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    Subject[PATCH v4 13/16] arm/ftrace: Use __patch_text_real()
    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_*().

    Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
    Cc: ard.biesheuvel@linaro.org
    Cc: rabin@rab.in
    Cc: Mark Rutland <mark.rutland@arm.com>
    Cc: Will Deacon <will@kernel.org>
    Cc: james.morse@arm.com
    ---
    arch/arm/kernel/ftrace.c | 16 ++++++++--------
    1 file changed, 8 insertions(+), 8 deletions(-)

    --- a/arch/arm/kernel/ftrace.c
    +++ b/arch/arm/kernel/ftrace.c
    @@ -22,6 +22,7 @@
    #include <asm/ftrace.h>
    #include <asm/insn.h>
    #include <asm/set_memory.h>
    +#include <asm/patch.h>

    #ifdef CONFIG_THUMB2_KERNEL
    #define NOP 0xf85deb04 /* pop.w {lr} */
    @@ -31,13 +32,15 @@

    #ifdef CONFIG_DYNAMIC_FTRACE

    +static int patch_text_remap = 0;
    +
    static int __ftrace_modify_code(void *data)
    {
    int *command = data;

    - set_kernel_text_rw();
    + patch_text_remap++;
    ftrace_modify_all_code(*command);
    - set_kernel_text_ro();
    + patch_text_remap--;

    return 0;
    }
    @@ -59,13 +62,13 @@ static unsigned long adjust_address(stru

    int ftrace_arch_code_modify_prepare(void)
    {
    - set_all_modules_text_rw();
    + patch_text_remap++;
    return 0;
    }

    int ftrace_arch_code_modify_post_process(void)
    {
    - set_all_modules_text_ro();
    + patch_text_remap--;
    /* Make sure any TLB misses during machine stop are cleared. */
    flush_tlb_all();
    return 0;
    @@ -97,10 +100,7 @@ static int ftrace_modify_code(unsigned l
    return -EINVAL;
    }

    - if (probe_kernel_write((void *)pc, &new, MCOUNT_INSN_SIZE))
    - return -EPERM;
    -
    - flush_icache_range(pc, pc + MCOUNT_INSN_SIZE);
    + __patch_text_real((void *)pc, new, patch_text_remap);

    return 0;
    }

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