mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-23 01:24:47 +07:00
9c0be3f6b5
commit 46e0c9be20 ("kernel: tracepoints: add support for relative
references") changes the layout of the __tracepoint_ptrs section on
architectures supporting relative references. However, it does so
without turning struct tracepoint * const into const int elsewhere in
the tracepoint code, which has the following side-effect:
Setting mod->num_tracepoints is done in by module.c:
mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
sizeof(*mod->tracepoints_ptrs),
&mod->num_tracepoints);
Basically, since sizeof(*mod->tracepoints_ptrs) is a pointer size
(rather than sizeof(int)), num_tracepoints is erroneously set to half the
size it should be on 64-bit arch. So a module with an odd number of
tracepoints misses the last tracepoint due to effect of integer
division.
So in the module going notifier:
for_each_tracepoint_range(mod->tracepoints_ptrs,
mod->tracepoints_ptrs + mod->num_tracepoints,
tp_module_going_check_quiescent, NULL);
the expression (mod->tracepoints_ptrs + mod->num_tracepoints) actually
evaluates to something within the bounds of the array, but miss the
last tracepoint if the number of tracepoints is odd on 64-bit arch.
Fix this by introducing a new typedef: tracepoint_ptr_t, which
is either "const int" on architectures that have PREL32 relocations,
or "struct tracepoint * const" on architectures that does not have
this feature.
Also provide a new tracepoint_ptr_defer() static inline to
encapsulate deferencing this type rather than duplicate code and
ugly idefs within the for_each_tracepoint_range() implementation.
This issue appears in 4.19-rc kernels, and should ideally be fixed
before the end of the rc cycle.
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Link: http://lkml.kernel.org/r/20181013191050.22389-1-mathieu.desnoyers@efficios.com
Link: http://lkml.kernel.org/r/20180704083651.24360-7-ard.biesheuvel@linaro.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morris <james.morris@microsoft.com>
Cc: James Morris <jmorris@namei.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
51 lines
1.0 KiB
C
51 lines
1.0 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef TRACEPOINT_DEFS_H
|
|
#define TRACEPOINT_DEFS_H 1
|
|
|
|
/*
|
|
* File can be included directly by headers who only want to access
|
|
* tracepoint->key to guard out of line trace calls, or the definition of
|
|
* trace_print_flags{_u64}. Otherwise linux/tracepoint.h should be used.
|
|
*/
|
|
|
|
#include <linux/atomic.h>
|
|
#include <linux/static_key.h>
|
|
|
|
struct trace_print_flags {
|
|
unsigned long mask;
|
|
const char *name;
|
|
};
|
|
|
|
struct trace_print_flags_u64 {
|
|
unsigned long long mask;
|
|
const char *name;
|
|
};
|
|
|
|
struct tracepoint_func {
|
|
void *func;
|
|
void *data;
|
|
int prio;
|
|
};
|
|
|
|
struct tracepoint {
|
|
const char *name; /* Tracepoint name */
|
|
struct static_key key;
|
|
int (*regfunc)(void);
|
|
void (*unregfunc)(void);
|
|
struct tracepoint_func __rcu *funcs;
|
|
};
|
|
|
|
#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
|
|
typedef const int tracepoint_ptr_t;
|
|
#else
|
|
typedef struct tracepoint * const tracepoint_ptr_t;
|
|
#endif
|
|
|
|
struct bpf_raw_event_map {
|
|
struct tracepoint *tp;
|
|
void *bpf_func;
|
|
u32 num_args;
|
|
} __aligned(32);
|
|
|
|
#endif
|