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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 655 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-27 08:55:21 +02:00
/* SPDX-License-Identifier: GPL-2.0-only */
arm64: Kprobes with single stepping support Add support for basic kernel probes(kprobes) and jump probes (jprobes) for ARM64. Kprobes utilizes software breakpoint and single step debug exceptions supported on ARM v8. A software breakpoint is placed at the probe address to trap the kernel execution into the kprobe handler. ARM v8 supports enabling single stepping before the break exception return (ERET), with next PC in exception return address (ELR_EL1). The kprobe handler prepares an executable memory slot for out-of-line execution with a copy of the original instruction being probed, and enables single stepping. The PC is set to the out-of-line slot address before the ERET. With this scheme, the instruction is executed with the exact same register context except for the PC (and DAIF) registers. Debug mask (PSTATE.D) is enabled only when single stepping a recursive kprobe, e.g.: during kprobes reenter so that probed instruction can be single stepped within the kprobe handler -exception- context. The recursion depth of kprobe is always 2, i.e. upon probe re-entry, any further re-entry is prevented by not calling handlers and the case counted as a missed kprobe). Single stepping from the x-o-l slot has a drawback for PC-relative accesses like branching and symbolic literals access as the offset from the new PC (slot address) may not be ensured to fit in the immediate value of the opcode. Such instructions need simulation, so reject probing them. Instructions generating exceptions or cpu mode change are rejected for probing. Exclusive load/store instructions are rejected too. Additionally, the code is checked to see if it is inside an exclusive load/store sequence (code from Pratyush). System instructions are mostly enabled for stepping, except MSR/MRS accesses to "DAIF" flags in PSTATE, which are not safe for probing. This also changes arch/arm64/include/asm/ptrace.h to use include/asm-generic/ptrace.h. Thanks to Steve Capper and Pratyush Anand for several suggested Changes. Signed-off-by: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com> Signed-off-by: David A. Long <dave.long@linaro.org> Signed-off-by: Pratyush Anand <panand@redhat.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-08 12:35:48 -04:00
/*
* arch/arm64/include/asm/probes.h
*
* Copyright (C) 2013 Linaro Limited
*/
#ifndef _ARM_PROBES_H
#define _ARM_PROBES_H
arm64/fpsimd: add <asm/insn.h> to <asm/kprobes.h> to fix fpsimd build Adding <asm/exception.h> brought in <asm/kprobes.h> which uses <asm/probes.h>, which uses 'pstate_check_t' so the latter needs to #include <asm/insn.h> for this typedef. Fixes this build error: In file included from arch/arm64/include/asm/kprobes.h:24, from arch/arm64/include/asm/exception.h:11, from arch/arm64/kernel/fpsimd.c:35: arch/arm64/include/asm/probes.h:16:2: error: unknown type name 'pstate_check_t' 16 | pstate_check_t *pstate_cc; Fixes: c6b90d5cf637 ("arm64/fpsimd: Fix missing-prototypes in fpsimd.c") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Will Deacon <will@kernel.org> Cc: Tian Tao <tiantao6@hisilicon.com> Link: https://lore.kernel.org/r/20201123044510.9942-1-rdunlap@infradead.org Signed-off-by: Will Deacon <will@kernel.org>
2020-11-22 20:45:10 -08:00
#include <asm/insn.h>
arm64: kprobe: protect/rename few definitions to be reused by uprobe decode-insn code has to be reused by arm64 uprobe implementation as well. Therefore, this patch protects some portion of kprobe code and renames few other, so that decode-insn functionality can be reused by uprobe even when CONFIG_KPROBES is not defined. kprobe_opcode_t and struct arch_specific_insn are also defined by linux/kprobes.h, when CONFIG_KPROBES is not defined. So, protect these definitions in asm/probes.h. linux/kprobes.h already includes asm/kprobes.h. Therefore, remove inclusion of asm/kprobes.h from decode-insn.c. There are some definitions like kprobe_insn and kprobes_handler_t etc can be re-used by uprobe. So, it would be better to remove 'k' from their names. struct arch_specific_insn is specific to kprobe. Therefore, introduce a new struct arch_probe_insn which will be common for both kprobe and uprobe, so that decode-insn code can be shared. Modify kprobe code accordingly. Function arm_probe_decode_insn() will be needed by uprobe as well. So make it global. Signed-off-by: Pratyush Anand <panand@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-02 14:40:41 +05:30
typedef void (probes_handler_t) (u32 opcode, long addr, struct pt_regs *);
