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group holds all messages Topicbox-Message-UUID: fdae692e-ec00-11f0-893a-d06110c0285f Archived-At: =?UTF-8?B?PGh0dHBzOi8vOWZhbnMudG9waWNib3guY29tL2dyb3Vwcy85?= =?UTF-8?B?ZmFucy9UZjZlMGIxYjNmODBkZjgyMS1NNWNhNDRmMjFjMzE0MDNiNmRkMmE4?= =?UTF-8?B?MGIwPg==?= List-Help: List-Id: "9fans" <9fans.9fans.net> List-Post: List-Software: Topicbox v0 List-Subscribe: Precedence: list Reply-To: 9fans <9fans@9fans.net> List-Unsubscribe: , Topicbox-Delivery-ID: 2:9fans:437d30aa-c441-11e9-8a57-d036212d11b0:522be890-2105-11eb-b15e-8d699134e1fa:M5ca44f21c31403b6dd2a80b0:1:h4AeYlKg2tCtzhKWc9RqHvNV4tAOobPgJMbGM_qLLIM rminnich@gmail.com: > you can't avoid M mode on riscv, ever. There are several trap cases that > will drop you in to M mode. I thought avoiding M mode was forced on you by the SBI implementation (firmware), which intercepts M mode traps and delegates them to S mode (if it feels like it). That's my recollection from working with the Polarfire Icicle, but it's a few years back. Or are you designing for a bare metal platform with no SBI? Are there any riscv implementations on the market which allow kernel and user mode to run with different XLEN, and thus enable a 64-bit kernel to host 32-bit processes? If so, I think that implies that you would want user address space to start at (or near) zero. ------------------------------------------ 9fans: 9fans Permalink: https://9fans.topicbox.com/groups/9fans/Tf6e0b1b3f80df821-M5ca44= f21c31403b6dd2a80b0 Delivery options: https://9fans.topicbox.com/groups/9fans/subscription