| Message ID | 20230822142644.v10.5.Ifadbfd45b22c52edcb499034dd4783d096343260@changeid (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: Add IPI for backtraces / kgdb; try to use NMI for some IPIs | expand |
Quoting Douglas Anderson (2023-08-22 14:27:00) > There's no reason why IPI_CPU_STOP and IPI_CPU_CRASH_STOP can't be > handled as NMI. They are very simple and everything in them is > NMI-safe. Mark them as things to use NMI for if NMI is available. > > Suggested-by: Mark Rutland <mark.rutland@arm.com> > Signed-off-by: Douglas Anderson <dianders@chromium.org> > --- Reviewed-by: Stephen Boyd <swboyd@chromium.org>
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 15b66dc1391b..c51d54019f5f 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -946,6 +946,8 @@ static bool ipi_should_be_nmi(enum ipi_msg_type ipi) return false; switch (ipi) { + case IPI_CPU_STOP: + case IPI_CPU_CRASH_STOP: case IPI_CPU_BACKTRACE: return true; default:
There's no reason why IPI_CPU_STOP and IPI_CPU_CRASH_STOP can't be handled as NMI. They are very simple and everything in them is NMI-safe. Mark them as things to use NMI for if NMI is available. Suggested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> --- I don't actually have any good way to test/validate this patch. It's added to the series at Mark's request. Changes in v10: - ("IPI_CPU_STOP and IPI_CPU_CRASH_STOP should try for NMI") new for v10. arch/arm64/kernel/smp.c | 2 ++ 1 file changed, 2 insertions(+)