From c57c0ad4a3ddd5cc697b1956c00d8c7c2cb7dc12 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 25 Apr 2018 16:28:27 +0200 Subject: ACPICA: Convert acpi_gbl_hardware lock back to an acpi_raw_spinlock MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We hit the following bug with -RT: |BUG: scheduling while atomic: swapper/7/0/0x00000002 |Pid: 0, comm: swapper/7 Not tainted 3.6.11-rt28.19.el6rt.x86_64.debug #1 |Call Trace: | rt_spin_lock+0x16/0x40 | __schedule_bug+0x67/0x90 | __schedule+0x793/0x7a0 | acpi_os_acquire_lock+0x1f/0x23 | acpi_write_bit_register+0x33/0xb0 | rt_spin_lock_slowlock+0xe5/0x2f0 | acpi_idle_enter_bm+0x8a/0x28e … As the acpi code disables interrupts in acpi_idle_enter_bm, and calls code that grabs the acpi lock, it causes issues as the lock is currently in RT a sleeping lock. The lock was converted from a raw to a sleeping lock due to some previous issues, and tests that showed it didn't seem to matter. Unfortunately, it did matter for one of our boxes. This patch converts the lock back to a raw lock. I've run this code on a few of my own machines, one being my laptop that uses the acpi quite extensively. I've been able to suspend and resume without issues. [ tglx: Made the change exclusive for acpi_gbl_hardware_lock ] Signed-off-by: Steven Rostedt Link: http://lkml.kernel.org/r/1360765565.23152.5.camel@gandalf.local.home Signed-off-by: Thomas Gleixner [bigeasy: shorten the backtrace, use the type acpi_raw_spinlock incl. accessor] Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpica/utmutex.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/acpi/acpica/utmutex.c') diff --git a/drivers/acpi/acpica/utmutex.c b/drivers/acpi/acpica/utmutex.c index d2d93e388f40..2e465e6a0ab6 100644 --- a/drivers/acpi/acpica/utmutex.c +++ b/drivers/acpi/acpica/utmutex.c @@ -52,7 +52,7 @@ acpi_status acpi_ut_mutex_initialize(void) return_ACPI_STATUS (status); } - status = acpi_os_create_lock (&acpi_gbl_hardware_lock); + status = acpi_os_create_raw_lock(&acpi_gbl_hardware_lock); if (ACPI_FAILURE (status)) { return_ACPI_STATUS (status); } @@ -109,7 +109,7 @@ void acpi_ut_mutex_terminate(void) /* Delete the spinlocks */ acpi_os_delete_lock(acpi_gbl_gpe_lock); - acpi_os_delete_lock(acpi_gbl_hardware_lock); + acpi_os_delete_raw_lock(acpi_gbl_hardware_lock); acpi_os_delete_lock(acpi_gbl_reference_count_lock); /* Delete the reader/writer lock */ -- cgit v1.2.3