Commit 84ade0a6 authored by Naveen N. Rao's avatar Naveen N. Rao Committed by Michael Ellerman
Browse files

powerpc/ftrace: Remove ftrace init tramp once kernel init is complete 



Stop using the ftrace trampoline for init section once kernel init is
complete.

Fixes: 67361cf8 ("powerpc/ftrace: Handle large kernel configs")
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: default avatarNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220516071422.463738-1-naveen.n.rao@linux.vnet.ibm.com
parent 5fe85516

arch/powerpc/include/asm/ftrace.h

+3 −1
Original line number Diff line number Diff line
@@ -86,7 +86,7 @@ static inline bool arch_syscall_match_sym_name(const char *sym, const char *name 
#endif /* CONFIG_PPC64_ELF_ABI_V1 */

#endif /* CONFIG_FTRACE_SYSCALLS */



#ifdef CONFIG_PPC64

#if defined(CONFIG_PPC64) && defined(CONFIG_FUNCTION_TRACER)

#include <asm/paca.h>



static inline void this_cpu_disable_ftrace(void)
@@ -110,11 +110,13 @@ static inline u8 this_cpu_get_ftrace_enabled(void) 
	return get_paca()->ftrace_enabled;

}



void ftrace_free_init_tramp(void);

#else /* CONFIG_PPC64 */

static inline void this_cpu_disable_ftrace(void) { }

static inline void this_cpu_enable_ftrace(void) { }

static inline void this_cpu_set_ftrace_enabled(u8 ftrace_enabled) { }

static inline u8 this_cpu_get_ftrace_enabled(void) { return 1; }

static inline void ftrace_free_init_tramp(void) { }

#endif /* CONFIG_PPC64 */

#endif /* !__ASSEMBLY__ */

arch/powerpc/kernel/trace/ftrace.c

+12 −3
Original line number Diff line number Diff line
@@ -257,9 +257,7 @@ static int setup_mcount_compiler_tramp(unsigned long tramp) 


	/* Is this a known long jump tramp? */

	for (i = 0; i < NUM_FTRACE_TRAMPS; i++)

		if (!ftrace_tramps[i])

			break;

		else if (ftrace_tramps[i] == tramp)

		if (ftrace_tramps[i] == tramp)

			return 0;



	/* New trampoline -- read where this goes */
@@ -710,6 +708,17 @@ void arch_ftrace_update_code(int command) 


extern unsigned int ftrace_tramp_text[], ftrace_tramp_init[];



void ftrace_free_init_tramp(void)

{

	int i;



	for (i = 0; i < NUM_FTRACE_TRAMPS && ftrace_tramps[i]; i++)

		if (ftrace_tramps[i] == (unsigned long)ftrace_tramp_init) {

			ftrace_tramps[i] = 0;

			return;

		}

}



int __init ftrace_dyn_arch_init(void)

{

	int i;

arch/powerpc/mm/mem.c

+2 −0
Original line number Diff line number Diff line
@@ -22,6 +22,7 @@ 
#include <asm/kasan.h>

#include <asm/svm.h>

#include <asm/mmzone.h>

#include <asm/ftrace.h>

#include <asm/code-patching.h>



#include <mm/mmu_decl.h>
@@ -314,6 +315,7 @@ void free_initmem(void) 
	mark_initmem_nx();

	static_branch_enable(&init_mem_is_free);

	free_initmem_default(POISON_FREE_INITMEM);

	ftrace_free_init_tramp();

}



/*