diff mbox series

[v3] RISC-V: Add CONFIG_{NON,}PORTABLE

Message ID 20220521193356.26562-1-palmer@rivosinc.com (mailing list archive)
State New, archived
Headers show
Series [v3] RISC-V: Add CONFIG_{NON,}PORTABLE | expand

Commit Message

Palmer Dabbelt May 21, 2022, 7:33 p.m. UTC 
From: Palmer Dabbelt <palmer@rivosinc.com>

The RISC-V port has collected a handful of options that are
fundamentally non-portable.  To prevent users from shooting themselves
in the foot, hide them all behind a config entry that explicitly calls
out that non-portable binaries may be produced.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
Changes since v2:

* Update the nommu and rv32 defconfigs.  I'm still getting some ugliness
  like

    $ make.riscv rv32_defconfig
    *** Default configuration is based on 'defconfig'
    #
    # configuration written to .config
    #
    Using .config as base
    Merging ./arch/riscv/configs/32-bit.config
    Value of CONFIG_PORTABLE is redefined by fragment ./arch/riscv/configs/32-bit.config:
    Previous value: CONFIG_PORTABLE=y
    New value: # CONFIG_PORTABLE is not set
    
    Value of CONFIG_NONPORTABLE is redefined by fragment ./arch/riscv/configs/32-bit.config:
    Previous value: # CONFIG_NONPORTABLE is not set
    New value: CONFIG_NONPORTABLE=y
    
    #
    # merged configuration written to .config (needs make)
    #
    .config:3831:warning: override: ARCH_RV32I changes choice state
    #
    # configuration written to .config
    #

  not sure if there's a better way to do this.

Changes since v1:

* Fix a bunch of spelling mistakes.
* Move NONPORTABLE under the "Platform type" sub-heading.
* Fix the rv32i dependency.

---
 arch/riscv/Kconfig                            | 28 +++++++++++++++++--
 arch/riscv/configs/32-bit.config              |  2 ++
 arch/riscv/configs/nommu_k210_defconfig       |  1 +
 .../riscv/configs/nommu_k210_sdcard_defconfig |  1 +
 arch/riscv/configs/nommu_virt_defconfig       |  1 +
 arch/riscv/configs/rv32_defconfig             |  1 +
 6 files changed, 32 insertions(+), 2 deletions(-)

