diff mbox series

[06/12] arch: Declare screen_info in <asm/screen_info.h>

Message ID 20230629121952.10559-7-tzimmermann@suse.de
State New
Headers show
Series arch,fbdev: Move screen_info into arch/ | expand

Commit Message

Thomas Zimmermann June 29, 2023, 11:45 a.m. UTC 
The variable screen_info does not exist on all architectures. Declare
it in <asm-generic/screen_info.h>. All architectures that do declare it
will provide it via <asm/screen_info.h>.

Add the Kconfig token ARCH_HAS_SCREEN_INFO to guard against access on
architectures that don't provide screen_info.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Juerg Haefliger <juerg.haefliger@canonical.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Niklas Schnelle <schnelle@linux.ibm.com>
Cc: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Sebastian Reichel <sebastian.reichel@collabora.com>
Cc: "Mike Rapoport (IBM)" <rppt@kernel.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Zi Yan <ziy@nvidia.com>
---
 arch/Kconfig                      |  6 ++++++
 arch/alpha/Kconfig                |  1 +
 arch/arm/Kconfig                  |  1 +
 arch/arm64/Kconfig                |  1 +
 arch/csky/Kconfig                 |  1 +
 arch/hexagon/Kconfig              |  1 +
 arch/ia64/Kconfig                 |  1 +
 arch/loongarch/Kconfig            |  1 +
 arch/mips/Kconfig                 |  1 +
 arch/nios2/Kconfig                |  1 +
 arch/powerpc/Kconfig              |  1 +
 arch/riscv/Kconfig                |  1 +
 arch/sh/Kconfig                   |  1 +
 arch/sparc/Kconfig                |  1 +
 arch/x86/Kconfig                  |  1 +
 arch/xtensa/Kconfig               |  1 +
 drivers/video/Kconfig             |  3 +++
 include/asm-generic/Kbuild        |  1 +
 include/asm-generic/screen_info.h | 12 ++++++++++++
 include/linux/screen_info.h       |  2 +-
 20 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 include/asm-generic/screen_info.h

Comments

WANG Xuerui June 29, 2023, 12:55 p.m. UTC | #1 
On 2023/6/29 19:45, Thomas Zimmermann wrote:
> The variable screen_info does not exist on all architectures. Declare
> it in <asm-generic/screen_info.h>. All architectures that do declare it
> will provide it via <asm/screen_info.h>.
> 
> Add the Kconfig token ARCH_HAS_SCREEN_INFO to guard against access on
> architectures that don't provide screen_info.
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> Cc: Richard Henderson <richard.henderson@linaro.org>
> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
> Cc: Matt Turner <mattst88@gmail.com>
> Cc: Russell King <linux@armlinux.org.uk>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will@kernel.org>
> Cc: Guo Ren <guoren@kernel.org>
> Cc: Brian Cain <bcain@quicinc.com>
> Cc: Huacai Chen <chenhuacai@kernel.org>
> Cc: WANG Xuerui <kernel@xen0n.name>
> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
> Cc: Dinh Nguyen <dinguyen@kernel.org>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Nicholas Piggin <npiggin@gmail.com>
> Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
> Cc: Paul Walmsley <paul.walmsley@sifive.com>
> Cc: Palmer Dabbelt <palmer@dabbelt.com>
> Cc: Albert Ou <aou@eecs.berkeley.edu>
> Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
> Cc: Rich Felker <dalias@libc.org>
> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: Dave Hansen <dave.hansen@linux.intel.com>
> Cc: x86@kernel.org
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Cc: Chris Zankel <chris@zankel.net>
> Cc: Max Filippov <jcmvbkbc@gmail.com>
> Cc: Helge Deller <deller@gmx.de>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: "Paul E. McKenney" <paulmck@kernel.org>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Frederic Weisbecker <frederic@kernel.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Ard Biesheuvel <ardb@kernel.org>
> Cc: Sami Tolvanen <samitolvanen@google.com>
> Cc: Juerg Haefliger <juerg.haefliger@canonical.com>
> Cc: Geert Uytterhoeven <geert@linux-m68k.org>
> Cc: Anshuman Khandual <anshuman.khandual@arm.com>
> Cc: Niklas Schnelle <schnelle@linux.ibm.com>
> Cc: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Cc: Sebastian Reichel <sebastian.reichel@collabora.com>
> Cc: "Mike Rapoport (IBM)" <rppt@kernel.org>
> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
> Cc: Zi Yan <ziy@nvidia.com>
> ---
>   arch/Kconfig                      |  6 ++++++
>   arch/alpha/Kconfig                |  1 +
>   arch/arm/Kconfig                  |  1 +
>   arch/arm64/Kconfig                |  1 +
>   arch/csky/Kconfig                 |  1 +
>   arch/hexagon/Kconfig              |  1 +
>   arch/ia64/Kconfig                 |  1 +
>   arch/loongarch/Kconfig            |  1 +
>   arch/mips/Kconfig                 |  1 +
>   arch/nios2/Kconfig                |  1 +
>   arch/powerpc/Kconfig              |  1 +
>   arch/riscv/Kconfig                |  1 +
>   arch/sh/Kconfig                   |  1 +
>   arch/sparc/Kconfig                |  1 +
>   arch/x86/Kconfig                  |  1 +
>   arch/xtensa/Kconfig               |  1 +
>   drivers/video/Kconfig             |  3 +++
>   include/asm-generic/Kbuild        |  1 +
>   include/asm-generic/screen_info.h | 12 ++++++++++++
>   include/linux/screen_info.h       |  2 +-
>   20 files changed, 38 insertions(+), 1 deletion(-)
>   create mode 100644 include/asm-generic/screen_info.h
> 
> diff --git a/arch/Kconfig b/arch/Kconfig
> index 205fd23e0cada..2f58293fd7bcb 100644
> --- a/arch/Kconfig
> +++ b/arch/Kconfig
> @@ -1466,6 +1466,12 @@ config ARCH_HAS_NONLEAF_PMD_YOUNG
>   	  address translations. Page table walkers that clear the accessed bit
>   	  may use this capability to reduce their search space.
>   
> +config ARCH_HAS_SCREEN_INFO
> +	bool
> +	help
> +	  Selected by architectures that provide a global instance of
> +	  screen_info.
> +
>   source "kernel/gcov/Kconfig"
>   
>   source "scripts/gcc-plugins/Kconfig"
> [snip]
> diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
> index d38b066fc931b..6aab2fb7753da 100644
> --- a/arch/loongarch/Kconfig
> +++ b/arch/loongarch/Kconfig
> @@ -13,6 +13,7 @@ config LOONGARCH
>   	select ARCH_HAS_FORTIFY_SOURCE
>   	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
>   	select ARCH_HAS_PTE_SPECIAL
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
>   	select ARCH_INLINE_READ_LOCK if !PREEMPTION
>   	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
> [snip]

