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McKenney" , Jinjie Ruan , Arnd Bergmann , Ard Biesheuvel , Al Viro Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Linus Walleij X-Mailer: b4 0.14.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241010_043431_019226_4E9A422E X-CRM114-Status: GOOD ( 28.04 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org This rewrites ARM to use the generic entry. All of the irqentry_* callbacks are renamed to arm_irqentry_* and made to call into the generic entry code. The state for IRQ and NMI for usermode and kernelmode is stored into a static local variable as interrupts are not reentrant. The syscall_enter_from_user_mode(), syscall_exit_to_user_mode(), do_work_pending() constructs are replaced with generic code. The syscall invocation now enables syscall tracing "work" using the generic callbacks and no extra actions are needed to enable/disable syscall tracing. The old context tracking with user_exit_callable() user_enter_callable() is no longer used. Only CSKY and Xtensa use this deprecated mechanism now. Like with the ARM64 proposed patch for generic entry, it is necessary to create a small call "arm_exit_to_user_mode()" that is used for things such as ret_from_fork, i.e. when we create a completely new execution context with a botched return from interrupt. Open questions: - I had to add defines for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP and I have no idea what those are or why they are required. Sorry for my ignorance, I need help to figure out how we deal with this. Signed-off-by: Linus Walleij --- arch/arm/Kconfig | 1 + arch/arm/include/asm/entry-common.h | 66 +++++++++++++++++++++++++++ arch/arm/include/asm/entry.h | 23 ++++------ arch/arm/include/asm/ptrace.h | 3 -- arch/arm/include/asm/signal.h | 2 - arch/arm/include/asm/syscall.h | 7 ++- arch/arm/include/asm/thread_info.h | 17 +------ arch/arm/include/uapi/asm/ptrace.h | 2 + arch/arm/kernel/entry-armv.S | 8 ++-- arch/arm/kernel/entry-common.S | 34 +++++--------- arch/arm/kernel/entry-header.S | 8 ++-- arch/arm/kernel/entry.c | 80 +++++++++++---------------------- arch/arm/kernel/process.c | 2 - arch/arm/kernel/ptrace.c | 90 ------------------------------------- arch/arm/kernel/signal.c | 31 +------------ arch/arm/kernel/syscall.c | 27 +++-------- 16 files changed, 137 insertions(+), 264 deletions(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 749179a1d162..8155a4be7c9b 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -66,6 +66,7 @@ config ARM select GENERIC_CPU_AUTOPROBE select GENERIC_CPU_DEVICES select GENERIC_EARLY_IOREMAP + select GENERIC_ENTRY select GENERIC_IDLE_POLL_SETUP select GENERIC_IRQ_MULTI_HANDLER select GENERIC_IRQ_PROBE diff --git a/arch/arm/include/asm/entry-common.h b/arch/arm/include/asm/entry-common.h new file mode 100644 index 000000000000..7b1f108512db --- /dev/null +++ b/arch/arm/include/asm/entry-common.h @@ -0,0 +1,66 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _ASM_ARM_ENTRY_COMMON_H +#define _ASM_ARM_ENTRY_COMMON_H + +#include + +#include + +enum ptrace_syscall_dir { + PTRACE_SYSCALL_ENTER = 0, + PTRACE_SYSCALL_EXIT, +}; + +static inline unsigned long +arch_prepare_report_syscall_entry(struct pt_regs *regs) +{ + unsigned long ip; + + /* + * IP is used to denote syscall entry/exit: + * IP = 0 -> entry + */ + ip = regs->ARM_ip; + regs->ARM_ip = PTRACE_SYSCALL_ENTER; + + return ip; +} +#define arch_prepare_report_syscall_entry arch_prepare_report_syscall_entry + +static inline void +arch_post_report_syscall_entry(struct pt_regs *regs, + unsigned long saved_reg, long