Re: [PATCH v7 09/15] perf annotate-x86: Delete stale stack state on store of untracked register

[sashiko-bot@kernel.org]

> When a register without a tracked type is stored to a stack slot that
> previously held a valid type, the code currently performs an early return.
> This leaves the old type information intact in the stack state.
> 
> As a result, a stale type bug occurs:
> 1. A tracked register is stored into a stack slot.
> 2. The register becomes untracked/invalid (e.g., across a function call).
> 3. The now-untracked register is stored into the same stack slot.
> 4. Subsequent loads from that slot erroneously pick up the old stale type
>    because the stack entry was never invalidated.
> 
> Fix this by introducing delete_stack_state() to search and free a stack
> entry for a given offset. When storing an untracked or invalid source
> register into a stack location, call delete_stack_state() to delete the
> stale entry before returning.
> 
> Reviewed-by: Ian Rogers <irogers@google.com>
> Signed-off-by: Tengda Wu <wutengda@huaweicloud.com>

Sashiko has reviewed this patch and found no issues. It looks great!

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