arm64: Kprobes with single stepping support Add support for basic kernel probes(kprobes) and jump probes (jprobes) for ARM64. Kprobes utilizes software breakpoint and single step debug exceptions supported on ARM v8. A software breakpoint is placed at the probe address to trap the kernel execution into the kprobe handler. ARM v8 supports enabling single stepping before the break exception return (ERET), with next PC in exception return address (ELR_EL1). The kprobe handler prepares an executable memory slot for out-of-line execution with a copy of the original instruction being probed, and enables single stepping. The PC is set to the out-of-line slot address before the ERET. With this scheme, the instruction is executed with the exact same register context except for the PC (and DAIF) registers. Debug mask (PSTATE.D) is enabled only when single stepping a recursive kprobe, e.g.: during kprobes reenter so that probed instruction can be single stepped within the kprobe handler -exception- context. The recursion depth of kprobe is always 2, i.e. upon probe re-entry, any further re-entry is prevented by not calling handlers and the case counted as a missed kprobe). Single stepping from the x-o-l slot has a drawback for PC-relative accesses like branching and symbolic literals access as the offset from the new PC (slot address) may not be ensured to fit in the immediate value of the opcode. Such instructions need simulation, so reject probing them. Instructions generating exceptions or cpu mode change are rejected for probing. Exclusive load/store instructions are rejected too. Additionally, the code is checked to see if it is inside an exclusive load/store sequence (code from Pratyush). System instructions are mostly enabled for stepping, except MSR/MRS accesses to "DAIF" flags in PSTATE, which are not safe for probing. This also changes arch/arm64/include/asm/ptrace.h to use include/asm-generic/ptrace.h. Thanks to Steve Capper and Pratyush Anand for several suggested Changes. Signed-off-by: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com> Signed-off-by: David A. Long <dave.long@linaro.org> Signed-off-by: Pratyush Anand <panand@redhat.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-08 12:35:48 -04:00
arm64: kprobe: protect/rename few definitions to be reused by uprobe decode-insn code has to be reused by arm64 uprobe implementation as well. Therefore, this patch protects some portion of kprobe code and renames few other, so that decode-insn functionality can be reused by uprobe even when CONFIG_KPROBES is not defined. kprobe_opcode_t and struct arch_specific_insn are also defined by linux/kprobes.h, when CONFIG_KPROBES is not defined. So, protect these definitions in asm/probes.h. linux/kprobes.h already includes asm/kprobes.h. Therefore, remove inclusion of asm/kprobes.h from decode-insn.c. There are some definitions like kprobe_insn and kprobes_handler_t etc can be re-used by uprobe. So, it would be better to remove 'k' from their names. struct arch_specific_insn is specific to kprobe. Therefore, introduce a new struct arch_probe_insn which will be common for both kprobe and uprobe, so that decode-insn code can be shared. Modify kprobe code accordingly. Function arm_probe_decode_insn() will be needed by uprobe as well. So make it global. Signed-off-by: Pratyush Anand <panand@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-02 14:40:41 +05:30
struct arch_probe_insn {
probes_handler_t *handler;
arm64: Kprobes with single stepping support Add support for basic kernel probes(kprobes) and jump probes (jprobes) for ARM64. Kprobes utilizes software breakpoint and single step debug exceptions supported on ARM v8. A software breakpoint is placed at the probe address to trap the kernel execution into the kprobe handler. ARM v8 supports enabling single stepping before the break exception return (ERET), with next PC in exception return address (ELR_EL1). The kprobe handler prepares an executable memory slot for out-of-line execution with a copy of the original instruction being probed, and enables single stepping. The PC is set to the out-of-line slot address before the ERET. With this scheme, the instruction is executed with the exact same register context except for the PC (and DAIF) registers. Debug mask (PSTATE.D) is enabled only when single stepping a recursive kprobe, e.g.: during kprobes reenter so that probed instruction can be single stepped within the kprobe handler -exception- context. The recursion depth of kprobe is always 2, i.e. upon probe re-entry, any further re-entry is prevented by not calling handlers and the case counted as a missed kprobe). Single stepping from the x-o-l slot has a drawback for PC-relative accesses like branching and symbolic literals access as the offset from the new PC (slot address) may not be ensured to fit in the immediate value of the opcode. Such instructions need simulation, so reject probing them. Instructions generating exceptions or cpu mode change are rejected for probing. Exclusive load/store instructions are rejected too. Additionally, the code is checked to see if it is inside an exclusive load/store sequence (code from Pratyush). System instructions are mostly enabled for stepping, except MSR/MRS accesses to "DAIF" flags in PSTATE, which are not safe for probing. This also changes arch/arm64/include/asm/ptrace.h to use include/asm-generic/ptrace.h. Thanks to Steve Capper and Pratyush Anand for several suggested Changes. Signed-off-by: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com> Signed-off-by: David A. Long <dave.long@linaro.org> Signed-off-by: Pratyush Anand <panand@redhat.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-08 12:35:48 -04:00
};
