[PATCH 2/9] x86, perf: Fix incorrect TIF_IA32 check in code_segment_base

From: Andy Lutomirski
Date: Wed Mar 18 2015 - 21:35:10 EST


We're want to check whether user code is in 32-bit mode, not whether
the task is nominally 32-bit.

Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
---
arch/x86/kernel/cpu/perf_event.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index b71a7f86d68a..979963bb3977 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -2161,10 +2161,9 @@ static unsigned long code_segment_base(struct pt_regs *regs)
if (user_mode(regs) && regs->cs != __USER_CS)
return get_segment_base(regs->cs);
#else
- if (test_thread_flag(TIF_IA32)) {
- if (user_mode(regs) && regs->cs != __USER32_CS)
- return get_segment_base(regs->cs);
- }
+ if (user_mode(regs) && !user_64bit_mode(regs) &&
+ regs->cs != __USER32_CS)
+ return get_segment_base(regs->cs);
#endif
return 0;
}
--
2.3.0

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