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x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Stat-Signature: 1phjobrczunf1pcm49nbyd3m9qkbkip6 X-Rspamd-Queue-Id: E1B4D4001E X-Rspamd-Server: rspam11 X-HE-Tag: 1729265013-743920 X-HE-Meta: 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 lh70cpwV x7+bWeV7ec3/bu8lQrCxXDQoKfsBdalXA8sWsFMzVUddCmZB4s6J9hzcY/aQqWFpwzMCeZDXfWOrV4Sxi1W1nKbiUH5SYmlu9VKAKcJ/xOfFfdozzc2yswsuis7rUVhqykK+szaosOZacEFW5BsIuqOcl9AuF0MfpT8j+Inc55BsZRZ5wLC8NEnQghZftR9RF0Q73XelCNAfhYe2c1aW+KPA3vHTDmFkai6xCf3r8/aOKpGThCJYQmHUEY9EK3bZzUctEJQfC7GilTaYaAIWkPfelPatuYqqnZjTP1lp89SHeX3cGhuX2CMEHZf+JP1V2bL1gl5Um+Ya73w91K5lzCvA7E54n6Dn3WCxB 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 Tue, 15 Oct 2024 12:09:38 +0100 Ryan Roberts wrote: > > > > Not to mention, when function graph tracing is enabled, this gets triggered > > for *every* function call! So I do not want any runtime test done. Every > > nanosecond counts in this code path. > > > > If anything, this needs to be moved to initialization and checked once, if > > it fails, gives a WARN_ON() and disables function graph tracing. > > I'm hoping my suggestion above to decouple SHADOW_STACK_SIZE from PAGE_SIZE is > acceptable and simpler? If not, happy to do as you suggest here. Yeah, I think we can do that. In fact, I'm thinking it should turn into a kmem_cache item that doesn't have to be a power of two (but must be evenly divisible by the size of long). I'll write up a patch. -- Steve