powerpc/ftrace: fix syscall tracing on PPC64_ELF_ABI_V1
authorMichael Jeanson <mjeanson@efficios.com>
Thu, 1 Dec 2022 16:14:42 +0000 (11:14 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 7 Jan 2023 10:11:48 +0000 (11:11 +0100)
commit ad050d2390fccb22aa3e6f65e11757ce7a5a7ca5 upstream.

In v5.7 the powerpc syscall entry/exit logic was rewritten in C, on
PPC64_ELF_ABI_V1 this resulted in the symbols in the syscall table
changing from their dot prefixed variant to the non-prefixed ones.

Since ftrace prefixes a dot to the syscall names when matching them to
build its syscall event list, this resulted in no syscall events being
available.

Remove the PPC64_ELF_ABI_V1 specific version of
arch_syscall_match_sym_name to have the same behavior across all powerpc
variants.

Fixes: 68b34588e202 ("powerpc/64/sycall: Implement syscall entry/exit logic in C")
Cc: stable@vger.kernel.org # v5.7+
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221201161442.2127231-1-mjeanson@efficios.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/powerpc/include/asm/ftrace.h

index 3cee7115441b41cb92bbe6230bb5f936edda45c0..e3d1f377bc5b5bbc2a21b429804ffa965d546562 100644 (file)
@@ -64,17 +64,6 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
  * those.
  */
 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
-#ifdef CONFIG_PPC64_ELF_ABI_V1
-static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
-{
-       /* We need to skip past the initial dot, and the __se_sys alias */
-       return !strcmp(sym + 1, name) ||
-               (!strncmp(sym, ".__se_sys", 9) && !strcmp(sym + 6, name)) ||
-               (!strncmp(sym, ".ppc_", 5) && !strcmp(sym + 5, name + 4)) ||
-               (!strncmp(sym, ".ppc32_", 7) && !strcmp(sym + 7, name + 4)) ||
-               (!strncmp(sym, ".ppc64_", 7) && !strcmp(sym + 7, name + 4));
-}
-#else
 static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
 {
        return !strcmp(sym, name) ||
@@ -83,7 +72,6 @@ static inline bool arch_syscall_match_sym_name(const char *sym, const char *name
                (!strncmp(sym, "ppc32_", 6) && !strcmp(sym + 6, name + 4)) ||
                (!strncmp(sym, "ppc64_", 6) && !strcmp(sym + 6, name + 4));
 }
-#endif /* CONFIG_PPC64_ELF_ABI_V1 */
 #endif /* CONFIG_FTRACE_SYSCALLS */
 
 #if defined(CONFIG_PPC64) && defined(CONFIG_FUNCTION_TRACER)