Acked-by: WANG Xuerui <git@xen0n.name> # loongarch

Thanks!
Arnd Bergmann June 29, 2023, 1:03 p.m. UTC | #2 
On Thu, Jun 29, 2023, at 13:45, Thomas Zimmermann wrote:

> diff --git a/include/asm-generic/screen_info.h 
> b/include/asm-generic/screen_info.h
> new file mode 100644
> index 0000000000000..6fd0e50fabfcd
> --- /dev/null
> +++ b/include/asm-generic/screen_info.h
> @@ -0,0 +1,12 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +
> +#ifndef _ASM_GENERIC_SCREEN_INFO_H
> +#define _ASM_GENERIC_SCREEN_INFO_H
> +
> +#include <uapi/linux/screen_info.h>
> +
> +#if defined(CONFIG_ARCH_HAS_SCREEN_INFO)
> +extern struct screen_info screen_info;
> +#endif
> +
> +#endif /* _ASM_GENERIC_SCREEN_INFO_H */
> diff --git a/include/linux/screen_info.h b/include/linux/screen_info.h
> index eab7081392d50..c764b9a51c24b 100644
> --- a/include/linux/screen_info.h
> +++ b/include/linux/screen_info.h
> @@ -4,6 +4,6 @@
> 
>  #include <uapi/linux/screen_info.h>
> 
> -extern struct screen_info screen_info;
> +#include <asm/screen_info.h>
> 

What is the purpose of adding a file in asm-generic? If all
architectures use the same generic file, I'd just leave the
declaration in include/linux/. I wouldn't bother adding the
#ifdef either, but I can see how that helps turn a link
error into an earlier compile error.

      Arnd
suijingfeng Aug. 18, 2023, 2:04 p.m. UTC | #3 
Hi,


Why this patch get dropped in the end?

Since the global screen_info is an arch-specific thing,
Whenever an arch-neutral module or subsystem references the global screen_info,
There are some complaints from either compile testing robot.
Well, a programmer may handle it by using the CONFIG_SYSFB guard,
but it is not as precise as what this patch provided.

Personally, I think this patch is still valuable.
I suggest either forcing all other architectures to export screen_info,
like the X86 and IA64 arch does, after all the screen_info is a good thing.
or provide the fine-control version like this patch does.


