diff options
| author | Mark Rutland <mark.rutland@arm.com> | 2021-11-29 16:06:52 +0300 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2021-12-01 02:06:44 +0300 |
| commit | 985faa78687de6e583cfd8b8094d87dcb80c33a6 (patch) | |
| tree | c0b6f83c475b2410eba14d3dbd7738296a8c4098 /arch/powerpc/kernel/ptrace | |
| parent | 08b0af5b2affbe7419853e8dd1330e4b3fe27125 (diff) | |
| download | linux-985faa78687de6e583cfd8b8094d87dcb80c33a6.tar.xz | |
powerpc: Snapshot thread flags
Some thread flags can be set remotely, and so even when IRQs are disabled,
the flags can change under our feet. Generally this is unlikely to cause a
problem in practice, but it is somewhat unsound, and KCSAN will
legitimately warn that there is a data race.
To avoid such issues, a snapshot of the flags has to be taken prior to
using them. Some places already use READ_ONCE() for that, others do not.
Convert them all to the new flag accessor helpers.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Link: https://lore.kernel.org/r/20211129130653.2037928-11-mark.rutland@arm.com
Diffstat (limited to 'arch/powerpc/kernel/ptrace')
| -rw-r--r-- | arch/powerpc/kernel/ptrace/ptrace.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/arch/powerpc/kernel/ptrace/ptrace.c b/arch/powerpc/kernel/ptrace/ptrace.c index 7c7093c17c45..c43f77e2ac31 100644 --- a/arch/powerpc/kernel/ptrace/ptrace.c +++ b/arch/powerpc/kernel/ptrace/ptrace.c @@ -260,8 +260,7 @@ long do_syscall_trace_enter(struct pt_regs *regs) { u32 flags; - flags = READ_ONCE(current_thread_info()->flags) & - (_TIF_SYSCALL_EMU | _TIF_SYSCALL_TRACE); + flags = read_thread_flags() & (_TIF_SYSCALL_EMU | _TIF_SYSCALL_TRACE); if (flags) { int rc = tracehook_report_syscall_entry(regs); |