Comments

Atish Patra May 22, 2022, 8:09 a.m. UTC | #1 
On Sat, May 21, 2022 at 1:47 PM Palmer Dabbelt <palmer@rivosinc.com> wrote:
>
> From: Palmer Dabbelt <palmer@rivosinc.com>
>
> The RISC-V port has collected a handful of options that are
> fundamentally non-portable.  To prevent users from shooting themselves
> in the foot, hide them all behind a config entry that explicitly calls
> out that non-portable binaries may be produced.
>
> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
> ---
> Changes since v2:
>
> * Update the nommu and rv32 defconfigs.  I'm still getting some ugliness
>   like
>
>     $ make.riscv rv32_defconfig
>     *** Default configuration is based on 'defconfig'
>     #
>     # configuration written to .config
>     #
>     Using .config as base
>     Merging ./arch/riscv/configs/32-bit.config
>     Value of CONFIG_PORTABLE is redefined by fragment ./arch/riscv/configs/32-bit.config:
>     Previous value: CONFIG_PORTABLE=y
>     New value: # CONFIG_PORTABLE is not set
>
>     Value of CONFIG_NONPORTABLE is redefined by fragment ./arch/riscv/configs/32-bit.config:
>     Previous value: # CONFIG_NONPORTABLE is not set
>     New value: CONFIG_NONPORTABLE=y
>
>     #
>     # merged configuration written to .config (needs make)
>     #
>     .config:3831:warning: override: ARCH_RV32I changes choice state
>     #
>     # configuration written to .config
>     #
>
>   not sure if there's a better way to do this.
>
> Changes since v1:
>
> * Fix a bunch of spelling mistakes.
> * Move NONPORTABLE under the "Platform type" sub-heading.
> * Fix the rv32i dependency.
>
> ---
>  arch/riscv/Kconfig                            | 28 +++++++++++++++++--
>  arch/riscv/configs/32-bit.config              |  2 ++
>  arch/riscv/configs/nommu_k210_defconfig       |  1 +
>  .../riscv/configs/nommu_k210_sdcard_defconfig |  1 +
>  arch/riscv/configs/nommu_virt_defconfig       |  1 +
>  arch/riscv/configs/rv32_defconfig             |  1 +
>  6 files changed, 32 insertions(+), 2 deletions(-)
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index f863065b478c..cd67b09a80f5 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -222,6 +222,21 @@ source "arch/riscv/Kconfig.erratas"
>
>  menu "Platform type"
>
> +config NONPORTABLE
> +       bool "Allow configurations that result in non-portable kernels"
> +       help
> +         RISC-V kernel binaries are compatible between all known systems
> +         whenever possible, but there are some use cases that can only be
> +         satisfied by configurations that result in kernel binaries that are
> +         not portable between systems.
> +
> +         Selecting N does not guarantee kernels will be portable to all known
> +         systems.  Selecting any of the options guarded by NONPORTABLE will
> +         result in kernel binaries that are unlikely to be portable between
> +         systems.
> +
> +         If unsure, say N.
> +
>  choice
>         prompt "Base ISA"
>         default ARCH_RV64I
> @@ -231,6 +246,7 @@ choice
>
>  config ARCH_RV32I
>         bool "RV32I"
> +       depends on NONPORTABLE
>         select 32BIT
>         select GENERIC_LIB_ASHLDI3
>         select GENERIC_LIB_ASHRDI3
