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Mon, 27 Dec 2021 16:43:27 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8C058A4062; Mon, 27 Dec 2021 16:43:27 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0FBADA405B; Mon, 27 Dec 2021 16:43:26 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 27 Dec 2021 16:43:25 +0000 (GMT) From: Niklas Schnelle To: Arnd Bergmann , Bjorn Helgaas , John Garry , Nick Hu , Greentime Hu , Vincent Chen , Paul Walmsley , Palmer Dabbelt , Albert Ou , Guo Ren , Dinh Nguyen , Chris Zankel , Karol Gugala , Jeff Dike , Yoshinori Sato , Brian Cain , Heiko Carstens , Richard Henderson , Ivan Kokshaysky , Matt Turner , Vineet Gupta , Russell King , Catalin Marinas , Will Deacon , Geert Uytterhoeven , Michal Simek , Thomas Bogendoerfer , "James E.J. Bottomley" , Helge Deller , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Rich Felker , "David S. Miller" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-pci@vger.kernel.org, linux-riscv@lists.infradead.org, linux-csky@vger.kernel.org, linux-xtensa@linux-xtensa.org, openrisc@lists.librecores.org, linux-s390@vger.kernel.org, linux-alpha@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org Subject: [RFC 02/32] Kconfig: introduce HAS_IOPORT option and select it as necessary Date: Mon, 27 Dec 2021 17:42:47 +0100 Message-Id: <20211227164317.4146918-3-schnelle@linux.ibm.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20211227164317.4146918-1-schnelle@linux.ibm.com> References: <20211227164317.4146918-1-schnelle@linux.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-GUID: isunVRZjJ6JiKqeiQVOJvEmV8qSRZgu6 X-Proofpoint-ORIG-GUID: NOj8zVp-UdJWaGmLhuKmlC5md2AkCEZR X-Proofpoint-UnRewURL: 0 URL was un-rewritten MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.790,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2021-12-27_08,2021-12-24_01,2021-12-02_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 phishscore=0 spamscore=0 mlxscore=0 impostorscore=0 mlxlogscore=872 priorityscore=1501 bulkscore=0 clxscore=1011 malwarescore=0 suspectscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2110150000 definitions=main-2112270080 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211227_084411_691757_8E81E645 X-CRM114-Status: GOOD ( 24.71 ) X-Spam-Score: -0.1 (/) X-Spam-Report: Spam detection software, running on the system "bombadil.infradead.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: We introduce a new HAS_IOPORT Kconfig option to gate support for I/O port access. In a future patch HAS_IOPORT=n will disable compilation of the I/O accessor functions inb()/outb() and friends on arch [...] Content analysis details: (-0.1 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_MSPIKE_H2 RBL: Average reputation (+2) [148.163.158.5 listed in wl.mailspike.net] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain X-BeenThere: linux-snps-arc@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux on Synopsys ARC Processors List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-snps-arc" Errors-To: linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org We introduce a new HAS_IOPORT Kconfig option to gate support for I/O port access. In a future patch HAS_IOPORT=n will disable compilation of the I/O accessor functions inb()/outb() and friends on architectures which can not meaningfully support legacy I/O spaces. On these platforms inb()/outb() etc are currently just stubs in asm-generic/io.h which when called will cause a NULL pointer access which some compilers actually detect and warn about. The dependencies on HAS_IOPORT in drivers as well as ifdefs for HAS_IOPORT specific sections will be added