ret) +{ + regs->ARM_ip = saved_reg; +} +#define arch_post_report_syscall_entry arch_post_report_syscall_entry + + +static inline unsigned long +arch_prepare_report_syscall_exit(struct pt_regs *regs, + unsigned long work) +{ + unsigned long ip; + + /* + * IP is used to denote syscall entry/exit: + * IP = 1 -> exit + */ + ip = regs->ARM_ip; + regs->ARM_ip = PTRACE_SYSCALL_EXIT; + + return ip; +} +#define arch_prepare_report_syscall_exit arch_prepare_report_syscall_exit + +static inline void +arch_post_report_syscall_exit(struct pt_regs *regs, + unsigned long saved_reg, + unsigned long work) +{ + regs->ARM_ip = saved_reg; +} +#define arch_post_report_syscall_exit arch_post_report_syscall_exit + +#endif /* _ASM_ARM_ENTRY_COMMON_H */ diff --git a/arch/arm/include/asm/entry.h b/arch/arm/include/asm/entry.h index 2e7ccd87f0eb..dadf0064c65b 100644 --- a/arch/arm/include/asm/entry.h +++ b/arch/arm/include/asm/entry.h @@ -4,19 +4,14 @@ struct pt_regs; -/* - * These are copies of generic entry headers so we can transition - * to generic entry once they are semantically equivalent. - */ -long syscall_enter_from_user_mode(struct pt_regs *regs, long); -void syscall_exit_to_user_mode(struct pt_regs *regs); -void irqentry_enter_from_user_mode(struct pt_regs *regs); -void irqentry_exit_to_user_mode(struct pt_regs *regs); -void irqentry_enter_from_kernel_mode(struct pt_regs *regs); -void irqentry_exit_to_kernel_mode(struct pt_regs *regs); -void irqentry_nmi_enter_from_user_mode(struct pt_regs *regs); -void irqentry_nmi_exit_to_user_mode(struct pt_regs *regs); -void irqentry_nmi_enter_from_kernel_mode(struct pt_regs *regs); -void irqentry_nmi_exit_to_kernel_mode(struct pt_regs *regs); +void arm_irqentry_enter_from_user_mode(struct pt_regs *regs); +void arm_irqentry_exit_to_user_mode(struct pt_regs *regs); +void arm_irqentry_enter_from_kernel_mode(struct pt_regs *regs); +void arm_irqentry_exit_to_kernel_mode(struct pt_regs *regs); +void arm_irqentry_nmi_enter_from_user_mode(struct pt_regs *regs); +void arm_irqentry_nmi_exit_to_user_mode(struct pt_regs *regs); +void arm_irqentry_nmi_enter_from_kernel_mode(struct pt_regs *regs); +void arm_irqentry_nmi_exit_to_kernel_mode(struct pt_regs *regs); +void arm_exit_to_user_mode(struct pt_regs *regs); #endif /* __ASM_ENTRY_H__ */ diff --git a/arch/arm/include/asm/ptrace.h b/arch/arm/include/asm/ptrace.h index a01c66f0ad90..8a7de4020cbc 100644 --- a/arch/arm/include/asm/ptrace.h +++ b/arch/arm/include/asm/ptrace.h @@ -200,8 +200,5 @@ static inline unsigned long it_advance(unsigned long cpsr) return cpsr; } -int syscall_trace_enter(struct pt_regs *regs); -void syscall_trace_exit(struct pt_regs *regs); - #endif /* __ASSEMBLY__ */ #endif diff --git a/arch/arm/include/asm/signal.h b/arch/arm/include/asm/signal.h index bb753cd3e29f..45885383646c 100644 --- a/arch/arm/include/asm/signal.h +++ b/arch/arm/include/asm/signal.h @@ -23,6 +23,4 @@ typedef struct { #include -void do_work_pending(struct pt_regs *regs, unsigned int thread_flags); - #endif diff --git a/arch/arm/include/asm/syscall.h b/arch/arm/include/asm/syscall.h index b94fd7ce17f8..a6c8f0e799bb 100644 --- a/arch/arm/include/asm/syscall.h +++ b/arch/arm/include/asm/syscall.h @@ -19,7 +19,12 @@ extern const unsigned long sys_call_table[]; -int invoke_syscall(void *table, struct pt_regs *regs, int scno); +void invoke_syscall(void *table, struct pt_regs *regs, int scno); + +static inline bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs) +{ + return false; +} static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs) diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h