arm64: kprobe: protect/rename few definitions to be reused by uprobe decode-insn code has to be reused by arm64 uprobe implementation as well. Therefore, this patch protects some portion of kprobe code and renames few other, so that decode-insn functionality can be reused by uprobe even when CONFIG_KPROBES is not defined. kprobe_opcode_t and struct arch_specific_insn are also defined by linux/kprobes.h, when CONFIG_KPROBES is not defined. So, protect these definitions in asm/probes.h. linux/kprobes.h already includes asm/kprobes.h. Therefore, remove inclusion of asm/kprobes.h from decode-insn.c. There are some definitions like kprobe_insn and kprobes_handler_t etc can be re-used by uprobe. So, it would be better to remove 'k' from their names. struct arch_specific_insn is specific to kprobe. Therefore, introduce a new struct arch_probe_insn which will be common for both kprobe and uprobe, so that decode-insn code can be shared. Modify kprobe code accordingly. Function arm_probe_decode_insn() will be needed by uprobe as well. So make it global. Signed-off-by: Pratyush Anand <panand@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-02 14:40:41 +05:30
#ifdef CONFIG_KPROBES
arm64: probes: Cleanup kprobes endianness conversions The core kprobes code uses kprobe_opcode_t for the in-memory representation of an instruction, using 'kprobe_opcode_t *' for XOL slots. As arm64 instructions are always little-endian 32-bit values, kprobes_opcode_t should be __le32, but at the moment kprobe_opcode_t is typedef'd to u32. Today there is no functional issue as we convert values via cpu_to_le32() and le32_to_cpu() where necessary, but these conversions are inconsistent with the types used, causing sparse warnings: | CHECK arch/arm64/kernel/probes/kprobes.c | arch/arm64/kernel/probes/kprobes.c:102:21: warning: cast to restricted __le32 | CHECK arch/arm64/kernel/probes/decode-insn.c | arch/arm64/kernel/probes/decode-insn.c:122:46: warning: cast to restricted __le32 | arch/arm64/kernel/probes/decode-insn.c:124:50: warning: cast to restricted __le32 | arch/arm64/kernel/probes/decode-insn.c:136:31: warning: cast to restricted __le32 Improve this by making kprobes_opcode_t a typedef for __le32 and consistently using this for pointers to executable instructions. With this change we can rely on the type system to tell us where conversions are necessary. Since kprobe::opcode is changed from u32 to __le32, the existing le32_to_cpu() converion moves from the point this is initialized (in arch_prepare_kprobe()) to the points this is consumed when passed to a handler or text patching function. As kprobe::opcode isn't altered or consumed elsewhere, this shouldn't result in a functional change. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20241008155851.801546-6-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-08 16:58:50 +01:00
typedef __le32 kprobe_opcode_t;
arm64: kprobe: protect/rename few definitions to be reused by uprobe decode-insn code has to be reused by arm64 uprobe implementation as well. Therefore, this patch protects some portion of kprobe code and renames few other, so that decode-insn functionality can be reused by uprobe even when CONFIG_KPROBES is not defined. kprobe_opcode_t and struct arch_specific_insn are also defined by linux/kprobes.h, when CONFIG_KPROBES is not defined. So, protect these definitions in asm/probes.h. linux/kprobes.h already includes asm/kprobes.h. Therefore, remove inclusion of asm/kprobes.h from decode-insn.c. There are some definitions like kprobe_insn and kprobes_handler_t etc can be re-used by uprobe. So, it would be better to remove 'k' from their names. struct arch_specific_insn is specific to kprobe. Therefore, introduce a new struct arch_probe_insn which will be common for both kprobe and uprobe, so that decode-insn code can be shared. Modify kprobe code accordingly. Function arm_probe_decode_insn() will be needed by uprobe as well. So make it global. Signed-off-by: Pratyush Anand <panand@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-02 14:40:41 +05:30
struct arch_specific_insn {
struct arch_probe_insn api;
arm64: probes: Cleanup kprobes endianness conversions The core kprobes code uses kprobe_opcode_t for the in-memory representation of an instruction, using 'kprobe_opcode_t *' for XOL slots. As arm64 instructions are always little-endian 32-bit values, kprobes_opcode_t should be __le32, but at the moment kprobe_opcode_t is typedef'd to u32. Today there is no functional issue as we convert values via cpu_to_le32() and le32_to_cpu() where necessary, but these conversions are inconsistent with the types used, causing sparse warnings: | CHECK arch/arm64/kernel/probes/kprobes.c | arch/arm64/kernel/probes/kprobes.c:102:21: warning: cast to restricted __le32 | CHECK arch/arm64/kernel/probes/decode-insn.c | arch/arm64/kernel/probes/decode-insn.c:122:46: warning: cast to restricted __le32 | arch/arm64/kernel/probes/decode-insn.c:124:50: warning: cast to restricted __le32 | arch/arm64/kernel/probes/decode-insn.c:136:31: warning: cast to restricted __le32 Improve this by making kprobes_opcode_t a typedef for __le32 and consistently using this for pointers to executable instructions. With this change we can rely on the type system to tell us where conversions are necessary. Since kprobe::opcode is changed from u32 to __le32, the existing le32_to_cpu() converion moves from the point this is initialized (in arch_prepare_kprobe()) to the points this is consumed when passed to a handler or text patching function. As kprobe::opcode isn't altered or consumed elsewhere, this shouldn't result in a functional change. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20241008155851.801546-6-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-08 16:58:50 +01:00