> @@ -541,6 +557,7 @@ config STACKPROTECTOR_PER_TASK
>
>  config PHYS_RAM_BASE_FIXED
>         bool "Explicitly specified physical RAM address"
> +       depends on NONPORTABLE
>         default n
>
>  config PHYS_RAM_BASE
> @@ -554,7 +571,7 @@ config PHYS_RAM_BASE
>
>  config XIP_KERNEL
>         bool "Kernel Execute-In-Place from ROM"
> -       depends on MMU && SPARSEMEM
> +       depends on MMU && SPARSEMEM && NONPORTABLE
>         # This prevents XIP from being enabled by all{yes,mod}config, which
>         # fail to build since XIP doesn't support large kernels.
>         depends on !COMPILE_TEST
> @@ -594,9 +611,16 @@ endmenu
>
>  config BUILTIN_DTB
>         bool
> -       depends on OF
> +       depends on OF && NONPORTABLE
>         default y if XIP_KERNEL
>
> +config PORTABLE
> +       bool
> +       default !NONPORTABLE
> +       select EFI
> +       select OF
> +       select MMU
> +
>  menu "Power management options"
>
>  source "kernel/power/Kconfig"
> diff --git a/arch/riscv/configs/32-bit.config b/arch/riscv/configs/32-bit.config
> index 43f41323b67e..f6af0f708df4 100644
> --- a/arch/riscv/configs/32-bit.config
> +++ b/arch/riscv/configs/32-bit.config
> @@ -1,2 +1,4 @@
>  CONFIG_ARCH_RV32I=y
>  CONFIG_32BIT=y
> +# CONFIG_PORTABLE is not set
> +CONFIG_NONPORTABLE=y
> diff --git a/arch/riscv/configs/nommu_k210_defconfig b/arch/riscv/configs/nommu_k210_defconfig
> index 2438fa39f8ae..96fe8def644c 100644
> --- a/arch/riscv/configs/nommu_k210_defconfig
> +++ b/arch/riscv/configs/nommu_k210_defconfig
> @@ -28,6 +28,7 @@ CONFIG_EMBEDDED=y
>  CONFIG_SLOB=y
>  # CONFIG_MMU is not set
>  CONFIG_SOC_CANAAN=y
> +CONFIG_NONPORTABLE=y
>  CONFIG_SMP=y
>  CONFIG_NR_CPUS=2
>  CONFIG_CMDLINE="earlycon console=ttySIF0"
> diff --git a/arch/riscv/configs/nommu_k210_sdcard_defconfig b/arch/riscv/configs/nommu_k210_sdcard_defconfig
> index 9a133e63ae5b..379740654373 100644
> --- a/arch/riscv/configs/nommu_k210_sdcard_defconfig
> +++ b/arch/riscv/configs/nommu_k210_sdcard_defconfig
> @@ -20,6 +20,7 @@ CONFIG_EMBEDDED=y
>  CONFIG_SLOB=y
>  # CONFIG_MMU is not set
>  CONFIG_SOC_CANAAN=y
> +CONFIG_NONPORTABLE=y
>  CONFIG_SMP=y
>  CONFIG_NR_CPUS=2
>  CONFIG_CMDLINE="earlycon console=ttySIF0 root=/dev/mmcblk0p1 rootwait ro"
> diff --git a/arch/riscv/configs/nommu_virt_defconfig b/arch/riscv/configs/nommu_virt_defconfig
> index 5269fbb6b4fc..1a56eda5ce46 100644
> --- a/arch/riscv/configs/nommu_virt_defconfig
> +++ b/arch/riscv/configs/nommu_virt_defconfig
> @@ -25,6 +25,7 @@ CONFIG_EXPERT=y
>  CONFIG_SLOB=y
>  # CONFIG_MMU is not set
>  CONFIG_SOC_VIRT=y
> +CONFIG_NONPORTABLE=y
>  CONFIG_SMP=y
>  CONFIG_CMDLINE="root=/dev/vda rw earlycon=uart8250,mmio,0x10000000,115200n8 console=ttyS0"
>  CONFIG_CMDLINE_FORCE=y
> diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig
> index 7e5efdc3829d..77bdb1d05a88 100644
> --- a/arch/riscv/configs/rv32_defconfig
> +++ b/arch/riscv/configs/rv32_defconfig
> @@ -18,6 +18,7 @@ CONFIG_EXPERT=y
>  CONFIG_PROFILING=y
>  CONFIG_SOC_SIFIVE=y
>  CONFIG_SOC_VIRT=y
> +CONFIG_NONPORTABLE=y
>  CONFIG_ARCH_RV32I=y
>  CONFIG_SMP=y
>  CONFIG_HOTPLUG_CPU=y
> --
> 2.34.1
>
>
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv


Reviewed-by: Atish Patra <atishp@rivosinc.com>
Damien Le Moal May 22, 2022, 8:57 a.m. UTC | #2 
On 5/22/22 04:33, Palmer Dabbelt wrote:
> From: Palmer Dabbelt <palmer@rivosinc.com>
> 
> The RISC-V port has collected a handful of options that are
> fundamentally non-portable.  To prevent users from shooting themselves
> in the foot, hide them all behind a config entry that explicitly calls
> out that non-portable binaries may be produced.
> 
> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Guo Ren May 22, 2022, 12:27 p.m. UTC | #3 
Reviewed-by: Guo Ren <guoren@kernel.org>

On Sun, May 22, 2022 at 4:46 AM Palmer Dabbelt <palmer@rivosinc.com> wrote:
>
> From: Palmer Dabbelt <palmer@rivosinc.com>
>
> The RISC-V port has collected a handful of options that are
> fundamentally non-portable.  To prevent users from shooting themselves
> in the foot, hide them all behind a config entry that explicitly calls
> out that non-portable binaries may be produced.
>
> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
> ---
> Changes since v2:
>
> * Update the nommu and rv32 defconfigs.  I'm still getting some ugliness
>   like
>
>     $ make.riscv rv32_defconfig
>     *** Default configuration is based on 'defconfig'
>     #
>     # configuration written to .config
>     #
>     Using .config as base
>     Merging ./arch/riscv/configs/32-bit.config
>     Value of CONFIG_PORTABLE is redefined by fragment ./arch/riscv/configs/32-bit.config:
>     Previous value: CONFIG_PORTABLE=y
>     New value: # CONFIG_PORTABLE is not set
>
>     Value of CONFIG_NONPORTABLE is redefined by fragment ./arch/riscv/configs/32-bit.config:
>     Previous value: # CONFIG_NONPORTABLE is not set
>     New value: CONFIG_NONPORTABLE=y
>
>     #
>     # merged configuration written to .config (needs make)
>     #
>     .config:3831:warning: override: ARCH_RV32I changes choice state
>     #
>     # configuration written to .config
>     #
>
>   not sure if there's a better way to do this.
>
> Changes since v1:
>
> * Fix a bunch of spelling mistakes.
> * Move NONPORTABLE under the "Platform type" sub-heading.
> * Fix the rv32i dependency.
>
> ---
>  arch/riscv/Kconfig                            | 28 +++++++++++++++++--
>  arch/riscv/configs/32-bit.config              |  2 ++
>  arch/riscv/configs/nommu_k210_defconfig       |  1 +
>  .../riscv/configs/nommu_k210_sdcard_defconfig |  1 +
>  arch/riscv/configs/nommu_virt_defconfig       |  1 +
>  arch/riscv/configs/rv32_defconfig             |  1 +
>  6 files changed, 32 insertions(+), 2 deletions(-)
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index f863065b478c..cd67b09a80f5 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -222,6 +222,21 @@ source "arch/riscv/Kconfig.erratas"
>
>  menu "Platform type"
>
> +config NONPORTABLE
> +       bool "Allow configurations that result in non-portable kernels"
> +       help
> +         RISC-V kernel binaries are compatible between all known systems
> +         whenever possible, but there are some use cases that can only be
> +         satisfied by configurations that result in kernel binaries that are
> +         not portable between systems.
> +
> +         Selecting N does not guarantee kernels will be portable to all known
> +         systems.  Selecting any of the options guarded by NONPORTABLE will
> +         result in kernel binaries that are unlikely to be portable between
> +         systems.
> +
> +         If unsure, say N.
> +
>  choice
>         prompt "Base ISA"
>         default ARCH_RV64I
> @@ -231,6 +246,7 @@ choice
>
>  config ARCH_RV32I
>         bool "RV32I"
> +       depends on NONPORTABLE
>         select 32BIT
>         select GENERIC_LIB_ASHLDI3
>         select GENERIC_LIB_ASHRDI3
> @@ -541,6 +557,7 @@ config STACKPROTECTOR_PER_TASK
>
>  config PHYS_RAM_BASE_FIXED
>         bool "Explicitly specified physical RAM address"
> +       depends on NONPORTABLE
>         default n
>
>  config PHYS_RAM_BASE
> @@ -554,7 +571,7 @@ config PHYS_RAM_BASE
>
>  config XIP_KERNEL
>         bool "Kernel Execute-In-Place from ROM"
> -       depends on MMU && SPARSEMEM
> +       depends on MMU && SPARSEMEM && NONPORTABLE
>         # This prevents XIP from being enabled by all{yes,mod}config, which
>         # fail to build since XIP doesn't support large kernels.
