By: Jon Masters (jcm.delete@this.jonmasters.org), March 13, 2021 7:25 pm
Room: Moderated Discussions
Linus Torvalds (torvalds.delete@this.linux-foundation.org) on March 13, 2021 12:18 pm wrote:
> The Intel version is basically "Yeah, the protected mode 80286 exception handling was bad,
> then 386 made it odder with the 32-bit extensions, and then syscall/sysenter made
> everything worse, and then the x86-64 extensions introduced even more problems.
> So let's add a mode bit where all the crap goes away".
That's exactly how I read it too. With the "FRED" architecture, you ought to be kill off legacy segmentation in future processors (at least as far as privileged software is concerned). The only real questions is "which Fred?". Fred Pollack came to mind but I don't think he was involved in the creation of the legacy segmentation schemes. Anyone know?
Jon.
> The Intel version is basically "Yeah, the protected mode 80286 exception handling was bad,
> then 386 made it odder with the 32-bit extensions, and then syscall/sysenter made
> everything worse, and then the x86-64 extensions introduced even more problems.
> So let's add a mode bit where all the crap goes away".
That's exactly how I read it too. With the "FRED" architecture, you ought to be kill off legacy segmentation in future processors (at least as far as privileged software is concerned). The only real questions is "which Fred?". Fred Pollack came to mind but I don't think he was involved in the creation of the legacy segmentation schemes. Anyone know?
Jon.
| Topic | Posted By | Date |
|---|---|---|
| x86 - why unite when you can fragment? | anonymou5 | 2021/03/12 06:16 PM |
| x86 - why unite when you can fragment? | Linus Torvalds | 2021/03/13 01:18 PM |
| x86 - why unite when you can fragment? | Jon Masters | 2021/03/13 07:25 PM |
| x86 - why unite when you can fragment? | Jon Masters | 2021/03/13 07:44 PM |
| x86 - why unite when you can fragment? | Yuhong Bao | 2021/03/13 08:49 PM |
| x86 - why unite when you can fragment? | tt | 2021/03/20 09:30 AM |
| x86 - why unite when you can fragment? | Andrey | 2021/03/14 04:15 PM |
| x86 - why unite when you can fragment? | Linus Torvalds | 2021/03/14 04:58 PM |
| x86 - why unite when you can fragment? | anonymou5 | 2021/03/14 05:31 PM |
| x86 - why unite when you can fragment? | anon2 | 2021/03/14 08:07 PM |
| Microkernel? | Anon | 2021/03/14 11:49 PM |
| Microkernel? | none | 2021/03/15 12:37 AM |
| Microkernel? | Anon | 2021/03/15 01:56 AM |
| Microkernel? | anon2 | 2021/03/15 01:58 AM |
| Microkernel? | Simon Farnsworth | 2021/03/15 03:12 AM |
| Microkernel? | anon2 | 2021/03/15 04:53 AM |
| Microkernel? | Simon Farnsworth | 2021/03/15 06:56 AM |
| Microkernel? | iz | 2021/03/15 08:10 AM |
| Microkernel? | Anon | 2021/03/15 09:05 AM |
| Microkernel? | iz | 2021/03/16 01:25 AM |
| Microkernel? | Andrey | 2021/03/16 02:54 AM |
| Microkernel? | iz | 2021/03/16 08:36 AM |
| Microkernel? | Andrey | 2021/03/16 10:06 AM |
| Microkernel? | anonymou5 | 2021/03/16 11:44 AM |
| Microkernel? | iz | 2021/03/21 02:58 AM |
| Microkernel? | Andrey | 2021/03/21 09:34 AM |