On 2023/6/29 19:45, Thomas Zimmermann wrote:
> The variable screen_info does not exist on all architectures. Declare
> it in <asm-generic/screen_info.h>. All architectures that do declare it
> will provide it via <asm/screen_info.h>.
>
> Add the Kconfig token ARCH_HAS_SCREEN_INFO to guard against access on
> architectures that don't provide screen_info.
>
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> Cc: Richard Henderson <richard.henderson@linaro.org>
> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
> Cc: Matt Turner <mattst88@gmail.com>
> Cc: Russell King <linux@armlinux.org.uk>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will@kernel.org>
> Cc: Guo Ren <guoren@kernel.org>
> Cc: Brian Cain <bcain@quicinc.com>
> Cc: Huacai Chen <chenhuacai@kernel.org>
> Cc: WANG Xuerui <kernel@xen0n.name>
> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
> Cc: Dinh Nguyen <dinguyen@kernel.org>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Nicholas Piggin <npiggin@gmail.com>
> Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
> Cc: Paul Walmsley <paul.walmsley@sifive.com>
> Cc: Palmer Dabbelt <palmer@dabbelt.com>
> Cc: Albert Ou <aou@eecs.berkeley.edu>
> Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
> Cc: Rich Felker <dalias@libc.org>
> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: Dave Hansen <dave.hansen@linux.intel.com>
> Cc: x86@kernel.org
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Cc: Chris Zankel <chris@zankel.net>
> Cc: Max Filippov <jcmvbkbc@gmail.com>
> Cc: Helge Deller <deller@gmx.de>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: "Paul E. McKenney" <paulmck@kernel.org>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Frederic Weisbecker <frederic@kernel.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Ard Biesheuvel <ardb@kernel.org>
> Cc: Sami Tolvanen <samitolvanen@google.com>
> Cc: Juerg Haefliger <juerg.haefliger@canonical.com>
> Cc: Geert Uytterhoeven <geert@linux-m68k.org>
> Cc: Anshuman Khandual <anshuman.khandual@arm.com>
> Cc: Niklas Schnelle <schnelle@linux.ibm.com>
> Cc: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Cc: Sebastian Reichel <sebastian.reichel@collabora.com>
> Cc: "Mike Rapoport (IBM)" <rppt@kernel.org>
> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
> Cc: Zi Yan <ziy@nvidia.com>
> Acked-by: WANG Xuerui <git@xen0n.name> # loongarch
> ---
>   arch/Kconfig                      |  6 ++++++
>   arch/alpha/Kconfig                |  1 +
>   arch/arm/Kconfig                  |  1 +
>   arch/arm64/Kconfig                |  1 +
>   arch/csky/Kconfig                 |  1 +
>   arch/hexagon/Kconfig              |  1 +
>   arch/ia64/Kconfig                 |  1 +
>   arch/loongarch/Kconfig            |  1 +
>   arch/mips/Kconfig                 |  1 +
>   arch/nios2/Kconfig                |  1 +
>   arch/powerpc/Kconfig              |  1 +
>   arch/riscv/Kconfig                |  1 +
>   arch/sh/Kconfig                   |  1 +
>   arch/sparc/Kconfig                |  1 +
>   arch/x86/Kconfig                  |  1 +
>   arch/xtensa/Kconfig               |  1 +
>   drivers/video/Kconfig             |  3 +++
>   include/asm-generic/Kbuild        |  1 +
>   include/asm-generic/screen_info.h | 12 ++++++++++++
>   include/linux/screen_info.h       |  2 +-
>   20 files changed, 38 insertions(+), 1 deletion(-)
>   create mode 100644 include/asm-generic/screen_info.h
>
> diff --git a/arch/Kconfig b/arch/Kconfig
> index 205fd23e0cada..2f58293fd7bcb 100644
> --- a/arch/Kconfig
> +++ b/arch/Kconfig
> @@ -1466,6 +1466,12 @@ config ARCH_HAS_NONLEAF_PMD_YOUNG
>   	  address translations. Page table walkers that clear the accessed bit
>   	  may use this capability to reduce their search space.
>   
> +config ARCH_HAS_SCREEN_INFO
> +	bool
> +	help
> +	  Selected by architectures that provide a global instance of
> +	  screen_info.
> +
>   source "kernel/gcov/Kconfig"
>   
>   source "scripts/gcc-plugins/Kconfig"
> diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
> index a5c2b1aa46b02..d749011d88b14 100644
> --- a/arch/alpha/Kconfig
> +++ b/arch/alpha/Kconfig
> @@ -4,6 +4,7 @@ config ALPHA
>   	default y
>   	select ARCH_32BIT_USTAT_F_TINODE
>   	select ARCH_HAS_CURRENT_STACK_POINTER
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_MIGHT_HAVE_PC_PARPORT
>   	select ARCH_MIGHT_HAVE_PC_SERIO
>   	select ARCH_NO_PREEMPT
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 0fb4b218f6658..a9d01ee67a90e 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -15,6 +15,7 @@ config ARM
>   	select ARCH_HAS_MEMBARRIER_SYNC_CORE
>   	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
>   	select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_SETUP_DMA_OPS
>   	select ARCH_HAS_SET_MEMORY
>   	select ARCH_STACKWALK
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 343e1e1cae10a..21addc4715bb3 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -36,6 +36,7 @@ config ARM64
>   	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
>   	select ARCH_HAS_PTE_DEVMAP
>   	select ARCH_HAS_PTE_SPECIAL
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_SETUP_DMA_OPS
>   	select ARCH_HAS_SET_DIRECT_MAP
>   	select ARCH_HAS_SET_MEMORY
> diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
> index 4df1f8c9d170b..28444e581fc1f 100644
> --- a/arch/csky/Kconfig
> +++ b/arch/csky/Kconfig
> @@ -10,6 +10,7 @@ config CSKY
>   	select ARCH_USE_QUEUED_RWLOCKS
>   	select ARCH_USE_QUEUED_SPINLOCKS
>   	select ARCH_HAS_CURRENT_STACK_POINTER
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_INLINE_READ_LOCK if !PREEMPTION
>   	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
>   	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
> diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig
> index 54eadf2651786..cc683c0a43d34 100644
> --- a/arch/hexagon/Kconfig
> +++ b/arch/hexagon/Kconfig
> @@ -5,6 +5,7 @@ comment "Linux Kernel Configuration for Hexagon"
>   config HEXAGON
>   	def_bool y
>   	select ARCH_32BIT_OFF_T
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
>   	select ARCH_NO_PREEMPT
>   	select DMA_GLOBAL_POOL
> diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
> index e79f15e32a451..8b1e785e6d53d 100644
> --- a/arch/ia64/Kconfig
> +++ b/arch/ia64/Kconfig
> @@ -10,6 +10,7 @@ config IA64
>   	bool
>   	select ARCH_BINFMT_ELF_EXTRA_PHDRS
