From 5a735583b764750726621b0396d03e4782911b77 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 15 Oct 2019 21:07:35 +0200 Subject: arm/ftrace: Use __patch_text() Instead of flipping text protection, use the patch_text infrastructure that uses a fixmap alias where required. This removes the last user of set_all_modules_text_*(). Tested-by: Will Deacon Signed-off-by: Peter Zijlstra (Intel) Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Mark Rutland Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: ard.biesheuvel@linaro.org Cc: james.morse@arm.com Cc: rabin@rab.in Link: https://lkml.kernel.org/r/20191113092636.GG4131@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar --- arch/arm/kernel/Makefile | 4 ++-- arch/arm/kernel/ftrace.c | 10 ++-------- 2 files changed, 4 insertions(+), 10 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 8cad59465af3..a885172e504c 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -49,8 +49,8 @@ obj-$(CONFIG_HAVE_ARM_SCU) += smp_scu.o obj-$(CONFIG_HAVE_ARM_TWD) += smp_twd.o obj-$(CONFIG_ARM_ARCH_TIMER) += arch_timer.o obj-$(CONFIG_FUNCTION_TRACER) += entry-ftrace.o -obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o insn.o -obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o insn.o +obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o insn.o patch.o +obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o insn.o patch.o obj-$(CONFIG_JUMP_LABEL) += jump_label.o insn.o patch.o obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o # Main staffs in KPROBES are in arch/arm/probes/ . diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c index bda949fd84e8..2a5ff69c28e6 100644 --- a/arch/arm/kernel/ftrace.c +++ b/arch/arm/kernel/ftrace.c @@ -22,6 +22,7 @@ #include #include #include +#include #ifdef CONFIG_THUMB2_KERNEL #define NOP 0xf85deb04 /* pop.w {lr} */ @@ -35,9 +36,7 @@ static int __ftrace_modify_code(void *data) { int *command = data; - set_kernel_text_rw(); ftrace_modify_all_code(*command); - set_kernel_text_ro(); return 0; } @@ -59,13 +58,11 @@ static unsigned long adjust_address(struct dyn_ftrace *rec, unsigned long addr) int ftrace_arch_code_modify_prepare(void) { - set_all_modules_text_rw(); return 0; } int ftrace_arch_code_modify_post_process(void) { - set_all_modules_text_ro(); /* Make sure any TLB misses during machine stop are cleared. */ flush_tlb_all(); return 0; @@ -97,10 +94,7 @@ static int ftrace_modify_code(unsigned long pc, unsigned long old, return -EINVAL; } - if (probe_kernel_write((void *)pc, &new, MCOUNT_INSN_SIZE)) - return -EPERM; - - flush_icache_range(pc, pc + MCOUNT_INSN_SIZE); + __patch_text((void *)pc, new); return 0; } -- cgit v1.2.3