Patch "perf/x86: Avoid TIF_IA32 when checking 64bit mode" has been added to the 5.10-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    perf/x86: Avoid TIF_IA32 when checking 64bit mode

to the 5.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     perf-x86-avoid-tif_ia32-when-checking-64bit-mode.patch
and it can be found in the queue-5.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 1757c2e8b089fd9dccf96b0e0cdf34c8600d7da6
Author: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
Date:   Sat Oct 3 23:25:27 2020 -0400

    perf/x86: Avoid TIF_IA32 when checking 64bit mode
    
    [ Upstream commit 375d4bfda57392f0865dae051e1c4bd2700e8d71 ]
    
    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>
    Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
    Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
    Link: https://lore.kernel.org/r/20201004032536.1229030-2-krisman@xxxxxxxxxxxxx
    Stable-dep-of: 7fea700e04bd ("zap_pid_ns_processes: clear TIF_NOTIFY_SIGNAL along with TIF_SIGPENDING")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index b79b9f21cbb3b..1cef0ceb6acb3 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -2615,7 +2615,7 @@ 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 48f30ffef1f4b..64a847eead484 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -1266,7 +1266,7 @@ 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 4b6c39c5facba..d93076c18c6ca 100644
--- a/arch/x86/events/intel/lbr.c
+++ b/arch/x86/events/intel/lbr.c
@@ -1245,7 +1245,7 @@ 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 f9e5352b3bef9..624703af80a19 100644
--- a/arch/x86/kernel/perf_regs.c
+++ b/arch/x86/kernel/perf_regs.c
@@ -122,7 +122,7 @@ 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;