in subsequent patches on a per subsystem basis. Then a final patch will ifdef the I/O access functions on HAS_IOPORT thus turning any use not gated by HAS_IOPORT into a compile-time warning. Link: https://lore.kernel.org/lkml/CAHk-=wg80je=K7madF4e7WrRNp37e3qh6y10Svhdc7O8SZ_-8g@mail.gmail.com/ Co-developed-by: Arnd Bergmann Signed-off-by: Arnd Bergmann Signed-off-by: Niklas Schnelle --- arch/alpha/Kconfig | 1 + arch/arc/Kconfig | 1 + arch/arm/Kconfig | 1 + arch/arm64/Kconfig | 1 + arch/ia64/Kconfig | 1 + arch/m68k/Kconfig | 1 + arch/microblaze/Kconfig | 1 + arch/mips/Kconfig | 1 + arch/parisc/Kconfig | 1 + arch/powerpc/Kconfig | 1 + arch/riscv/Kconfig | 1 + arch/sh/Kconfig | 1 + arch/sparc/Kconfig | 1 + arch/x86/Kconfig | 1 + drivers/bus/Kconfig | 2 +- lib/Kconfig | 4 ++++ lib/Kconfig.kgdb | 1 + 17 files changed, 20 insertions(+), 1 deletion(-) diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig index 4e87783c90ad..472a0c5e4c2f 100644 --- a/arch/alpha/Kconfig +++ b/arch/alpha/Kconfig @@ -28,6 +28,7 @@ config ALPHA select AUDIT_ARCH select GENERIC_CPU_VULNERABILITIES select GENERIC_SMP_IDLE_THREAD + select HAS_IOPORT select HAVE_ARCH_AUDITSYSCALL select HAVE_MOD_ARCH_SPECIFIC select MODULES_USE_ELF_RELA diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index b4ae6058902a..b3911ebbd237 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -27,6 +27,7 @@ config ARC select GENERIC_PENDING_IRQ if SMP select GENERIC_SCHED_CLOCK select GENERIC_SMP_IDLE_THREAD + select HAS_IOPORT select HAVE_ARCH_KGDB select HAVE_ARCH_TRACEHOOK select HAVE_ARCH_TRANSPARENT_HUGEPAGE if ARC_MMU_V4 diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index c2724d986fa0..605709b6eecb 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -66,6 +66,7 @@ config ARM select GENERIC_SCHED_CLOCK select GENERIC_SMP_IDLE_THREAD select HARDIRQS_SW_RESEND + select HAS_IOPORT select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index c4207cf9bb17..a8b199a40c8f 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -135,6 +135,7 @@ config ARM64 select GENERIC_GETTIMEOFDAY select GENERIC_VDSO_TIME_NS select HARDIRQS_SW_RESEND + select HAS_IOPORT select HAVE_MOVE_PMD select HAVE_MOVE_PUD select HAVE_PCI diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index 1e33666fa679..672aa2a88b19 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -24,6 +24,7 @@ config IA64 select PCI_DOMAINS if PCI select PCI_MSI select PCI_SYSCALL if PCI + select HAS_IOPORT select HAVE_ASM_MODVERSIONS select HAVE_UNSTABLE_SCHED_CLOCK select HAVE_EXIT_THREAD diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index 0b50da08a9c5..926d97c33828 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -16,6 +16,7 @@ config M68K select GENERIC_CPU_DEVICES select GENERIC_IOMAP select GENERIC_IRQ_SHOW + select HAS_IOPORT select HAVE_AOUT if MMU select HAVE_ASM_MODVERSIONS select HAVE_DEBUG_BUGVERBOSE diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig index 59798e43cdb0..213ef2940079 100644 --- a/arch/microblaze/Kconfig +++ b/arch/microblaze/Kconfig @@ -21,6 +21,7 @@ config MICROBLAZE select GENERIC_IRQ_SHOW select GENERIC_PCI_IOMAP select GENERIC_SCHED_CLOCK + select HAS_IOPORT if PCI select HAVE_ARCH_HASH select HAVE_ARCH_KGDB select HAVE_ARCH_SECCOMP diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 0215dc1529e9..87e6e7c29493 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -47,6 +47,7 @@ config MIPS select GENERIC_SMP_IDLE_THREAD select GENERIC_TIME_VSYSCALL select GUP_GET_PTE_LOW_HIGH if CPU_MIPS32 && PHYS_ADDR_T_64BIT + select HAS_IOPORT select HAVE_ARCH_COMPILER_H select HAVE_ARCH_JUMP_LABEL select HAVE_ARCH_KGDB if MIPS_FP_SUPPORT diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index 011dc32fdb4d..b352c6dbbead 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -43,6 +43,7 @@ config PARISC select MODULES_USE_ELF_RELA select CLONE_BACKWARDS select TTY # Needed for pdc_cons.c + select HAS_IOPORT if PCI || EISA select HAVE_DEBUG_STACKOVERFLOW select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_HASH diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index dea74d7717c0..d39ba34d839a 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -185,6 +185,7 @@ config PPC select GENERIC_SMP_IDLE_THREAD select GENERIC_TIME_VSYSCALL select GENERIC_VDSO_TIME_NS + select HAS_IOPORT if PCI select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP select HAVE_ARCH_HUGE_VMAP if PPC_RADIX_MMU || PPC_8xx diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 821252b65f89..b69cc86522fb 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -63,6 +63,7 @@ config RISCV select GENERIC_SMP_IDLE_THREAD select GENERIC_TIME_VSYSCALL if MMU && 64BIT select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO + select HAS_IOPORT if MMU select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig index 70afb30e0b32..334a52535379 100644 --- a/arch/sh/Kconfig +++ b/arch/sh/Kconfig @@ -24,6 +24,7 @@ config SUPERH select GENERIC_SCHED_CLOCK select GENERIC_SMP_IDLE_THREAD select GUP_GET_PTE_LOW_HIGH if X2TLB + select HAS_IOPORT if HAS_IOPORT_MAP select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_KGDB select HAVE_ARCH_SECCOMP_FILTER diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index 66fc08646be5..728598673724 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -32,6 +32,7 @@ config SPARC select GENERIC_IRQ_SHOW select ARCH_WANT_IPC_PARSE_VERSION select GENERIC_PCI_IOMAP + select HAS_IOPORT select HAVE_NMI_WATCHDOG if SPARC64 select HAVE_CBPF_JIT if SPARC32 select HAVE_EBPF_JIT if SPARC64 diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 5c2ccb85f2ef..8d3cfd693559 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -153,6 +153,7 @@ config X86 select GUP_GET_PTE_LOW_HIGH if X86_PAE select HARDIRQS_SW_RESEND select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 + select HAS_IOPORT select HAVE_ACPI_APEI if ACPI select HAVE_ACPI_APEI_NMI if ACPI select HAVE_ALIGNED_STRUCT_PAGE if SLUB diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig index 3c68e174a113..a61285100224 100644 --- a/drivers/bus/Kconfig +++ b/drivers/bus/Kconfig @@ -81,7 +81,7 @@ config MOXTET config HISILICON_LPC bool "Support for ISA I/O space on HiSilicon Hip06/7" depends on (ARM64 && ARCH_HISI) || (COMPILE_TEST && !ALPHA && !HEXAGON && !PARISC) - depends on HAS_IOMEM + depends on HAS_IOPORT select INDIRECT_PIO if ARM64 help Driver to enable I/O access to devices attached to the Low Pin diff --git a/lib/Kconfig b/lib/Kconfig index 5e7165e6a346..e55746625762 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -95,6 +95,7 @@ config ARCH_USE_SYM_ANNOTATIONS config INDIRECT_PIO bool "Access I/O in non-MMIO mode" depends on ARM64 + depends on HAS_IOPORT help On some platforms where no separate I/O space exists, there are I/O hosts which can not be accessed in MMIO mode. Using the logical PIO @@ -486,6 +487,9 @@ config HAS_IOMEM depends on !NO_IOMEM default y +config HAS_IOPORT + def_bool ISA || LEGACY_PCI + config HAS_IOPORT_MAP bool depends on HAS_IOMEM && !NO_IOPORT_MAP diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb index 05dae05b6cc9..c68e4d9dcecb 100644 --- a/lib/Kconfig.kgdb +++ b/lib/Kconfig.kgdb @@ -121,6 +121,7 @@ config KDB_DEFAULT_ENABLE config KDB_KEYBOARD bool "KGDB_KDB: keyboard as input device" + depends on HAS_IOPORT depends on VT && KGDB_KDB default n help