>         depends on !COMPILE_TEST
> @@ -594,9 +611,16 @@ endmenu
>
>  config BUILTIN_DTB
>         bool
> -       depends on OF
> +       depends on OF && NONPORTABLE
>         default y if XIP_KERNEL
>
> +config PORTABLE
> +       bool
> +       default !NONPORTABLE
> +       select EFI
> +       select OF
> +       select MMU
> +
>  menu "Power management options"
>
>  source "kernel/power/Kconfig"
> diff --git a/arch/riscv/configs/32-bit.config b/arch/riscv/configs/32-bit.config
> index 43f41323b67e..f6af0f708df4 100644
> --- a/arch/riscv/configs/32-bit.config
> +++ b/arch/riscv/configs/32-bit.config
> @@ -1,2 +1,4 @@
>  CONFIG_ARCH_RV32I=y
>  CONFIG_32BIT=y
> +# CONFIG_PORTABLE is not set
> +CONFIG_NONPORTABLE=y
> diff --git a/arch/riscv/configs/nommu_k210_defconfig b/arch/riscv/configs/nommu_k210_defconfig
> index 2438fa39f8ae..96fe8def644c 100644
> --- a/arch/riscv/configs/nommu_k210_defconfig
> +++ b/arch/riscv/configs/nommu_k210_defconfig
> @@ -28,6 +28,7 @@ CONFIG_EMBEDDED=y
>  CONFIG_SLOB=y
>  # CONFIG_MMU is not set
>  CONFIG_SOC_CANAAN=y
> +CONFIG_NONPORTABLE=y
>  CONFIG_SMP=y
>  CONFIG_NR_CPUS=2
>  CONFIG_CMDLINE="earlycon console=ttySIF0"
> diff --git a/arch/riscv/configs/nommu_k210_sdcard_defconfig b/arch/riscv/configs/nommu_k210_sdcard_defconfig
> index 9a133e63ae5b..379740654373 100644
> --- a/arch/riscv/configs/nommu_k210_sdcard_defconfig
> +++ b/arch/riscv/configs/nommu_k210_sdcard_defconfig
> @@ -20,6 +20,7 @@ CONFIG_EMBEDDED=y
>  CONFIG_SLOB=y
>  # CONFIG_MMU is not set
>  CONFIG_SOC_CANAAN=y
> +CONFIG_NONPORTABLE=y
>  CONFIG_SMP=y
>  CONFIG_NR_CPUS=2
>  CONFIG_CMDLINE="earlycon console=ttySIF0 root=/dev/mmcblk0p1 rootwait ro"
> diff --git a/arch/riscv/configs/nommu_virt_defconfig b/arch/riscv/configs/nommu_virt_defconfig
> index 5269fbb6b4fc..1a56eda5ce46 100644
> --- a/arch/riscv/configs/nommu_virt_defconfig
> +++ b/arch/riscv/configs/nommu_virt_defconfig
> @@ -25,6 +25,7 @@ CONFIG_EXPERT=y
>  CONFIG_SLOB=y
>  # CONFIG_MMU is not set
>  CONFIG_SOC_VIRT=y
> +CONFIG_NONPORTABLE=y
>  CONFIG_SMP=y
>  CONFIG_CMDLINE="root=/dev/vda rw earlycon=uart8250,mmio,0x10000000,115200n8 console=ttyS0"
>  CONFIG_CMDLINE_FORCE=y
> diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig
> index 7e5efdc3829d..77bdb1d05a88 100644
> --- a/arch/riscv/configs/rv32_defconfig
> +++ b/arch/riscv/configs/rv32_defconfig
> @@ -18,6 +18,7 @@ CONFIG_EXPERT=y
>  CONFIG_PROFILING=y
>  CONFIG_SOC_SIFIVE=y
>  CONFIG_SOC_VIRT=y
> +CONFIG_NONPORTABLE=y
>  CONFIG_ARCH_RV32I=y
>  CONFIG_SMP=y
>  CONFIG_HOTPLUG_CPU=y
> --
> 2.34.1
>
Palmer Dabbelt July 14, 2022, 9:26 p.m. UTC | #4 
On Sat, 21 May 2022 12:33:57 PDT (-0700), Palmer Dabbelt wrote:
> From: Palmer Dabbelt <palmer@rivosinc.com>
>
> The RISC-V port has collected a handful of options that are
> fundamentally non-portable.  To prevent users from shooting themselves
> in the foot, hide them all behind a config entry that explicitly calls
> out that non-portable binaries may be produced.
>
> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
> ---
> Changes since v2:
>
> * Update the nommu and rv32 defconfigs.  I'm still getting some ugliness
>   like
>
>     $ make.riscv rv32_defconfig
>     *** Default configuration is based on 'defconfig'
>     #
>     # configuration written to .config
>     #
>     Using .config as base
>     Merging ./arch/riscv/configs/32-bit.config
>     Value of CONFIG_PORTABLE is redefined by fragment ./arch/riscv/configs/32-bit.config:
>     Previous value: CONFIG_PORTABLE=y
>     New value: # CONFIG_PORTABLE is not set
>
>     Value of CONFIG_NONPORTABLE is redefined by fragment ./arch/riscv/configs/32-bit.config:
>     Previous value: # CONFIG_NONPORTABLE is not set
>     New value: CONFIG_NONPORTABLE=y
>
>     #
>     # merged configuration written to .config (needs make)
>     #
>     .config:3831:warning: override: ARCH_RV32I changes choice state
>     #
>     # configuration written to .config
>     #
>
>   not sure if there's a better way to do this.
>
> Changes since v1:
>
> * Fix a bunch of spelling mistakes.
> * Move NONPORTABLE under the "Platform type" sub-heading.
> * Fix the rv32i dependency.
>
> ---
>  arch/riscv/Kconfig                            | 28 +++++++++++++++++--
>  arch/riscv/configs/32-bit.config              |  2 ++
>  arch/riscv/configs/nommu_k210_defconfig       |  1 +