>   	select ARCH_HAS_DMA_MARK_CLEAN
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_STRNCPY_FROM_USER
>   	select ARCH_HAS_STRNLEN_USER
>   	select ARCH_MIGHT_HAVE_PC_PARPORT
> diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
> index d38b066fc931b..6aab2fb7753da 100644
> --- a/arch/loongarch/Kconfig
> +++ b/arch/loongarch/Kconfig
> @@ -13,6 +13,7 @@ config LOONGARCH
>   	select ARCH_HAS_FORTIFY_SOURCE
>   	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
>   	select ARCH_HAS_PTE_SPECIAL
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
>   	select ARCH_INLINE_READ_LOCK if !PREEMPTION
>   	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
> index 675a8660cb85a..c0ae09789cb6d 100644
> --- a/arch/mips/Kconfig
> +++ b/arch/mips/Kconfig
> @@ -10,6 +10,7 @@ config MIPS
>   	select ARCH_HAS_KCOV
>   	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE if !EVA
>   	select ARCH_HAS_PTE_SPECIAL if !(32BIT && CPU_HAS_RIXI)
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_STRNCPY_FROM_USER
>   	select ARCH_HAS_STRNLEN_USER
>   	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
> diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig
> index e5936417d3cd3..7183eea282212 100644
> --- a/arch/nios2/Kconfig
> +++ b/arch/nios2/Kconfig
> @@ -3,6 +3,7 @@ config NIOS2
>   	def_bool y
>   	select ARCH_32BIT_OFF_T
>   	select ARCH_HAS_DMA_PREP_COHERENT
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_SYNC_DMA_FOR_CPU
>   	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
>   	select ARCH_HAS_DMA_SET_UNCACHED
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index bff5820b7cda1..b1acad3076180 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -148,6 +148,7 @@ config PPC
>   	select ARCH_HAS_PTE_DEVMAP		if PPC_BOOK3S_64
>   	select ARCH_HAS_PTE_SPECIAL
>   	select ARCH_HAS_SCALED_CPUTIME		if VIRT_CPU_ACCOUNTING_NATIVE && PPC_BOOK3S_64
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_SET_MEMORY
>   	select ARCH_HAS_STRICT_KERNEL_RWX	if (PPC_BOOK3S || PPC_8xx || 40x) && !HIBERNATION
>   	select ARCH_HAS_STRICT_KERNEL_RWX	if PPC_85xx && !HIBERNATION && !RANDOMIZE_BASE
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 5966ad97c30c3..b5a48f8424af9 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -29,6 +29,7 @@ config RISCV
>   	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
>   	select ARCH_HAS_PMEM_API
>   	select ARCH_HAS_PTE_SPECIAL
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_SET_DIRECT_MAP if MMU
>   	select ARCH_HAS_SET_MEMORY if MMU
>   	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
> diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
> index 04b9550cf0070..001f5149952b4 100644
> --- a/arch/sh/Kconfig
> +++ b/arch/sh/Kconfig
> @@ -10,6 +10,7 @@ config SUPERH
>   	select ARCH_HAS_GIGANTIC_PAGE
>   	select ARCH_HAS_GCOV_PROFILE_ALL
>   	select ARCH_HAS_PTE_SPECIAL
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
>   	select ARCH_HIBERNATION_POSSIBLE if MMU
>   	select ARCH_MIGHT_HAVE_PC_PARPORT
> diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
> index 8535e19062f65..e4bfb80b48cfe 100644
> --- a/arch/sparc/Kconfig
> +++ b/arch/sparc/Kconfig
> @@ -13,6 +13,7 @@ config 64BIT
>   config SPARC
>   	bool
>   	default y
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_MIGHT_HAVE_PC_PARPORT if SPARC64 && PCI
>   	select ARCH_MIGHT_HAVE_PC_SERIO
>   	select DMA_OPS
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 53bab123a8ee4..d7c2bf4ee403d 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -91,6 +91,7 @@ config X86
>   	select ARCH_HAS_NONLEAF_PMD_YOUNG	if PGTABLE_LEVELS > 2
>   	select ARCH_HAS_UACCESS_FLUSHCACHE	if X86_64
>   	select ARCH_HAS_COPY_MC			if X86_64
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_SET_MEMORY
>   	select ARCH_HAS_SET_DIRECT_MAP
>   	select ARCH_HAS_STRICT_KERNEL_RWX
> diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
> index 3c6e5471f025b..c6cbd7459939c 100644
> --- a/arch/xtensa/Kconfig
> +++ b/arch/xtensa/Kconfig
> @@ -8,6 +8,7 @@ config XTENSA
>   	select ARCH_HAS_DMA_PREP_COHERENT if MMU
>   	select ARCH_HAS_GCOV_PROFILE_ALL
>   	select ARCH_HAS_KCOV
> +	select ARCH_HAS_SCREEN_INFO
>   	select ARCH_HAS_SYNC_DMA_FOR_CPU if MMU
>   	select ARCH_HAS_SYNC_DMA_FOR_DEVICE if MMU
>   	select ARCH_HAS_DMA_SET_UNCACHED if MMU
> diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
> index 8b2b9ac37c3df..d4a72bea56be0 100644
> --- a/drivers/video/Kconfig
> +++ b/drivers/video/Kconfig
> @@ -21,6 +21,9 @@ config STI_CORE
>   config VIDEO_CMDLINE
>   	bool
>   
> +config ARCH_HAS_SCREEN_INFO
> +	bool
> +
>   config VIDEO_NOMODESET
>   	bool
>   	default n
> diff --git a/include/asm-generic/Kbuild b/include/asm-generic/Kbuild
> index 941be574bbe00..5e5d4158a4b4b 100644
> --- a/include/asm-generic/Kbuild
> +++ b/include/asm-generic/Kbuild
> @@ -47,6 +47,7 @@ mandatory-y += percpu.h
>   mandatory-y += pgalloc.h
>   mandatory-y += preempt.h
>   mandatory-y += rwonce.h
> +mandatory-y += screen_info.h
>   mandatory-y += sections.h
>   mandatory-y += serial.h
>   mandatory-y += shmparam.h
> diff --git a/include/asm-generic/screen_info.h b/include/asm-generic/screen_info.h
> new file mode 100644
> index 0000000000000..6fd0e50fabfcd
> --- /dev/null
> +++ b/include/asm-generic/screen_info.h
> @@ -0,0 +1,12 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +
> +#ifndef _ASM_GENERIC_SCREEN_INFO_H
> +#define _ASM_GENERIC_SCREEN_INFO_H
> +
> +#include <uapi/linux/screen_info.h>
> +
> +#if defined(CONFIG_ARCH_HAS_SCREEN_INFO)
> +extern struct screen_info screen_info;
> +#endif
> +
> +#endif /* _ASM_GENERIC_SCREEN_INFO_H */
> diff --git a/include/linux/screen_info.h b/include/linux/screen_info.h
> index eab7081392d50..c764b9a51c24b 100644
> --- a/include/linux/screen_info.h
> +++ b/include/linux/screen_info.h
> @@ -4,6 +4,6 @@
>   
>   #include <uapi/linux/screen_info.h>
>   
> -extern struct screen_info screen_info;
> +#include <asm/screen_info.h>
>   
>   #endif /* _SCREEN_INFO_H */
suijingfeng Aug. 18, 2023, 2:18 p.m. UTC | #4 
On 2023/8/18 22:04, suijingfeng wrote:
> Hi,
>
>
> Why this patch get dropped in the end?
>
> Since the global screen_info is an arch-specific thing,
> Whenever an arch-neutral module or subsystem references the global 
> screen_info,
> There are some complaints from either compile testing robot.


