[PATCH v3 01/10] x86: events: Avoid TIF_IA32 when checking 64bit mode

From: Gabriel Krisman Bertazi
Date: Sat Oct 03 2020 - 23:26:08 EST


In preparation to remove TIF_IA32, stop using it in perf events code.

Tested by running perf on 32-bit, 64-bit and x32 applications.

Suggested-by: Andy Lutomirski <luto@xxxxxxxxxx>
Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/x86/events/core.c | 2 +-
arch/x86/events/intel/ds.c | 2 +-
arch/x86/events/intel/lbr.c | 2 +-
arch/x86/kernel/perf_regs.c | 2 +-
4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 1cbf57dc2ac8..4fe82d9d959b 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -2499,7 +2499,7 @@ perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry_ctx *ent
struct stack_frame_ia32 frame;
const struct stack_frame_ia32 __user *fp;

- if (!test_thread_flag(TIF_IA32))
+ if (user_64bit_mode(regs))
return 0;

cs_base = get_segment_base(regs->cs);
diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index 86848c57b55e..94bd0d3acd15 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -1261,7 +1261,7 @@ static int intel_pmu_pebs_fixup_ip(struct pt_regs *regs)
old_to = to;

#ifdef CONFIG_X86_64
- is_64bit = kernel_ip(to) || !test_thread_flag(TIF_IA32);
+ is_64bit = kernel_ip(to) || any_64bit_mode(regs);
#endif
insn_init(&insn, kaddr, size, is_64bit);
insn_get_length(&insn);
diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c
index 8961653c5dd2..1aadb253d296 100644
--- a/arch/x86/events/intel/lbr.c
+++ b/arch/x86/events/intel/lbr.c
@@ -1221,7 +1221,7 @@ static int branch_type(unsigned long from, unsigned long to, int abort)
* on 64-bit systems running 32-bit apps
*/
#ifdef CONFIG_X86_64
- is64 = kernel_ip((unsigned long)addr) || !test_thread_flag(TIF_IA32);
+ is64 = kernel_ip((unsigned long)addr) || any_64bit_mode(current_pt_regs());
#endif
insn_init(&insn, addr, bytes_read, is64);
insn_get_opcode(&insn);
diff --git a/arch/x86/kernel/perf_regs.c b/arch/x86/kernel/perf_regs.c
index bb7e1132290b..9332c49a64a8 100644
--- a/arch/x86/kernel/perf_regs.c
+++ b/arch/x86/kernel/perf_regs.c
@@ -123,7 +123,7 @@ int perf_reg_validate(u64 mask)

u64 perf_reg_abi(struct task_struct *task)
{
- if (test_tsk_thread_flag(task, TIF_IA32))
+ if (!user_64bit_mode(task_pt_regs(task)))
return PERF_SAMPLE_REGS_ABI_32;
else
return PERF_SAMPLE_REGS_ABI_64;
--
2.28.0