Re: [06/12] arch: Declare screen_info in <asm/screen_info.h>
From: suijingfeng <hidden>
Date: 2023-08-18 14:07:05
Also in:
dri-devel, linux-alpha, linux-arch, linux-efi, linux-fbdev, linux-hyperv, linux-mips, linux-riscv, linux-sh, linux-staging, lkml, loongarch, sparclinux
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:
quoted hunk ↗ jump to hunk
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 <redacted> 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 <redacted> 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 <redacted> Cc: Paul Walmsley <redacted> 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 <redacted> 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 <redacted> 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 <redacted> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Anshuman Khandual <redacted> Cc: Niklas Schnelle <schnelle@linux.ibm.com> Cc: "Russell King (Oracle)" <redacted> Cc: Linus Walleij <redacted> Cc: Sebastian Reichel <redacted> Cc: "Mike Rapoport (IBM)" <rppt@kernel.org> Cc: "Kirill A. Shutemov" <redacted> Cc: Zi Yan <ziy@nvidia.com> Acked-by: WANG Xuerui <redacted> # 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.hdiff --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_PREEMPTdiff --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_STACKWALKdiff --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_MEMORYdiff --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 !PREEMPTIONdiff --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_POOLdiff --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_PARPORTdiff --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 !PREEMPTIONdiff --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_BROADCASTdiff --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_UNCACHEDdiff --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_BASEdiff --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_KERNELdiff --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_PARPORTdiff --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_OPSdiff --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_RWXdiff --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 MMUdiff --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 ndiff --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.hdiff --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 */