index d8a45c5a1049..84e58a9cdab6 100644 --- a/arch/arm/include/asm/thread_info.h +++ b/arch/arm/include/asm/thread_info.h @@ -74,6 +74,7 @@ struct thread_info { #ifdef CONFIG_ARM_THUMBEE unsigned long thumbee_state; /* ThumbEE Handler Base register */ #endif + unsigned long syscall_work; /* SYSCALL_WORK_ flags */ }; #define INIT_THREAD_INFO(tsk) \ @@ -149,30 +150,14 @@ extern int vfp_restore_user_hwstate(struct user_vfp *, #define TIF_USING_IWMMXT 17 #define TIF_MEMDIE 18 /* is terminating due to OOM killer */ #define TIF_RESTORE_SIGMASK 19 -#define TIF_SYSCALL_TRACE 20 /* syscall trace active */ -#define TIF_SYSCALL_AUDIT 21 /* syscall auditing active */ -#define TIF_SYSCALL_TRACEPOINT 22 /* syscall tracepoint instrumentation */ -#define TIF_SECCOMP 23 /* seccomp syscall filtering active */ - #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) #define _TIF_UPROBE (1 << TIF_UPROBE) -#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) -#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) -#define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) -#define _TIF_SECCOMP (1 << TIF_SECCOMP) #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL) #define _TIF_USING_IWMMXT (1 << TIF_USING_IWMMXT) -/* Checks for any syscall work in entry-common.S */ -#define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ - _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP) - -/* - * Change these and you break ASM code in entry-common.S - */ #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ _TIF_NOTIFY_RESUME | _TIF_UPROBE | \ _TIF_NOTIFY_SIGNAL) diff --git a/arch/arm/include/uapi/asm/ptrace.h b/arch/arm/include/uapi/asm/ptrace.h index 8896c23ccba7..336a5beb282f 100644 --- a/arch/arm/include/uapi/asm/ptrace.h +++ b/arch/arm/include/uapi/asm/ptrace.h @@ -33,6 +33,8 @@ #define PTRACE_GETHBPREGS 29 #define PTRACE_SETHBPREGS 30 #define PTRACE_GETFDPIC 31 +#define PTRACE_SYSEMU 32 +#define PTRACE_SYSEMU_SINGLESTEP 33 #define PTRACE_GETFDPIC_EXEC 0 #define PTRACE_GETFDPIC_INTERP 1 diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index 839f3ebe7228..1bbadf13136e 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -206,9 +206,9 @@ ENDPROC(__und_invalid) mov r0, sp @ 'regs' .if \nmi - bl irqentry_nmi_enter_from_kernel_mode + bl arm_irqentry_nmi_enter_from_kernel_mode .else - bl irqentry_enter_from_kernel_mode + bl arm_irqentry_enter_from_kernel_mode .endif .endm @@ -495,12 +495,12 @@ ENDPROC(ret_from_exception) __fiq_usr: usr_entry mov r0, sp - bl irqentry_nmi_enter_from_user_mode + bl arm_irqentry_nmi_enter_from_user_mode kuser_cmpxchg_check mov r0, sp @ struct pt_regs *regs bl handle_fiq_as_nmi mov r0, sp - bl irqentry_nmi_exit_to_user_mode + bl arm_irqentry_nmi_exit_to_user_mode get_thread_info tsk restore_user_regs UNWIND(.fnend ) diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 6b0f86786a7d..b3b2455ab0a1 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -39,10 +39,6 @@ ret_fast_syscall: UNWIND(.fnstart ) UNWIND(.cantunwind ) add sp, sp, #(S_R0 + S_OFF) - /* do_rseq_syscall needs interrupts enabled. */ - mov r0, sp @ 'regs' - bl syscall_exit_to_user_mode - #ifdef CONFIG_GCC_PLUGIN_STACKLEAK bl stackleak_erase_on_task_stack #endif @@ -60,7 +56,7 @@ ENTRY(ret_to_user) /* do_rseq_syscall needs interrupts enabled. */ enable_irq_notrace @ enable interrupts mov r0, sp @ 'regs' - bl syscall_exit_to_user_mode + bl arm_exit_to_user_mode #ifdef CONFIG_GCC_PLUGIN_STACKLEAK bl stackleak_erase_on_task_stack @@ -94,7 +90,14 @@ SYM_TYPED_FUNC_START(ret_from_fork_asm) bl ret_from_fork mov r0, #0 1: get_thread_info tsk - b ret_to_user + enable_irq_notrace @ enable interrupts + mov r0, sp @ 'regs' + bl syscall_exit_to_user_mode + +#ifdef CONFIG_GCC_PLUGIN_STACKLEAK + bl stackleak_erase_on_task_stack +#endif + restore_user_regs SYM_FUNC_END(ret_from_fork_asm) /*============================================================================= @@ -210,29 +213,12 @@ ENTRY(vector_swi) #else str scno, [tsk, #TI_ABI_SYSCALL] #endif - - /* - * Calling out to C to be careful to save and restore registers. - * This call could modify the syscall number. scno is r7 so we - * do not save and restore r7. - */ - mov r0, sp @ regs - mov r1, scno - push {r4 - r6, r8 - r10, lr} - bl syscall_enter_from_user_mode - pop {r4 - r6, r8 - r10, lr} - mov scno, r0 - mov r1, sp @ put regs into r1 stmdb sp!, {r4, r5} @ push fifth and sixth args mov r0, tbl mov r2, scno @ syscall number from r7 bl invoke_syscall - cmp r0, #0 - beq ret_fast_syscall - /* This path taken when tracing */ - add sp, sp, #(S_R0 + S_OFF) - b ret_to_user + b ret_fast_syscall #if defined(CONFIG_OABI_COMPAT) || !defined(CONFIG_AEABI) /* diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S index ec8a6e193802..b5d61b871dec 100644 --- a/arch/arm/kernel/entry-header.S +++ b/arch/arm/kernel/entry-header.S @@ -205,7 +205,7 @@ disable_irq_notrace mov r0, sp @ 'regs' - bl irqentry_exit_to_kernel_mode + bl arm_irqentry_exit_to_kernel_mode uaccess_exit tsk, r0, r1 @@ -253,7 +253,7 @@ .macro svc_exit_via_fiq uaccess_exit tsk, r0, r1 mov r0, sp - bl irqentry_nmi_exit_to_kernel_mode + bl arm_irqentry_nmi_exit_to_kernel_mode #ifndef CONFIG_THUMB2_KERNEL @ ARM mode restore mov r0, sp @@ -348,12 +348,12 @@ ALT_UP_B(.L1_\@) */ .macro asm_irqentry_enter_from_user_mode mov r0, sp @ regs - bl irqentry_enter_from_user_mode + bl arm_irqentry_enter_from_user_mode .endm .macro asm_irqentry_exit_to_user_mode mov r0, sp @ regs - bl irqentry_exit_to_user_mode + bl arm_irqentry_exit_to_user_mode .endm /* diff --git a/arch/arm/kernel/entry.c b/arch/arm/kernel/entry.c index 09109215dfdf..7302ed8025a9 100644 --- a/arch/arm/kernel/entry.c +++ b/arch/arm/kernel/entry.c @@ -1,87 +1,59 @@ // SPDX-License-Identifier: GPL-2.0 #include -#include -#include #include +#include #include #include -long syscall_enter_from_user_mode(struct pt_regs *regs, long syscall) -{ - trace_hardirqs_on(); - local_irq_enable(); - /* This context tracking call has inverse naming */ - user_exit_callable(); - - /* This will optionally be modified later */ - return syscall; -} +static irqentry_state_t user_irq_state; +static irqentry_state_t kernel_irq_state; +static irqentry_state_t user_nmi_state; +static irqentry_state_t kernel_nmi_state; -void syscall_exit_to_user_mode(struct pt_regs *regs) +noinstr void arm_irqentry_enter_from_user_mode(struct pt_regs *regs) { - unsigned long flags = read_thread_flags(); - - rseq_syscall(regs); - local_irq_disable(); - /* - * It really matters that we check for flags != 0 and not - * just for pending work here! - */ - if (flags) - do_work_pending(regs, flags); - - trace_hardirqs_on(); - /* This context tracking call has inverse naming */ - user_enter_callable(); + user_irq_state = irqentry_enter(regs); } -noinstr void irqentry_enter_from_user_mode(struct pt_regs *regs) +noinstr void arm_irqentry_exit_to_user_mode(struct pt_regs *regs) { - trace_hardirqs_off(); - /* This context tracking call has inverse naming */ - user_exit_callable(); + irqentry_exit(regs, user_irq_state); } -noinstr void irqentry_exit_to_user_mode(struct pt_regs *regs) +noinstr void arm_irqentry_enter_from_kernel_mode(struct pt_regs *regs) { - unsigned long flags = read_thread_flags(); - - /* - * It