| Microkernel? | anon2 | 2021/03/15 08:31 AM |
| Microkernel? | Simon Farnsworth | 2021/03/16 04:42 AM |
| Microkernel? | Gabriele Svelto | 2021/03/15 03:21 AM |
| Microkernel? | anon2 | 2021/03/15 04:56 AM |
| Microkernel? | Gabriele Svelto | 2021/03/15 10:41 AM |
| Microkernel? | anon2 | 2021/03/15 08:00 PM |
| Microkernel? | Gabriele Svelto | 2021/03/16 07:23 AM |
| Microkernel? | anon2 | 2021/03/16 05:13 PM |
| Microkernel? | anon2 | 2021/03/16 05:16 PM |
| Microkernel? | Gian-Carlo Pascutto | 2021/03/16 01:40 PM |
| Microkernel? | anon2 | 2021/03/16 05:53 PM |
| Microkernel? | Linus Torvalds | 2021/03/16 07:25 PM |
| Microkernel? | Doug S | 2021/03/17 09:30 AM |
| Microkernel? | Linus Torvalds | 2021/03/17 10:30 AM |
| Microkernel? | Brendan | 2021/03/17 10:56 PM |
| Microkernel? | Michael S | 2021/03/18 03:47 AM |
| Microkernel? | Brendan | 2021/03/18 09:07 AM |
| Microkernel? | Jose | 2021/03/18 09:35 AM |
| Microkernel? | zArchJon | 2021/03/18 05:42 PM |
| Transputer | RichardC | 2021/03/17 09:47 AM |
| Microkernel? | dmcq | 2021/03/17 11:15 AM |
| Microkernel? | Linus Torvalds | 2021/03/17 11:59 AM |
| Microkernel? | dmcq | 2021/03/17 12:38 PM |
| Microkernel? | Adrian | 2021/03/17 01:00 PM |
| Microkernel? | Ana R. Riano | 2021/03/18 04:33 AM |
| Microkernel? | ⚛ | 2021/04/30 04:52 PM |
| Microkernel? | NvaxPlus | 2021/03/17 11:48 AM |
| Microkernel? | Michael S | 2021/03/18 03:32 AM |
| Microkernel? | Adrian | 2021/03/18 04:12 AM |
| Microkernel? | dmcq | 2021/03/18 06:30 AM |
| Microkernel? | dmcq | 2021/03/18 06:55 AM |
| Microkernel? | Adrian | 2021/03/18 08:35 AM |
| Microkernel? | --- | 2021/03/18 09:49 AM |
| Microkernel? | dmcq | 2021/03/18 10:59 AM |
| Microkernel? | dmcq | 2021/03/18 04:09 PM |
| Microkernel? | --- | 2021/03/18 09:27 AM |
| Microkernel? | Kalle A. Sandström | 2021/03/20 06:34 AM |
| Microkernel? | --- | 2021/03/20 08:35 AM |
| Microkernel? | anon2 | 2021/03/21 05:29 PM |
| Microkernel? | dmcq | 2021/03/15 04:06 AM |
| Microkernel? | anon2 | 2021/03/15 04:59 AM |
| Microkernel? | dmcq | 2021/03/15 11:51 AM |
| Microkernel? | anon2 | 2021/03/15 08:31 PM |
| Microkernel? | dmcq | 2021/03/16 09:17 AM |
| Microkernel? | Jukka Larja | 2021/03/16 11:22 AM |
| Microkernel? | dmcq | 2021/03/16 04:06 PM |
| Microkernel? | Jukka Larja | 2021/03/17 03:42 AM |
| Microkernel? | dmcq | 2021/03/17 07:00 AM |
| Microkernel? | anon2 | 2021/03/16 05:26 PM |
| Microkernel? | --- | 2021/03/16 10:07 AM |
| Microkernel? | -.- | 2021/03/15 08:15 PM |
| Microkernel? | anon2 | 2021/03/15 09:18 PM |
| Microkernel? | Foo_ | 2021/03/16 03:37 AM |
| Read the thread (NT) | anon2 | 2021/03/16 05:27 PM |
| Already did (NT) | Foo_ | 2021/03/17 02:55 AM |
| Already did | anon2 | 2021/03/17 03:46 AM |
| Already did | Etienne Lorrain | 2021/03/18 02:31 AM |
| Microkernel? | -.- | 2021/03/17 05:04 AM |
| Microkernel? | Gabriele Svelto | 2021/03/17 08:53 AM |
| Microkernel? | -.- | 2021/03/17 02:43 PM |
| Microkernel? | dmcq | 2021/03/16 08:40 AM |
| x86 - why unite when you can fragment? | Konrad Schwarz | 2021/03/17 10:19 AM |
| x86 - why unite when you can fragment? | anonon | 2021/03/15 07:37 AM |