file changed, 15 insertions(+), 70 deletions(-)
>
> diff --git a/xen/arch/arm/arm32/head.S b/xen/arch/arm/arm32/head.S
> index df51550baa8a..93b0af114b0c 100644
> --- a/xen/arch/arm/arm32/head.S
> +++ b/xen/arch/arm/arm32/head.S
...
> @@ -675,33 +641,12 @@ remove_identity_mapping:
> /* r2:r3 := invalid page-table entry */
> mov r2, #0x0
> mov r3, #0x0
> - /*
> - * Find the first slot used. Remove the entry for the first
> - * table if the slot is not XEN_FIRST_SLOT.
> - */
Could you please add an empty line here to improve readability?
> + /* Find the first slot used and remove it */
Reviewed-by: Michal Orzel <michal.or...@amd.com>
~Michal