There are some complaints from either compile testing robot or domain 
specific reviewers who doubt why you select the CONFIG_SYSFB not 
CONFIG_VT or CONFIG_EFI.


> Well, a programmer may handle it by using the CONFIG_SYSFB guard,
> but it is not as precise as what this patch provided.
>
> Personally, I think this patch is still valuable.
> I suggest either forcing all other architectures to export screen_info,
> like the X86 and IA64 arch does, after all the screen_info is a good 
> thing.
> or provide the fine-control version like this patch does.
>

Because all of the three tokens(CONFIG_SYSFB not CONFIG_VT or CONFIG_EFI.)

have no direct relationship with the global screen_info if an arch is 
not mentioned first.



> On 2023/6/29 19:45, Thomas Zimmermann wrote:
>> The variable screen_info does not exist on all architectures. Declare
>> it in <asm-generic/screen_info.h>. All architectures that do declare it
>> will provide it via <asm/screen_info.h>.
>>
>> Add the Kconfig token ARCH_HAS_SCREEN_INFO to guard against access on
>> architectures that don't provide screen_info.
>>
>> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
>> Cc: Richard Henderson <richard.henderson@linaro.org>
>> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
>> Cc: Matt Turner <mattst88@gmail.com>
>> Cc: Russell King <linux@armlinux.org.uk>
>> Cc: Catalin Marinas <catalin.marinas@arm.com>
>> Cc: Will Deacon <will@kernel.org>
>> Cc: Guo Ren <guoren@kernel.org>
>> Cc: Brian Cain <bcain@quicinc.com>
>> Cc: Huacai Chen <chenhuacai@kernel.org>
>> Cc: WANG Xuerui <kernel@xen0n.name>
>> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
>> Cc: Dinh Nguyen <dinguyen@kernel.org>
>> Cc: Michael Ellerman <mpe@ellerman.id.au>
>> Cc: Nicholas Piggin <npiggin@gmail.com>
>> Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
>> Cc: Paul Walmsley <paul.walmsley@sifive.com>
>> Cc: Palmer Dabbelt <palmer@dabbelt.com>
>> Cc: Albert Ou <aou@eecs.berkeley.edu>
>> Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
>> Cc: Rich Felker <dalias@libc.org>
>> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
>> Cc: "David S. Miller" <davem@davemloft.net>
>> Cc: Thomas Gleixner <tglx@linutronix.de>
>> Cc: Ingo Molnar <mingo@redhat.com>
>> Cc: Borislav Petkov <bp@alien8.de>
>> Cc: Dave Hansen <dave.hansen@linux.intel.com>
>> Cc: x86@kernel.org
>> Cc: "H. Peter Anvin" <hpa@zytor.com>
>> Cc: Chris Zankel <chris@zankel.net>
>> Cc: Max Filippov <jcmvbkbc@gmail.com>
>> Cc: Helge Deller <deller@gmx.de>
>> Cc: Arnd Bergmann <arnd@arndb.de>
>> Cc: Kees Cook <keescook@chromium.org>
>> Cc: "Paul E. McKenney" <paulmck@kernel.org>
>> Cc: Peter Zijlstra <peterz@infradead.org>
>> Cc: Frederic Weisbecker <frederic@kernel.org>
>> Cc: Andrew Morton <akpm@linux-foundation.org>
>> Cc: Ard Biesheuvel <ardb@kernel.org>
>> Cc: Sami Tolvanen <samitolvanen@google.com>
>> Cc: Juerg Haefliger <juerg.haefliger@canonical.com>
>> Cc: Geert Uytterhoeven <geert@linux-m68k.org>
>> Cc: Anshuman Khandual <anshuman.khandual@arm.com>
>> Cc: Niklas Schnelle <schnelle@linux.ibm.com>
>> Cc: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>
>> Cc: Linus Walleij <linus.walleij@linaro.org>
>> Cc: Sebastian Reichel <sebastian.reichel@collabora.com>
>> Cc: "Mike Rapoport (IBM)" <rppt@kernel.org>
>> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
>> Cc: Zi Yan <ziy@nvidia.com>
>> Acked-by: WANG Xuerui <git@xen0n.name> # loongarch
>> ---
>>   arch/Kconfig                      |  6 ++++++
>>   arch/alpha/Kconfig                |  1 +
>>   arch/arm/Kconfig                  |  1 +
>>   arch/arm64/Kconfig                |  1 +
>>   arch/csky/Kconfig                 |  1 +
>>   arch/hexagon/Kconfig              |  1 +
>>   arch/ia64/Kconfig                 |  1 +
>>   arch/loongarch/Kconfig            |  1 +
>>   arch/mips/Kconfig                 |  1 +
>>   arch/nios2/Kconfig                |  1 +
>>   arch/powerpc/Kconfig              |  1 +
>>   arch/riscv/Kconfig                |  1 +
>>   arch/sh/Kconfig                   |  1 +
>>   arch/sparc/Kconfig                |  1 +
>>   arch/x86/Kconfig                  |  1 +
>>   arch/xtensa/Kconfig               |  1 +
>>   drivers/video/Kconfig             |  3 +++
>>   include/asm-generic/Kbuild        |  1 +
>>   include/asm-generic/screen_info.h | 12 ++++++++++++
>>   include/linux/screen_info.h       |  2 +-
>>   20 files changed, 38 insertions(+), 1 deletion(-)
>>   create mode 100644 include/asm-generic/screen_info.h
>>
>> diff --git a/arch/Kconfig b/arch/Kconfig
>> index 205fd23e0cada..2f58293fd7bcb 100644
>> --- a/arch/Kconfig
>> +++ b/arch/Kconfig
>> @@ -1466,6 +1466,12 @@ config ARCH_HAS_NONLEAF_PMD_YOUNG
>>         address translations. Page table walkers that clear the 
