Re: [PATCH v3 5/6] powerpc/64: Add support for out-of-line static calls

2022-10-06 Thread Segher Boessenkool
On Thu, Oct 06, 2022 at 08:50:31PM +, Christophe Leroy wrote: > Le 06/10/2022 à 22:45, Segher Boessenkool a écrit : > > I meant just an indicative code size number... 100 bytes, 100kB, 100MB, > > or something like that :-) And, on 64 bit, which is what the question > > was about! > > Ah,

Re: [PATCH v3 5/6] powerpc/64: Add support for out-of-line static calls

2022-10-06 Thread Christophe Leroy
Le 06/10/2022 à 22:45, Segher Boessenkool a écrit : > On Thu, Oct 06, 2022 at 06:38:00PM +, Christophe Leroy wrote: >> Le 06/10/2022 à 20:22, Segher Boessenkool a écrit : >>> Long ago I built kernels that fit together with the boot firmware and a >>> root fs (busybox+dropbear essentially) in

Re: [PATCH v3 5/6] powerpc/64: Add support for out-of-line static calls

2022-10-06 Thread Segher Boessenkool
On Thu, Oct 06, 2022 at 06:38:00PM +, Christophe Leroy wrote: > Le 06/10/2022 à 20:22, Segher Boessenkool a écrit : > > Long ago I built kernels that fit together with the boot firmware and a > > root fs (busybox+dropbear essentially) in 4MB, but I doubt we can get > > close to that at all

Re: [PATCH v3 5/6] powerpc/64: Add support for out-of-line static calls

2022-10-06 Thread Christophe Leroy
Le 06/10/2022 à 20:22, Segher Boessenkool a écrit : > On Thu, Oct 06, 2022 at 11:39:50AM +1100, Michael Ellerman wrote: >> Christophe Leroy writes: >>> However, thinking out loudly, I'm wondering, could we make things any >>> simpler when CONFIG_MODULES is not selected, or is that a too much

Re: [PATCH v3 5/6] powerpc/64: Add support for out-of-line static calls

2022-10-06 Thread Segher Boessenkool
On Thu, Oct 06, 2022 at 11:39:50AM +1100, Michael Ellerman wrote: > Christophe Leroy writes: > > However, thinking out loudly, I'm wondering, could we make things any > > simpler when CONFIG_MODULES is not selected, or is that a too much > > corner case on PPC64 ? > > I'd say it's mostly a

Re: [PATCH v3 5/6] powerpc/64: Add support for out-of-line static calls

2022-10-05 Thread Benjamin Gray
On Thu, 2022-10-06 at 11:39 +1100, Michael Ellerman wrote: > Christophe Leroy writes: > > However, thinking out loudly, I'm wondering, could we make things > > any > > simpler when CONFIG_MODULES is not selected, or is that a too much > > corner case on PPC64 ? > > I'd say it's mostly a corner

Re: [PATCH v3 5/6] powerpc/64: Add support for out-of-line static calls

2022-10-05 Thread Michael Ellerman
Christophe Leroy writes: > Le 05/10/2022 à 07:32, Benjamin Gray a écrit : >> Implement static call support for 64 bit V2 ABI. This requires making >> sure the TOC is kept correct across kernel-module boundaries. As a >> secondary concern, it tries to use the local entry point of a target >>

Re: [PATCH v3 5/6] powerpc/64: Add support for out-of-line static calls

2022-10-05 Thread Christophe Leroy
Le 05/10/2022 à 07:32, Benjamin Gray a écrit : > Implement static call support for 64 bit V2 ABI. This requires making > sure the TOC is kept correct across kernel-module boundaries. As a > secondary concern, it tries to use the local entry point of a target > wherever possible. It does so by

[PATCH v3 5/6] powerpc/64: Add support for out-of-line static calls

2022-10-04 Thread Benjamin Gray
Implement static call support for 64 bit V2 ABI. This requires making sure the TOC is kept correct across kernel-module boundaries. As a secondary concern, it tries to use the local entry point of a target wherever possible. It does so by checking if both tramp & target are kernel code, and falls