>  .../riscv/configs/nommu_k210_sdcard_defconfig |  1 +
>  arch/riscv/configs/nommu_virt_defconfig       |  1 +
>  arch/riscv/configs/rv32_defconfig             |  1 +
>  6 files changed, 32 insertions(+), 2 deletions(-)
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index f863065b478c..cd67b09a80f5 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -222,6 +222,21 @@ source "arch/riscv/Kconfig.erratas"
>
>  menu "Platform type"
>
> +config NONPORTABLE
> +	bool "Allow configurations that result in non-portable kernels"
> +	help
> +	  RISC-V kernel binaries are compatible between all known systems
> +	  whenever possible, but there are some use cases that can only be
> +	  satisfied by configurations that result in kernel binaries that are
> +	  not portable between systems.
> +
> +	  Selecting N does not guarantee kernels will be portable to all known
> +	  systems.  Selecting any of the options guarded by NONPORTABLE will
> +	  result in kernel binaries that are unlikely to be portable between
> +	  systems.
> +
> +	  If unsure, say N.
> +
>  choice
>  	prompt "Base ISA"
>  	default ARCH_RV64I
> @@ -231,6 +246,7 @@ choice
>
>  config ARCH_RV32I
>  	bool "RV32I"
> +	depends on NONPORTABLE
>  	select 32BIT
>  	select GENERIC_LIB_ASHLDI3
>  	select GENERIC_LIB_ASHRDI3
> @@ -541,6 +557,7 @@ config STACKPROTECTOR_PER_TASK
>
>  config PHYS_RAM_BASE_FIXED
>  	bool "Explicitly specified physical RAM address"
> +	depends on NONPORTABLE
>  	default n
>
>  config PHYS_RAM_BASE
> @@ -554,7 +571,7 @@ config PHYS_RAM_BASE
>
>  config XIP_KERNEL
>  	bool "Kernel Execute-In-Place from ROM"
> -	depends on MMU && SPARSEMEM
> +	depends on MMU && SPARSEMEM && NONPORTABLE
>  	# This prevents XIP from being enabled by all{yes,mod}config, which
>  	# fail to build since XIP doesn't support large kernels.
>  	depends on !COMPILE_TEST
> @@ -594,9 +611,16 @@ endmenu
>
>  config BUILTIN_DTB
>  	bool
> -	depends on OF
> +	depends on OF && NONPORTABLE
>  	default y if XIP_KERNEL
>
> +config PORTABLE
> +	bool
> +	default !NONPORTABLE
> +	select EFI
> +	select OF
> +	select MMU
> +
>  menu "Power management options"
>
>  source "kernel/power/Kconfig"
> diff --git a/arch/riscv/configs/32-bit.config b/arch/riscv/configs/32-bit.config
> index 43f41323b67e..f6af0f708df4 100644
> --- a/arch/riscv/configs/32-bit.config
> +++ b/arch/riscv/configs/32-bit.config
> @@ -1,2 +1,4 @@
>  CONFIG_ARCH_RV32I=y
>  CONFIG_32BIT=y
> +# CONFIG_PORTABLE is not set
> +CONFIG_NONPORTABLE=y
> diff --git a/arch/riscv/configs/nommu_k210_defconfig b/arch/riscv/configs/nommu_k210_defconfig
> index 2438fa39f8ae..96fe8def644c 100644
> --- a/arch/riscv/configs/nommu_k210_defconfig
> +++ b/arch/riscv/configs/nommu_k210_defconfig
> @@ -28,6 +28,7 @@ CONFIG_EMBEDDED=y
>  CONFIG_SLOB=y
>  # CONFIG_MMU is not set
>  CONFIG_SOC_CANAAN=y
> +CONFIG_NONPORTABLE=y
>  CONFIG_SMP=y
>  CONFIG_NR_CPUS=2
>  CONFIG_CMDLINE="earlycon console=ttySIF0"
> diff --git a/arch/riscv/configs/nommu_k210_sdcard_defconfig b/arch/riscv/configs/nommu_k210_sdcard_defconfig
> index 9a133e63ae5b..379740654373 100644
> --- a/arch/riscv/configs/nommu_k210_sdcard_defconfig
> +++ b/arch/riscv/configs/nommu_k210_sdcard_defconfig
> @@ -20,6 +20,7 @@ CONFIG_EMBEDDED=y
>  CONFIG_SLOB=y
>  # CONFIG_MMU is not set
>  CONFIG_SOC_CANAAN=y
> +CONFIG_NONPORTABLE=y
>  CONFIG_SMP=y
>  CONFIG_NR_CPUS=2
>  CONFIG_CMDLINE="earlycon console=ttySIF0 root=/dev/mmcblk0p1 rootwait ro"
> diff --git a/arch/riscv/configs/nommu_virt_defconfig b/arch/riscv/configs/nommu_virt_defconfig
> index 5269fbb6b4fc..1a56eda5ce46 100644
> --- a/arch/riscv/configs/nommu_virt_defconfig
> +++ b/arch/riscv/configs/nommu_virt_defconfig
> @@ -25,6 +25,7 @@ CONFIG_EXPERT=y
>  CONFIG_SLOB=y
>  # CONFIG_MMU is not set
>  CONFIG_SOC_VIRT=y
> +CONFIG_NONPORTABLE=y
>  CONFIG_SMP=y
>  CONFIG_CMDLINE="root=/dev/vda rw earlycon=uart8250,mmio,0x10000000,115200n8 console=ttyS0"
>  CONFIG_CMDLINE_FORCE=y
> diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig
> index 7e5efdc3829d..77bdb1d05a88 100644
> --- a/arch/riscv/configs/rv32_defconfig
> +++ b/arch/riscv/configs/rv32_defconfig
> @@ -18,6 +18,7 @@ CONFIG_EXPERT=y
>  CONFIG_PROFILING=y
>  CONFIG_SOC_SIFIVE=y
>  CONFIG_SOC_VIRT=y
> +CONFIG_NONPORTABLE=y
>  CONFIG_ARCH_RV32I=y
>  CONFIG_SMP=y
>  CONFIG_HOTPLUG_CPU=y

