nagai/kernel
3
0
Fork 0
forked from mirrors/linux
Code Pull requests Activity

ACPI: processor_idle: use raw_safe_halt() in acpi_idle_play_dead()

Browse source 
Xen HVM guests were observed taking triple-faults when attempting to
online a previously offlined vCPU.

Investigation showed that the fault was coming from a failing call
to lockdep_assert_irqs_disabled(), in load_current_idt() which was
too early in the CPU bringup to actually catch the exception and
report the failure cleanly.

This was a false positive, caused by acpi_idle_play_dead() setting
the per-cpu hardirqs_enabled flag by calling safe_halt(). Switch it
to use raw_safe_halt() instead, which doesn't do so.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: 6.6+ <stable@vger.kernel.org> # 6.6+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
David Woodhouse 2023-10-27 19:36:51 +01:00 committed by Rafael J. Wysocki
parent 98b1cc82c4
commit 9bb69ba4c1
1 changed files with 1 additions and 1 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

2
drivers/acpi/processor_idle.c
View file

@ -592,7 +592,7 @@ static int acpi_idle_play_dead(struct cpuidle_device *dev, int index)
while (1) { while (1) {
if (cx->entry_method == ACPI_CSTATE_HALT) if (cx->entry_method == ACPI_CSTATE_HALT)
safe_halt(); raw_safe_halt();
else if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) { else if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) {
io_idle(cx->address); io_idle(cx->address);
} else } else