| Message ID | 20230408115936.6631-1-jiaxun.yang@flygoat.com (mailing list archive) |
|---|---|
| State | Rejected |
| Headers | show |
| Series | MIPS: Set better default CPU model and kernel code model | expand |
On Sat, Apr 08, 2023 at 12:59:36PM +0100, Jiaxun Yang wrote: > Set default CPU model to Release 2 CPUs (MIPS64R2 if 64 bit CPU > is present, otherwise MIPS32R2) to get better feature coverage > on various default configs. > > Also set default kernel code model to 64 bit since nowadays it > doesn't make much sense to run 32 bit kernel on a 64 bit system. > > Reported-by: Guenter Roeck <linux@roeck-us.net> > Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> > --- > arch/mips/Kconfig | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig > index ecc7a755fae6..1d681dd87bb0 100644 > --- a/arch/mips/Kconfig > +++ b/arch/mips/Kconfig > @@ -1260,6 +1260,8 @@ menu "CPU selection" > > choice > prompt "CPU type" > + default CPU_MIPS64_R2 if SYS_HAS_CPU_MIPS64_R2 > + default CPU_MIPS32_R2 if SYS_HAS_CPU_MIPS32_R2 > default CPU_R4X00 I don't think this makes things better. For systems with multiple possible CPU choices it's quite easy to get a kernel compiled for the wrong ISA. > > config CPU_LOONGSON64 > @@ -2007,6 +2009,7 @@ menu "Kernel type" > > choice > prompt "Kernel code model" > + default 64BIT I don't buy your "nowadays" argument. My SGI Indy still has 64Bit CPUs and has not much reason to run a 64bit kernel. Thomas.
> 2023年4月12日 14:31，Thomas Bogendoerfer <tsbogend@alpha.franken.de> 写道： > > On Sat, Apr 08, 2023 at 12:59:36PM +0100, Jiaxun Yang wrote: >> Set default CPU model to Release 2 CPUs (MIPS64R2 if 64 bit CPU >> is present, otherwise MIPS32R2) to get better feature coverage >> on various default configs. >> >> Also set default kernel code model to 64 bit since nowadays it >> doesn't make much sense to run 32 bit kernel on a 64 bit system. >> >> Reported-by: Guenter Roeck <linux@roeck-us.net> >> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> >> --- >> arch/mips/Kconfig | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig >> index ecc7a755fae6..1d681dd87bb0 100644 >> --- a/arch/mips/Kconfig >> +++ b/arch/mips/Kconfig >> @@ -1260,6 +1260,8 @@ menu "CPU selection" >> >> choice >> prompt "CPU type" >> + default CPU_MIPS64_R2 if SYS_HAS_CPU_MIPS64_R2 >> + default CPU_MIPS32_R2 if SYS_HAS_CPU_MIPS32_R2 >> default CPU_R4X00 > > I don't think this makes things better. For systems with multiple > possible CPU choices it's quite easy to get a kernel compiled for > the wrong ISA. Well this is only for best allmodconfig coverage. Or at least: default CPU_MIPS32_R2 if MIPS_GENERIC_KERNEL Can make things better. > >> >> config CPU_LOONGSON64 >> @@ -2007,6 +2009,7 @@ menu "Kernel type" >> >> choice >> prompt "Kernel code model" >> + default 64BIT > > I don't buy your "nowadays" argument. My SGI Indy still has 64Bit CPUs > and has not much reason to run a 64bit kernel. I see, I’ll leave it here. Thanks - Jiaxun > > Thomas. > > -- > Crap can work. Given enough thrust pigs will fly, but it's not necessarily a > good idea. [ RFC1925, 2.3 ]
On Wed, Apr 12, 2023 at 03:42:21PM +0100, Jiaxun Yang wrote: > > > > 2023年4月12日 14:31，Thomas Bogendoerfer <tsbogend@alpha.franken.de> 写道： > > > > On Sat, Apr 08, 2023 at 12:59:36PM +0100, Jiaxun Yang wrote: > >> Set default CPU model to Release 2 CPUs (MIPS64R2 if 64 bit CPU > >> is present, otherwise MIPS32R2) to get better feature coverage > >> on various default configs. > >> > >> Also set default kernel code model to 64 bit since nowadays it > >> doesn't make much sense to run 32 bit kernel on a 64 bit system. > >> > >> Reported-by: Guenter Roeck <linux@roeck-us.net> > >> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> > >> --- > >> arch/mips/Kconfig | 3 +++ > >> 1 file changed, 3 insertions(+) > >> > >> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig > >> index ecc7a755fae6..1d681dd87bb0 100644 > >> --- a/arch/mips/Kconfig > >> +++ b/arch/mips/Kconfig > >> @@ -1260,6 +1260,8 @@ menu "CPU selection" > >> > >> choice > >> prompt "CPU type" > >> + default CPU_MIPS64_R2 if SYS_HAS_CPU_MIPS64_R2 > >> + default CPU_MIPS32_R2 if SYS_HAS_CPU_MIPS32_R2 > >> default CPU_R4X00 > > > > I don't think this makes things better. For systems with multiple > > possible CPU choices it's quite easy to get a kernel compiled for > > the wrong ISA. > > Well this is only for best allmodconfig coverage. > > Or at least: > default CPU_MIPS32_R2 if MIPS_GENERIC_KERNEL > > Can make things better. not if there is the option SYS_HAS_CPU_R4X00 for MIPS_GENERIC_KERNEL selected. I've reverted the commit doing this, but still this is IMHO the wrong way forward. Thomas.
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index ecc7a755fae6..1d681dd87bb0 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -1260,6 +1260,8 @@ menu "CPU selection" choice prompt "CPU type" + default CPU_MIPS64_R2 if SYS_HAS_CPU_MIPS64_R2 + default CPU_MIPS32_R2 if SYS_HAS_CPU_MIPS32_R2 default CPU_R4X00 config CPU_LOONGSON64 @@ -2007,6 +2009,7 @@ menu "Kernel type" choice prompt "Kernel code model" + default 64BIT help You should only select this option if you have a workload that actually benefits from 64-bit processing or if your machine has
Set default CPU model to Release 2 CPUs (MIPS64R2 if 64 bit CPU is present, otherwise MIPS32R2) to get better feature coverage on various default configs. Also set default kernel code model to 64 bit since nowadays it doesn't make much sense to run 32 bit kernel on a 64 bit system. Reported-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> --- arch/mips/Kconfig | 3 +++ 1 file changed, 3 insertions(+)