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Diffstat (limited to '')
| -rw-r--r-- | debian/patches-rt/0183-hrtimer-Don-t-lose-state-in-cpu_chill.patch | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/debian/patches-rt/0183-hrtimer-Don-t-lose-state-in-cpu_chill.patch b/debian/patches-rt/0183-hrtimer-Don-t-lose-state-in-cpu_chill.patch new file mode 100644 index 000000000..bb9264a1f --- /dev/null +++ b/debian/patches-rt/0183-hrtimer-Don-t-lose-state-in-cpu_chill.patch @@ -0,0 +1,48 @@ +From f5a443f1a8355f1e2aca72d20e931d136b979ac9 Mon Sep 17 00:00:00 2001 +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Tue, 19 Feb 2019 16:59:15 +0100 +Subject: [PATCH 183/347] hrtimer: Don't lose state in cpu_chill() +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.246-rt110.tar.xz + +In cpu_chill() the state is set to TASK_UNINTERRUPTIBLE and a timer is +programmed. On return the state is always TASK_RUNNING which means we +lose the state if it was something other than RUNNING. Also +set_current_state() sets ->task_state_change to within cpu_chill() which +is not expected. + +Save the task state on entry and restore it on return. Simply set the +state in order to avoid updating ->task_state_change. + +Cc: stable-rt@vger.kernel.org +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + kernel/time/hrtimer.c | 5 ++++- + 1 file changed, 4 insertions(+), 1 deletion(-) + +diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c +index 0b94f54453ef..96e505abf939 100644 +--- a/kernel/time/hrtimer.c ++++ b/kernel/time/hrtimer.c +@@ -1969,15 +1969,18 @@ void cpu_chill(void) + { + ktime_t chill_time; + unsigned int freeze_flag = current->flags & PF_NOFREEZE; ++ long saved_state; + ++ saved_state = current->state; + chill_time = ktime_set(0, NSEC_PER_MSEC); +- set_current_state(TASK_UNINTERRUPTIBLE); ++ __set_current_state_no_track(TASK_UNINTERRUPTIBLE); + current->flags |= PF_NOFREEZE; + sleeping_lock_inc(); + schedule_hrtimeout(&chill_time, HRTIMER_MODE_REL_HARD); + sleeping_lock_dec(); + if (!freeze_flag) + current->flags &= ~PF_NOFREEZE; ++ __set_current_state_no_track(saved_state); + } + EXPORT_SYMBOL(cpu_chill); + #endif +-- +2.36.1 + |