really matters that we check for flags != 0 and not - * just for pending work here! - */ - if (flags) - do_work_pending(regs, flags); - trace_hardirqs_on(); - /* This context tracking call has inverse naming */ - user_enter_callable(); + kernel_irq_state = irqentry_enter(regs); } -noinstr void irqentry_enter_from_kernel_mode(struct pt_regs *regs) +noinstr void arm_irqentry_exit_to_kernel_mode(struct pt_regs *regs) { - trace_hardirqs_off(); + irqentry_exit(regs, kernel_irq_state); } -noinstr void irqentry_exit_to_kernel_mode(struct pt_regs *regs) +noinstr void arm_irqentry_nmi_enter_from_user_mode(struct pt_regs *regs) { - if (interrupts_enabled(regs)) - trace_hardirqs_on(); - else - trace_hardirqs_off(); + irqentry_enter_from_user_mode(regs); + user_nmi_state = irqentry_nmi_enter(regs); } -noinstr void irqentry_nmi_enter_from_user_mode(struct pt_regs *regs) +noinstr void arm_irqentry_nmi_exit_to_user_mode(struct pt_regs *regs) { + irqentry_nmi_exit(regs, user_nmi_state); + irqentry_exit_to_user_mode(regs); } -noinstr void irqentry_nmi_exit_to_user_mode(struct pt_regs *regs) +noinstr void arm_irqentry_nmi_enter_from_kernel_mode(struct pt_regs *regs) { + kernel_nmi_state = irqentry_nmi_enter(regs); } -noinstr void irqentry_nmi_enter_from_kernel_mode(struct pt_regs *regs) +noinstr void arm_irqentry_nmi_exit_to_kernel_mode(struct pt_regs *regs) { + irqentry_nmi_exit(regs, kernel_nmi_state); } -noinstr void irqentry_nmi_exit_to_kernel_mode(struct pt_regs *regs) +asmlinkage void arm_exit_to_user_mode(struct pt_regs *regs) { + local_irq_disable(); + irqentry_exit_to_user_mode(regs); } diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 81c1c3f98834..6c525a33fa6d 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -248,8 +248,6 @@ __visible void ret_from_fork(struct task_struct *prev, struct pt_regs *regs, * execve() syscall. */ } - - /* syscall_exit_to_user_mode(regs); here once we switch to generic entry */ } int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c index ac7b98ae4724..89afe714cedc 100644 --- a/arch/arm/kernel/ptrace.c +++ b/arch/arm/kernel/ptrace.c @@ -27,9 +27,6 @@ #include #include -#define CREATE_TRACE_POINTS -#include - #define REG_PC 15 #define REG_PSR 16 /* @@ -821,90 +818,3 @@ long arch_ptrace(struct task_struct *child, long request, return ret; } - -enum ptrace_syscall_dir { - PTRACE_SYSCALL_ENTER = 0, - PTRACE_SYSCALL_EXIT, -}; - -static void report_syscall_enter(struct pt_regs *regs) -{ - unsigned long ip; - - /* - * IP is used to denote syscall entry/exit: - * IP = 0 -> entry - */ - ip = regs->ARM_ip; - regs->ARM_ip = PTRACE_SYSCALL_ENTER; - - if (ptrace_report_syscall_entry(regs)) - current_thread_info()->abi_syscall = -1; - - regs->ARM_ip = ip; -} - -static void report_syscall_exit(struct pt_regs *regs) -{ - unsigned long ip; - - /* - * IP is used to denote syscall entry/exit: - * IP = 1 -> exit - */ - ip = regs->ARM_ip; - regs->ARM_ip = PTRACE_SYSCALL_EXIT; - - ptrace_report_syscall_exit(regs, 0); - - regs->ARM_ip = ip; -} - -asmlinkage int syscall_trace_enter(struct pt_regs *regs) -{ - int scno; - - if (test_thread_flag(TIF_SYSCALL_TRACE)) - report_syscall_enter(regs); - - /* Do seccomp after ptrace; syscall may have changed. */ -#ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER - if (secure_computing() == -1) - return -1; -#else - /* XXX: remove this once OABI gets fixed */ - secure_computing_strict(syscall_get_nr(current, regs)); -#endif - - /* Tracer or seccomp may have changed syscall. */ - scno = syscall_get_nr(current, regs); - - if (test_thread_flag(TIF_SYSCALL_TRACEPOINT)) - trace_sys_enter(regs, scno); - - audit_syscall_entry(scno, regs->ARM_r0, regs->ARM_r1, regs->ARM_r2, - regs->ARM_r3); - - return scno; -} - -void syscall_trace_exit(struct pt_regs *regs) -{ - /* - * Audit the syscall before anything else, as a debugger may - * come in and change the current registers. - */ - audit_syscall_exit(regs); - - /* - * Note that we haven't updated the ->syscall field for the - * current thread. This isn't a problem because it will have - * been set on syscall entry and there hasn't been an opportunity - * for a PTRACE_SET_SYSCALL since then. - */ - if (test_thread_flag(TIF_SYSCALL_TRACEPOINT)) - trace_sys_exit(regs, regs_return_value(regs)); - - if (test_thread_flag(TIF_SYSCALL_TRACE)) - report_syscall_exit(regs); -} diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index a39ee14ec5b7..35d2bb3cd2b4 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -4,6 +4,7 @@ * * Copyright (C) 1995-2009 Russell King */ +#include #include #include #include @@ -535,7 +536,7 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) * the kernel can handle, and then we build all the user-level signal handling * stack-frames in one go after that. */ -static void arch_do_signal_or_restart(struct pt_regs *regs) +void arch_do_signal_or_restart(struct pt_regs *regs) { unsigned int retval = 0, continue_addr = 0, restart_addr = 0; bool syscall = (syscall_get_nr(current, regs) != -1); @@ -598,34 +599,6 @@ static void arch_do_signal_or_restart(struct pt_regs *regs) return; } -void do_work_pending(struct pt_regs *regs, unsigned int thread_flags) -{ - /* - * The assembly code enters us with IRQs off, but it hasn't - * informed the tracing code of that for efficiency reasons. - * Update the trace code with the current status. - */ - trace_hardirqs_off(); - do { - if (likely(thread_flags & _TIF_NEED_RESCHED)) { - schedule(); - } else { - if (unlikely(!user_mode(regs))) - return; - local_irq_enable(); - if (thread_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) { - arch_do_signal_or_restart(regs); - } else if (thread_flags & _TIF_UPROBE) { - uprobe_notify_resume(regs); - } else { - resume_user_mode_work(regs); - } - } - local_irq_disable(); - thread_flags = read_thread_flags(); - } while (thread_flags & _TIF_WORK_MASK); -} - struct page *get_signal_page(void) { unsigned long ptr; diff --git a/arch/arm/kernel/syscall.c b/arch/arm/kernel/syscall.c index 968cec945a7e..26ec3a151652 100644 --- a/arch/arm/kernel/syscall.c +++ b/arch/arm/kernel/syscall.c @@ -1,25 +1,16 @@ // SPDX-License-Identifier: GPL-2.0 +#include #include #include -static inline bool has_syscall_work(unsigned long flags) -{ - return unlikely(flags & _TIF_SYSCALL_WORK); -} - int invoke_syscall_asm(void *table, struct pt_regs *regs, int scno); -__visible int invoke_syscall(void *table, struct pt_regs *regs, int scno) +__visible void invoke_syscall(void *table, struct pt_regs *regs, int scno) { - unsigned long flags = read_thread_flags(); int ret; - if (has_syscall_work(flags)) { - scno = syscall_trace_enter(regs); - if (scno == -1) - goto trace_exit_nosave; - } + scno = syscall_enter_from_user_mode(regs, scno); if (scno < NR_syscalls) { ret = invoke_syscall_asm(table, regs, scno); @@ -34,13 +25,7 @@ __visible int invoke_syscall(void *table, struct pt_regs *regs, int scno) ret = sys_ni_syscall(); exit_save: - /* Save return value from syscall */ - regs->ARM_r0 = ret; - if (!has_syscall_work(flags)) - return 0; - -trace_exit_nosave: - local_irq_enable(); - syscall_trace_exit(regs); - return 1; + syscall_set_return_value(current, regs, 0, ret); + + syscall_exit_to_user_mode(regs); }