This is on for-next.
Geert Uytterhoeven July 15, 2022, 7:47 a.m. UTC | #5 
Hi Palmer,

On Sat, May 21, 2022 at 10:49 PM Palmer Dabbelt <palmer@rivosinc.com> wrote:
> From: Palmer Dabbelt <palmer@rivosinc.com>
>
> The RISC-V port has collected a handful of options that are
> fundamentally non-portable.  To prevent users from shooting themselves
> in the foot, hide them all behind a config entry that explicitly calls
> out that non-portable binaries may be produced.
>
> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

Thanks for your patch, which is now commit 44c1e84a38a03175 ("RISC-V:
Add CONFIG_{NON,}PORTABLE") in riscv/for-next

> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -222,6 +222,21 @@ source "arch/riscv/Kconfig.erratas"
>
>  menu "Platform type"
>
> +config NONPORTABLE
> +       bool "Allow configurations that result in non-portable kernels"
> +       help
> +         RISC-V kernel binaries are compatible between all known systems
> +         whenever possible, but there are some use cases that can only be
> +         satisfied by configurations that result in kernel binaries that are
> +         not portable between systems.
> +
> +         Selecting N does not guarantee kernels will be portable to all known
> +         systems.  Selecting any of the options guarded by NONPORTABLE will
> +         result in kernel binaries that are unlikely to be portable between
> +         systems.
> +
> +         If unsure, say N.

Doing it this way means allmodconfig will enable NONPORTABLE, which
may not be what we want?

> +
>  choice
>         prompt "Base ISA"
>         default ARCH_RV64I

> @@ -554,7 +571,7 @@ config PHYS_RAM_BASE
>
>  config XIP_KERNEL
>         bool "Kernel Execute-In-Place from ROM"
> -       depends on MMU && SPARSEMEM
> +       depends on MMU && SPARSEMEM && NONPORTABLE

Nice! Would we get something like this on arm32 past rmk?

>         # This prevents XIP from being enabled by all{yes,mod}config, which
>         # fail to build since XIP doesn't support large kernels.
>         depends on !COMPILE_TEST
> @@ -594,9 +611,16 @@ endmenu
>
>  config BUILTIN_DTB
>         bool
> -       depends on OF
> +       depends on OF && NONPORTABLE
>         default y if XIP_KERNEL
>
> +config PORTABLE
> +       bool
> +       default !NONPORTABLE
> +       select EFI
> +       select OF
> +       select MMU
> +
>  menu "Power management options"
>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
diff mbox series

Patch

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index f863065b478c..cd67b09a80f5 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -222,6 +222,21 @@  source "arch/riscv/Kconfig.erratas"
 
 menu "Platform type"
 
+config NONPORTABLE
+	bool "Allow configurations that result in non-portable kernels"
+	help
+	  RISC-V kernel binaries are compatible between all known systems
+	  whenever possible, but there are some use cases that can only be
+	  satisfied by configurations that result in kernel binaries that are
+	  not portable between systems.
+
+	  Selecting N does not guarantee kernels will be portable to all known
+	  systems.  Selecting any of the options guarded by NONPORTABLE will
+	  result in kernel binaries that are unlikely to be portable between
+	  systems.
+
+	  If unsure, say N.
+
 choice
 	prompt "Base ISA"
 	default ARCH_RV64I
@@ -231,6 +246,7 @@  choice
 
 config ARCH_RV32I
 	bool "RV32I"
+	depends on NONPORTABLE
 	select 32BIT
 	select GENERIC_LIB_ASHLDI3
 	select GENERIC_LIB_ASHRDI3
@@ -541,6 +557,7 @@  config STACKPROTECTOR_PER_TASK
 