>> accessed bit
>>         may use this capability to reduce their search space.
>>   +config ARCH_HAS_SCREEN_INFO
>> +    bool
>> +    help
>> +      Selected by architectures that provide a global instance of
>> +      screen_info.
>> +
>>   source "kernel/gcov/Kconfig"
>>     source "scripts/gcc-plugins/Kconfig"
>> diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
>> index a5c2b1aa46b02..d749011d88b14 100644
>> --- a/arch/alpha/Kconfig
>> +++ b/arch/alpha/Kconfig
>> @@ -4,6 +4,7 @@ config ALPHA
>>       default y
>>       select ARCH_32BIT_USTAT_F_TINODE
>>       select ARCH_HAS_CURRENT_STACK_POINTER
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_MIGHT_HAVE_PC_PARPORT
>>       select ARCH_MIGHT_HAVE_PC_SERIO
>>       select ARCH_NO_PREEMPT
>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
>> index 0fb4b218f6658..a9d01ee67a90e 100644
>> --- a/arch/arm/Kconfig
>> +++ b/arch/arm/Kconfig
>> @@ -15,6 +15,7 @@ config ARM
>>       select ARCH_HAS_MEMBARRIER_SYNC_CORE
>>       select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
>>       select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_HAS_SETUP_DMA_OPS
>>       select ARCH_HAS_SET_MEMORY
>>       select ARCH_STACKWALK
>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>> index 343e1e1cae10a..21addc4715bb3 100644
>> --- a/arch/arm64/Kconfig
>> +++ b/arch/arm64/Kconfig
>> @@ -36,6 +36,7 @@ config ARM64
>>       select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
>>       select ARCH_HAS_PTE_DEVMAP
>>       select ARCH_HAS_PTE_SPECIAL
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_HAS_SETUP_DMA_OPS
>>       select ARCH_HAS_SET_DIRECT_MAP
>>       select ARCH_HAS_SET_MEMORY
>> diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
>> index 4df1f8c9d170b..28444e581fc1f 100644
>> --- a/arch/csky/Kconfig
>> +++ b/arch/csky/Kconfig
>> @@ -10,6 +10,7 @@ config CSKY
>>       select ARCH_USE_QUEUED_RWLOCKS
>>       select ARCH_USE_QUEUED_SPINLOCKS
>>       select ARCH_HAS_CURRENT_STACK_POINTER
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_INLINE_READ_LOCK if !PREEMPTION
>>       select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
>>       select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
>> diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig
>> index 54eadf2651786..cc683c0a43d34 100644
>> --- a/arch/hexagon/Kconfig
>> +++ b/arch/hexagon/Kconfig
>> @@ -5,6 +5,7 @@ comment "Linux Kernel Configuration for Hexagon"
>>   config HEXAGON
>>       def_bool y
>>       select ARCH_32BIT_OFF_T
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_HAS_SYNC_DMA_FOR_DEVICE
>>       select ARCH_NO_PREEMPT
>>       select DMA_GLOBAL_POOL
>> diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
>> index e79f15e32a451..8b1e785e6d53d 100644
>> --- a/arch/ia64/Kconfig
>> +++ b/arch/ia64/Kconfig
>> @@ -10,6 +10,7 @@ config IA64
>>       bool
>>       select ARCH_BINFMT_ELF_EXTRA_PHDRS
>>       select ARCH_HAS_DMA_MARK_CLEAN
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_HAS_STRNCPY_FROM_USER
>>       select ARCH_HAS_STRNLEN_USER
>>       select ARCH_MIGHT_HAVE_PC_PARPORT
>> diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
>> index d38b066fc931b..6aab2fb7753da 100644
>> --- a/arch/loongarch/Kconfig
>> +++ b/arch/loongarch/Kconfig
>> @@ -13,6 +13,7 @@ config LOONGARCH
>>       select ARCH_HAS_FORTIFY_SOURCE
>>       select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
>>       select ARCH_HAS_PTE_SPECIAL
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
>>       select ARCH_INLINE_READ_LOCK if !PREEMPTION
>>       select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
>> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
>> index 675a8660cb85a..c0ae09789cb6d 100644
>> --- a/arch/mips/Kconfig
>> +++ b/arch/mips/Kconfig
>> @@ -10,6 +10,7 @@ config MIPS
>>       select ARCH_HAS_KCOV
>>       select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE if !EVA
>>       select ARCH_HAS_PTE_SPECIAL if !(32BIT && CPU_HAS_RIXI)
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_HAS_STRNCPY_FROM_USER
>>       select ARCH_HAS_STRNLEN_USER
>>       select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
>> diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig
>> index e5936417d3cd3..7183eea282212 100644
>> --- a/arch/nios2/Kconfig
>> +++ b/arch/nios2/Kconfig
>> @@ -3,6 +3,7 @@ config NIOS2
>>       def_bool y
>>       select ARCH_32BIT_OFF_T
>>       select ARCH_HAS_DMA_PREP_COHERENT
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_HAS_SYNC_DMA_FOR_CPU
>>       select ARCH_HAS_SYNC_DMA_FOR_DEVICE
>>       select ARCH_HAS_DMA_SET_UNCACHED
>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
