linux/arch/x86/kernel/perf_regs.c
Dan Carpenter 1e6dd8adc7 perf: Fix off by one test in perf_reg_value()
The test should be >= ARRAY_SIZE() instead of > ARRAY_SIZE().

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/20120905123126.GC6128@elgon.mountain
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-09-19 17:08:40 +02:00

106 lines
2.5 KiB
C

#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/perf_event.h>
#include <linux/bug.h>
#include <linux/stddef.h>
#include <asm/perf_regs.h>
#include <asm/ptrace.h>
#ifdef CONFIG_X86_32
#define PERF_REG_X86_MAX PERF_REG_X86_32_MAX
#else
#define PERF_REG_X86_MAX PERF_REG_X86_64_MAX
#endif
#define PT_REGS_OFFSET(id, r) [id] = offsetof(struct pt_regs, r)
static unsigned int pt_regs_offset[PERF_REG_X86_MAX] = {
PT_REGS_OFFSET(PERF_REG_X86_AX, ax),
PT_REGS_OFFSET(PERF_REG_X86_BX, bx),
PT_REGS_OFFSET(PERF_REG_X86_CX, cx),
PT_REGS_OFFSET(PERF_REG_X86_DX, dx),
PT_REGS_OFFSET(PERF_REG_X86_SI, si),
PT_REGS_OFFSET(PERF_REG_X86_DI, di),
PT_REGS_OFFSET(PERF_REG_X86_BP, bp),
PT_REGS_OFFSET(PERF_REG_X86_SP, sp),
PT_REGS_OFFSET(PERF_REG_X86_IP, ip),
PT_REGS_OFFSET(PERF_REG_X86_FLAGS, flags),
PT_REGS_OFFSET(PERF_REG_X86_CS, cs),
PT_REGS_OFFSET(PERF_REG_X86_SS, ss),
#ifdef CONFIG_X86_32
PT_REGS_OFFSET(PERF_REG_X86_DS, ds),
PT_REGS_OFFSET(PERF_REG_X86_ES, es),
PT_REGS_OFFSET(PERF_REG_X86_FS, fs),
PT_REGS_OFFSET(PERF_REG_X86_GS, gs),
#else
/*
* The pt_regs struct does not store
* ds, es, fs, gs in 64 bit mode.
*/
(unsigned int) -1,
(unsigned int) -1,
(unsigned int) -1,
(unsigned int) -1,
#endif
#ifdef CONFIG_X86_64
PT_REGS_OFFSET(PERF_REG_X86_R8, r8),
PT_REGS_OFFSET(PERF_REG_X86_R9, r9),
PT_REGS_OFFSET(PERF_REG_X86_R10, r10),
PT_REGS_OFFSET(PERF_REG_X86_R11, r11),
PT_REGS_OFFSET(PERF_REG_X86_R12, r12),
PT_REGS_OFFSET(PERF_REG_X86_R13, r13),
PT_REGS_OFFSET(PERF_REG_X86_R14, r14),
PT_REGS_OFFSET(PERF_REG_X86_R15, r15),
#endif
};
u64 perf_reg_value(struct pt_regs *regs, int idx)
{
if (WARN_ON_ONCE(idx >= ARRAY_SIZE(pt_regs_offset)))
return 0;
return regs_get_register(regs, pt_regs_offset[idx]);
}
#define REG_RESERVED (~((1ULL << PERF_REG_X86_MAX) - 1ULL))
#ifdef CONFIG_X86_32
int perf_reg_validate(u64 mask)
{
if (!mask || mask & REG_RESERVED)
return -EINVAL;
return 0;
}
u64 perf_reg_abi(struct task_struct *task)
{
return PERF_SAMPLE_REGS_ABI_32;
}
#else /* CONFIG_X86_64 */
#define REG_NOSUPPORT ((1ULL << PERF_REG_X86_DS) | \
(1ULL << PERF_REG_X86_ES) | \
(1ULL << PERF_REG_X86_FS) | \
(1ULL << PERF_REG_X86_GS))
int perf_reg_validate(u64 mask)
{
if (!mask || mask & REG_RESERVED)
return -EINVAL;
if (mask & REG_NOSUPPORT)
return -EINVAL;
return 0;
}
u64 perf_reg_abi(struct task_struct *task)
{
if (test_tsk_thread_flag(task, TIF_IA32))
return PERF_SAMPLE_REGS_ABI_32;
else
return PERF_SAMPLE_REGS_ABI_64;
}
#endif /* CONFIG_X86_32 */