kprobe_opcode_t *xol_insn;
arm64: probes: Move kprobes-specific fields We share struct arch_probe_insn between krpboes and uprobes, but most of its fields aren't necessary for uprobes: * The 'insn' field is only used by kprobes as a pointer to the XOL slot. * The 'restore' field is only used by probes as the PC to restore after stepping an instruction in the XOL slot. * The 'pstate_cc' field isn't used by kprobes or uprobes, and seems to only exist as a result of copy-pasting the 32-bit arm implementation of kprobes. As these fields live in struct arch_probe_insn they cannot use definitions that only exist when CONFIG_KPROBES=y, such as the kprobe_opcode_t typedef, which we'd like to use in subsequent patches. Clean this up by removing the 'pstate_cc' field, and moving the kprobes-specific fields into the kprobes-specific struct arch_specific_insn. To make it clear that the fields are related to stepping instructions in the XOL slot, 'insn' is renamed to 'xol_insn' and 'restore' is renamed to 'xol_restore' At the same time, remove the misleading and useless comment above struct arch_probe_insn. The should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20241008155851.801546-5-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-08 16:58:49 +01:00
/* restore address after step xol */
unsigned long xol_restore;
arm64: kprobe: protect/rename few definitions to be reused by uprobe decode-insn code has to be reused by arm64 uprobe implementation as well. Therefore, this patch protects some portion of kprobe code and renames few other, so that decode-insn functionality can be reused by uprobe even when CONFIG_KPROBES is not defined. kprobe_opcode_t and struct arch_specific_insn are also defined by linux/kprobes.h, when CONFIG_KPROBES is not defined. So, protect these definitions in asm/probes.h. linux/kprobes.h already includes asm/kprobes.h. Therefore, remove inclusion of asm/kprobes.h from decode-insn.c. There are some definitions like kprobe_insn and kprobes_handler_t etc can be re-used by uprobe. So, it would be better to remove 'k' from their names. struct arch_specific_insn is specific to kprobe. Therefore, introduce a new struct arch_probe_insn which will be common for both kprobe and uprobe, so that decode-insn code can be shared. Modify kprobe code accordingly. Function arm_probe_decode_insn() will be needed by uprobe as well. So make it global. Signed-off-by: Pratyush Anand <panand@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-02 14:40:41 +05:30
};
#endif
arm64: Kprobes with single stepping support Add support for basic kernel probes(kprobes) and jump probes (jprobes) for ARM64. Kprobes utilizes software breakpoint and single step debug exceptions supported on ARM v8. A software breakpoint is placed at the probe address to trap the kernel execution into the kprobe handler. ARM v8 supports enabling single stepping before the break exception return (ERET), with next PC in exception return address (ELR_EL1). The kprobe handler prepares an executable memory slot for out-of-line execution with a copy of the original instruction being probed, and enables single stepping. The PC is set to the out-of-line slot address before the ERET. With this scheme, the instruction is executed with the exact same register context except for the PC (and DAIF) registers. Debug mask (PSTATE.D) is enabled only when single stepping a recursive kprobe, e.g.: during kprobes reenter so that probed instruction can be single stepped within the kprobe handler -exception- context. The recursion depth of kprobe is always 2, i.e. upon probe re-entry, any further re-entry is prevented by not calling handlers and the case counted as a missed kprobe). Single stepping from the x-o-l slot has a drawback for PC-relative accesses like branching and symbolic literals access as the offset from the new PC (slot address) may not be ensured to fit in the immediate value of the opcode. Such instructions need simulation, so reject probing them. Instructions generating exceptions or cpu mode change are rejected for probing. Exclusive load/store instructions are rejected too. Additionally, the code is checked to see if it is inside an exclusive load/store sequence (code from Pratyush). System instructions are mostly enabled for stepping, except MSR/MRS accesses to "DAIF" flags in PSTATE, which are not safe for probing. This also changes arch/arm64/include/asm/ptrace.h to use include/asm-generic/ptrace.h. Thanks to Steve Capper and Pratyush Anand for several suggested Changes. Signed-off-by: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com> Signed-off-by: David A. Long <dave.long@linaro.org> Signed-off-by: Pratyush Anand <panand@redhat.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-08 12:35:48 -04:00
#endif
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