>> index bff5820b7cda1..b1acad3076180 100644
>> --- a/arch/powerpc/Kconfig
>> +++ b/arch/powerpc/Kconfig
>> @@ -148,6 +148,7 @@ config PPC
>>       select ARCH_HAS_PTE_DEVMAP        if PPC_BOOK3S_64
>>       select ARCH_HAS_PTE_SPECIAL
>>       select ARCH_HAS_SCALED_CPUTIME        if 
>> VIRT_CPU_ACCOUNTING_NATIVE && PPC_BOOK3S_64
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_HAS_SET_MEMORY
>>       select ARCH_HAS_STRICT_KERNEL_RWX    if (PPC_BOOK3S || PPC_8xx 
>> || 40x) && !HIBERNATION
>>       select ARCH_HAS_STRICT_KERNEL_RWX    if PPC_85xx && 
>> !HIBERNATION && !RANDOMIZE_BASE
>> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
>> index 5966ad97c30c3..b5a48f8424af9 100644
>> --- a/arch/riscv/Kconfig
>> +++ b/arch/riscv/Kconfig
>> @@ -29,6 +29,7 @@ config RISCV
>>       select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
>>       select ARCH_HAS_PMEM_API
>>       select ARCH_HAS_PTE_SPECIAL
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_HAS_SET_DIRECT_MAP if MMU
>>       select ARCH_HAS_SET_MEMORY if MMU
>>       select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
>> diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
>> index 04b9550cf0070..001f5149952b4 100644
>> --- a/arch/sh/Kconfig
>> +++ b/arch/sh/Kconfig
>> @@ -10,6 +10,7 @@ config SUPERH
>>       select ARCH_HAS_GIGANTIC_PAGE
>>       select ARCH_HAS_GCOV_PROFILE_ALL
>>       select ARCH_HAS_PTE_SPECIAL
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
>>       select ARCH_HIBERNATION_POSSIBLE if MMU
>>       select ARCH_MIGHT_HAVE_PC_PARPORT
>> diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
>> index 8535e19062f65..e4bfb80b48cfe 100644
>> --- a/arch/sparc/Kconfig
>> +++ b/arch/sparc/Kconfig
>> @@ -13,6 +13,7 @@ config 64BIT
>>   config SPARC
>>       bool
>>       default y
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_MIGHT_HAVE_PC_PARPORT if SPARC64 && PCI
>>       select ARCH_MIGHT_HAVE_PC_SERIO
>>       select DMA_OPS
>> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
>> index 53bab123a8ee4..d7c2bf4ee403d 100644
>> --- a/arch/x86/Kconfig
>> +++ b/arch/x86/Kconfig
>> @@ -91,6 +91,7 @@ config X86
>>       select ARCH_HAS_NONLEAF_PMD_YOUNG    if PGTABLE_LEVELS > 2
>>       select ARCH_HAS_UACCESS_FLUSHCACHE    if X86_64
>>       select ARCH_HAS_COPY_MC            if X86_64
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_HAS_SET_MEMORY
>>       select ARCH_HAS_SET_DIRECT_MAP
>>       select ARCH_HAS_STRICT_KERNEL_RWX
>> diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
>> index 3c6e5471f025b..c6cbd7459939c 100644
>> --- a/arch/xtensa/Kconfig
>> +++ b/arch/xtensa/Kconfig
>> @@ -8,6 +8,7 @@ config XTENSA
>>       select ARCH_HAS_DMA_PREP_COHERENT if MMU
>>       select ARCH_HAS_GCOV_PROFILE_ALL
>>       select ARCH_HAS_KCOV
>> +    select ARCH_HAS_SCREEN_INFO
>>       select ARCH_HAS_SYNC_DMA_FOR_CPU if MMU
>>       select ARCH_HAS_SYNC_DMA_FOR_DEVICE if MMU
>>       select ARCH_HAS_DMA_SET_UNCACHED if MMU
>> diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
>> index 8b2b9ac37c3df..d4a72bea56be0 100644
>> --- a/drivers/video/Kconfig
>> +++ b/drivers/video/Kconfig
>> @@ -21,6 +21,9 @@ config STI_CORE
>>   config VIDEO_CMDLINE
>>       bool
>>   +config ARCH_HAS_SCREEN_INFO
>> +    bool
>> +
>>   config VIDEO_NOMODESET
>>       bool
>>       default n
>> diff --git a/include/asm-generic/Kbuild b/include/asm-generic/Kbuild
>> index 941be574bbe00..5e5d4158a4b4b 100644
>> --- a/include/asm-generic/Kbuild
>> +++ b/include/asm-generic/Kbuild
>> @@ -47,6 +47,7 @@ mandatory-y += percpu.h
>>   mandatory-y += pgalloc.h
>>   mandatory-y += preempt.h
>>   mandatory-y += rwonce.h
>> +mandatory-y += screen_info.h
>>   mandatory-y += sections.h
>>   mandatory-y += serial.h
>>   mandatory-y += shmparam.h
>> diff --git a/include/asm-generic/screen_info.h 
>> b/include/asm-generic/screen_info.h
>> new file mode 100644
>> index 0000000000000..6fd0e50fabfcd
>> --- /dev/null
>> +++ b/include/asm-generic/screen_info.h
>> @@ -0,0 +1,12 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +
>> +#ifndef _ASM_GENERIC_SCREEN_INFO_H
>> +#define _ASM_GENERIC_SCREEN_INFO_H
>> +
>> +#include <uapi/linux/screen_info.h>
>> +
>> +#if defined(CONFIG_ARCH_HAS_SCREEN_INFO)
>> +extern struct screen_info screen_info;
>> +#endif
>> +
>> +#endif /* _ASM_GENERIC_SCREEN_INFO_H */
>> diff --git a/include/linux/screen_info.h b/include/linux/screen_info.h
>> index eab7081392d50..c764b9a51c24b 100644
>> --- a/include/linux/screen_info.h
>> +++ b/include/linux/screen_info.h
>> @@ -4,6 +4,6 @@
>>     #include <uapi/linux/screen_info.h>
>>   -extern struct screen_info screen_info;
>> +#include <asm/screen_info.h>
>>     #endif /* _SCREEN_INFO_H */
diff mbox series

