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charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/14/24 10:29, Aruna Ramakrishna wrote: > This patch is a workaround for a bug where the PKRU value is not > restored to the init value before the signal handler is invoked. I don't think we should touch this with a ten foot pole without a test for it in tools/testing/selftests/mm/protection_keys.c. I'm not sure this is worth the trouble. Protection keys is not a security feature. This isn't a regression. It's been the behavior since day one. This really is a feature request for a behavioral improvement, not a bug fix. The need for this new feature is highly dependent on the threat model that it supports. I'm highly dubious that there's a true need to protect against an attacker with arbitrary write access in the same address space. We need to have a lot more information there. I haven't even more than glanced at the code. It looks pretty unspeakably ugly even at a glance.