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Petr Beneš
7e5b662b28
This patch addresses a behavior discrepancy in the handling of altp2m views, where upon the creation and subsequent EPT violation, the page access permissions were incorrectly inherited from the hostp2m instead of respecting the altp2m default_access. Previously, when a new altp2m view was established with restrictive default_access permissions and activated via xc_altp2m_switch_to_view(), it failed to trigger an event on the first access violation. This behavior diverged from the intended mechanism, where the altp2m's default_access should dictate the initial permissions, ensuring proper event triggering on access violations. The correction involves modifying the handling mechanism to respect the altp2m view's default_access upon its activation, eliminating the need for setting memory access permissions for the entire altp2m range (e.g. within xen-access.c). This change not only aligns the behavior with the expected access control logic but also results in a significant performance improvement by reducing the overhead associated with setting memory access permissions across the altp2m range. Signed-off-by: Petr Beneš <w1benny@gmail.com> Acked-by: Tamas K Lengyel <tamas@tklengyel.com>