Patch

diff --git a/arch/Kconfig b/arch/Kconfig
index 205fd23e0cada..2f58293fd7bcb 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -1466,6 +1466,12 @@  config ARCH_HAS_NONLEAF_PMD_YOUNG
 	  address translations. Page table walkers that clear the accessed bit
 	  may use this capability to reduce their search space.
 
+config ARCH_HAS_SCREEN_INFO
+	bool
+	help
+	  Selected by architectures that provide a global instance of
+	  screen_info.
+
 source "kernel/gcov/Kconfig"
 
 source "scripts/gcc-plugins/Kconfig"
diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index a5c2b1aa46b02..d749011d88b14 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -4,6 +4,7 @@  config ALPHA
 	default y
 	select ARCH_32BIT_USTAT_F_TINODE
 	select ARCH_HAS_CURRENT_STACK_POINTER
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_MIGHT_HAVE_PC_PARPORT
 	select ARCH_MIGHT_HAVE_PC_SERIO
 	select ARCH_NO_PREEMPT
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 0fb4b218f6658..a9d01ee67a90e 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -15,6 +15,7 @@  config ARM
 	select ARCH_HAS_MEMBARRIER_SYNC_CORE
 	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
 	select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_HAS_SETUP_DMA_OPS
 	select ARCH_HAS_SET_MEMORY
 	select ARCH_STACKWALK
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 343e1e1cae10a..21addc4715bb3 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -36,6 +36,7 @@  config ARM64
 	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
 	select ARCH_HAS_PTE_DEVMAP
 	select ARCH_HAS_PTE_SPECIAL
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_HAS_SETUP_DMA_OPS
 	select ARCH_HAS_SET_DIRECT_MAP
 	select ARCH_HAS_SET_MEMORY
diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
index 4df1f8c9d170b..28444e581fc1f 100644
--- a/arch/csky/Kconfig
+++ b/arch/csky/Kconfig
@@ -10,6 +10,7 @@  config CSKY
 	select ARCH_USE_QUEUED_RWLOCKS
 	select ARCH_USE_QUEUED_SPINLOCKS
 	select ARCH_HAS_CURRENT_STACK_POINTER
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_INLINE_READ_LOCK if !PREEMPTION
 	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
 	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig
index 54eadf2651786..cc683c0a43d34 100644
--- a/arch/hexagon/Kconfig
+++ b/arch/hexagon/Kconfig
@@ -5,6 +5,7 @@  comment "Linux Kernel Configuration for Hexagon"
 config HEXAGON
 	def_bool y
 	select ARCH_32BIT_OFF_T
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
 	select ARCH_NO_PREEMPT
 	select DMA_GLOBAL_POOL
diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index e79f15e32a451..8b1e785e6d53d 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -10,6 +10,7 @@  config IA64
 	bool
 	select ARCH_BINFMT_ELF_EXTRA_PHDRS
 	select ARCH_HAS_DMA_MARK_CLEAN
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_HAS_STRNCPY_FROM_USER
 	select ARCH_HAS_STRNLEN_USER
 	select ARCH_MIGHT_HAVE_PC_PARPORT
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index d38b066fc931b..6aab2fb7753da 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -13,6 +13,7 @@  config LOONGARCH
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
 	select ARCH_HAS_PTE_SPECIAL
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
 	select ARCH_INLINE_READ_LOCK if !PREEMPTION
 	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 675a8660cb85a..c0ae09789cb6d 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -10,6 +10,7 @@  config MIPS
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE if !EVA
 	select ARCH_HAS_PTE_SPECIAL if !(32BIT && CPU_HAS_RIXI)
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_HAS_STRNCPY_FROM_USER
 	select ARCH_HAS_STRNLEN_USER
 	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig
index e5936417d3cd3..7183eea282212 100644
--- a/arch/nios2/Kconfig
+++ b/arch/nios2/Kconfig
@@ -3,6 +3,7 @@  config NIOS2
 	def_bool y
 	select ARCH_32BIT_OFF_T
 	select ARCH_HAS_DMA_PREP_COHERENT
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_HAS_SYNC_DMA_FOR_CPU
 	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
 	select ARCH_HAS_DMA_SET_UNCACHED
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index bff5820b7cda1..b1acad3076180 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -148,6 +148,7 @@  config PPC
 	select ARCH_HAS_PTE_DEVMAP		if PPC_BOOK3S_64
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_SCALED_CPUTIME		if VIRT_CPU_ACCOUNTING_NATIVE && PPC_BOOK3S_64
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_HAS_SET_MEMORY
 	select ARCH_HAS_STRICT_KERNEL_RWX	if (PPC_BOOK3S || PPC_8xx || 40x) && !HIBERNATION
 	select ARCH_HAS_STRICT_KERNEL_RWX	if PPC_85xx && !HIBERNATION && !RANDOMIZE_BASE
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 5966ad97c30c3..b5a48f8424af9 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -29,6 +29,7 @@  config RISCV
 	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
 	select ARCH_HAS_PMEM_API
 	select ARCH_HAS_PTE_SPECIAL
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_HAS_SET_DIRECT_MAP if MMU
 	select ARCH_HAS_SET_MEMORY if MMU
 	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 04b9550cf0070..001f5149952b4 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -10,6 +10,7 @@  config SUPERH
 	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_HAS_GCOV_PROFILE_ALL
 	select ARCH_HAS_PTE_SPECIAL
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
 	select ARCH_HIBERNATION_POSSIBLE if MMU
 	select ARCH_MIGHT_HAVE_PC_PARPORT
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 8535e19062f65..e4bfb80b48cfe 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -13,6 +13,7 @@  config 64BIT
 config SPARC
 	bool
 	default y
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_MIGHT_HAVE_PC_PARPORT if SPARC64 && PCI
 	select ARCH_MIGHT_HAVE_PC_SERIO
 	select DMA_OPS
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 53bab123a8ee4..d7c2bf4ee403d 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -91,6 +91,7 @@  config X86
 	select ARCH_HAS_NONLEAF_PMD_YOUNG	if PGTABLE_LEVELS > 2
 	select ARCH_HAS_UACCESS_FLUSHCACHE	if X86_64
 	select ARCH_HAS_COPY_MC			if X86_64
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_HAS_SET_MEMORY
 	select ARCH_HAS_SET_DIRECT_MAP
 	select ARCH_HAS_STRICT_KERNEL_RWX
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 3c6e5471f025b..c6cbd7459939c 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -8,6 +8,7 @@  config XTENSA
 	select ARCH_HAS_DMA_PREP_COHERENT if MMU
 	select ARCH_HAS_GCOV_PROFILE_ALL
 	select ARCH_HAS_KCOV
+	select ARCH_HAS_SCREEN_INFO
 	select ARCH_HAS_SYNC_DMA_FOR_CPU if MMU
 	select ARCH_HAS_SYNC_DMA_FOR_DEVICE if MMU
 	select ARCH_HAS_DMA_SET_UNCACHED if MMU
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 8b2b9ac37c3df..d4a72bea56be0 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -21,6 +21,9 @@  config STI_CORE
 config VIDEO_CMDLINE
 	bool
 
+config ARCH_HAS_SCREEN_INFO
+	bool
+
 config VIDEO_NOMODESET
 	bool
 	default n
diff --git a/include/asm-generic/Kbuild b/include/asm-generic/Kbuild
index 941be574bbe00..5e5d4158a4b4b 100644
--- a/include/asm-generic/Kbuild
+++ b/include/asm-generic/Kbuild
@@ -47,6 +47,7 @@  mandatory-y += percpu.h
 mandatory-y += pgalloc.h
 mandatory-y += preempt.h
 mandatory-y += rwonce.h
+mandatory-y += screen_info.h
 mandatory-y += sections.h
 mandatory-y += serial.h
 mandatory-y += shmparam.h
diff --git a/include/asm-generic/screen_info.h b/include/asm-generic/screen_info.h
new file mode 100644
index 0000000000000..6fd0e50fabfcd
--- /dev/null
+++ b/include/asm-generic/screen_info.h
@@ -0,0 +1,12 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _ASM_GENERIC_SCREEN_INFO_H
+#define _ASM_GENERIC_SCREEN_INFO_H
+
+#include <uapi/linux/screen_info.h>
+
+#if defined(CONFIG_ARCH_HAS_SCREEN_INFO)
+extern struct screen_info screen_info;
+#endif
+
+#endif /* _ASM_GENERIC_SCREEN_INFO_H */
diff --git a/include/linux/screen_info.h b/include/linux/screen_info.h
index eab7081392d50..c764b9a51c24b 100644
--- a/include/linux/screen_info.h
+++ b/include/linux/screen_info.h
@@ -4,6 +4,6 @@ 
 
 #include <uapi/linux/screen_info.h>
 
-extern struct screen_info screen_info;
+#include <asm/screen_info.h>
 
 #endif /* _SCREEN_INFO_H */