 config PHYS_RAM_BASE_FIXED
 	bool "Explicitly specified physical RAM address"
+	depends on NONPORTABLE
 	default n
 
 config PHYS_RAM_BASE
@@ -554,7 +571,7 @@  config PHYS_RAM_BASE
 
 config XIP_KERNEL
 	bool "Kernel Execute-In-Place from ROM"
-	depends on MMU && SPARSEMEM
+	depends on MMU && SPARSEMEM && NONPORTABLE
 	# This prevents XIP from being enabled by all{yes,mod}config, which
 	# fail to build since XIP doesn't support large kernels.
 	depends on !COMPILE_TEST
@@ -594,9 +611,16 @@  endmenu
 
 config BUILTIN_DTB
 	bool
-	depends on OF
+	depends on OF && NONPORTABLE
 	default y if XIP_KERNEL
 
+config PORTABLE
+	bool
+	default !NONPORTABLE
+	select EFI
+	select OF
+	select MMU
+
 menu "Power management options"
 
 source "kernel/power/Kconfig"
diff --git a/arch/riscv/configs/32-bit.config b/arch/riscv/configs/32-bit.config
index 43f41323b67e..f6af0f708df4 100644
--- a/arch/riscv/configs/32-bit.config
+++ b/arch/riscv/configs/32-bit.config
@@ -1,2 +1,4 @@ 
 CONFIG_ARCH_RV32I=y
 CONFIG_32BIT=y
+# CONFIG_PORTABLE is not set
+CONFIG_NONPORTABLE=y
diff --git a/arch/riscv/configs/nommu_k210_defconfig b/arch/riscv/configs/nommu_k210_defconfig
index 2438fa39f8ae..96fe8def644c 100644
--- a/arch/riscv/configs/nommu_k210_defconfig
+++ b/arch/riscv/configs/nommu_k210_defconfig
@@ -28,6 +28,7 @@  CONFIG_EMBEDDED=y
 CONFIG_SLOB=y
 # CONFIG_MMU is not set
 CONFIG_SOC_CANAAN=y
+CONFIG_NONPORTABLE=y
 CONFIG_SMP=y
 CONFIG_NR_CPUS=2
 CONFIG_CMDLINE="earlycon console=ttySIF0"
diff --git a/arch/riscv/configs/nommu_k210_sdcard_defconfig b/arch/riscv/configs/nommu_k210_sdcard_defconfig
index 9a133e63ae5b..379740654373 100644
--- a/arch/riscv/configs/nommu_k210_sdcard_defconfig
+++ b/arch/riscv/configs/nommu_k210_sdcard_defconfig
@@ -20,6 +20,7 @@  CONFIG_EMBEDDED=y
 CONFIG_SLOB=y
 # CONFIG_MMU is not set
 CONFIG_SOC_CANAAN=y
+CONFIG_NONPORTABLE=y
 CONFIG_SMP=y
 CONFIG_NR_CPUS=2
 CONFIG_CMDLINE="earlycon console=ttySIF0 root=/dev/mmcblk0p1 rootwait ro"
diff --git a/arch/riscv/configs/nommu_virt_defconfig b/arch/riscv/configs/nommu_virt_defconfig
index 5269fbb6b4fc..1a56eda5ce46 100644
--- a/arch/riscv/configs/nommu_virt_defconfig
+++ b/arch/riscv/configs/nommu_virt_defconfig
@@ -25,6 +25,7 @@  CONFIG_EXPERT=y
 CONFIG_SLOB=y
 # CONFIG_MMU is not set
 CONFIG_SOC_VIRT=y
+CONFIG_NONPORTABLE=y
 CONFIG_SMP=y
 CONFIG_CMDLINE="root=/dev/vda rw earlycon=uart8250,mmio,0x10000000,115200n8 console=ttyS0"
 CONFIG_CMDLINE_FORCE=y
diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig
index 7e5efdc3829d..77bdb1d05a88 100644
--- a/arch/riscv/configs/rv32_defconfig
+++ b/arch/riscv/configs/rv32_defconfig
@@ -18,6 +18,7 @@  CONFIG_EXPERT=y
 CONFIG_PROFILING=y
 CONFIG_SOC_SIFIVE=y
 CONFIG_SOC_VIRT=y
+CONFIG_NONPORTABLE=y
 CONFIG_ARCH_RV32I=y
 CONFIG_SMP=y
 CONFIG_HOTPLUG_CPU=y