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charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <5a89e49fe1f9d6ee2c72af411d40e2dbb1299759.camel@intel.com> X-Rspam-User: X-Rspamd-Queue-Id: F11614026C X-Rspamd-Server: rspam01 X-Stat-Signature: q3bapeiwd3fgu5nszcxgtoktwfjh6t5w X-HE-Tag: 1731626379-746934 X-HE-Meta: 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 gEDfjc4a abavZvPxiqjsKbebaw9izQR4DNJX5IZwtEJApCyP48UcjTXqMRYPxNd2FShfJMyifJ4xShnNTHC5F7rirnQg20G4tPAPVdmS1tQYm1xdKf+loiatpXM7wiGizAmfvNXWNX9k6HXDcZBNpu71KRo1aG5SEdoUHy5ACVeN4cZ35gId2Cd8g+UarqFu/gPNi639ZpoWbrq9EAMf1HoN6/pJqsOhqqxudlL6DMtwjnILd1/Eg9QUSWldS8Pt+L9VDYd4srY4CIxKJcywyXms7A1VMi0Giwp3Xez5lbuF7uVkHwQ1v/gm24/n/MqhZybfIYDDZumsn9Z23hqOiYhryydDUQRo4DnyvCdVyS7S96qMl2Qy6JFOMWYMQw6FSRSAdX0QhcK8O3lfDGsig30xjzVKEgClRitSfNREt7wywRxk/LwSYiphvyA24x7m3c68jtKQLjBSf7b9BijPEArI= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Nov 01, 2024 at 09:47:25PM +0000, Edgecombe, Rick P wrote: >On Wed, 2024-10-16 at 14:57 -0700, Deepak Gupta wrote: >> VM_SHADOW_STACK (alias to VM_HIGH_ARCH_5) is used to encode shadow stack >> VMA on three architectures (x86 shadow stack, arm GCS and RISC-V shadow >> stack). In case architecture doesn't implement shadow stack, it's VM_NONE >> Introducing a helper `is_shadow_stack_vma` to determine shadow stack vma >> or not. > >I don't understand why we need this. IIRC was some discussion about wanting to >abstract different ways of testing for shadow stack VMAs for different >architectures since risc-v was going to do it differently. But now this says >they are all the same, so what's wrong with the open coded check? > Yeah it was born out of the need due to risc-v overloading `VM_WRITE`. Given that's out of the door, this helper is not useful for that need anymore. However during rebasing I saw certain vma helpers were re-organized in a new file `vma.h` and there was helper for stack as well. So I kept it. I don't know if it's helpful or harmful. Let me know, I can let it go as well.