From: Mykola Kvach <mykola_kv...@epam.com>
If we call disable_nonboot_cpus on ARM64 with system_state set
to SYS_STATE_suspend, the following assertion will be triggered:
```
(XEN) [ 25.582712] Disabling non-boot CPUs ...
(XEN) [ 25.587032] Assertion '!in_irq() && (local_irq_is_enabled() ||
num_online_cpus() <= 1)' failed at common/xmalloc_tlsf.c:714
[...]
(XEN) [ 25.975069] Xen call trace:
(XEN) [ 25.978353] [<00000a000022e098>] xfree+0x130/0x1a4 (PC)
(XEN) [ 25.984314] [<00000a000022e08c>] xfree+0x124/0x1a4 (LR)
(XEN) [ 25.990276] [<00000a00002747d4>] release_irq+0xe4/0xe8
(XEN) [ 25.996152] [<00000a0000278588>] time.c#cpu_time_callback+0x44/0x60
(XEN) [ 26.003150] [<00000a000021d678>] notifier_call_chain+0x7c/0xa0
(XEN) [ 26.009717] [<00000a00002018e0>]
cpu.c#cpu_notifier_call_chain+0x24/0x48
(XEN) [ 26.017148] [<00000a000020192c>] cpu.c#_take_cpu_down+0x28/0x34
(XEN) [ 26.023801] [<00000a0000201944>] cpu.c#take_cpu_down+0xc/0x18
(XEN) [ 26.030281] [<00000a0000225c5c>]
stop_machine.c#stopmachine_action+0xbc/0xe4
(XEN) [ 26.038057] [<00000a00002264bc>]
tasklet.c#do_tasklet_work+0xb8/0x100
(XEN) [ 26.045229] [<00000a00002268a4>] do_tasklet+0x68/0xb0
(XEN) [ 26.051018] [<00000a000026e120>] domain.c#idle_loop+0x7c/0x194
(XEN) [ 26.057585] [<00000a0000277e30>] start_secondary+0x21c/0x220
(XEN) [ 26.063978] [<00000a0000361258>] 00000a0000361258
```
This happens because before invoking take_cpu_down via the stop_machine_run
function on the target CPU, stop_machine_run requests
the STOPMACHINE_DISABLE_IRQ state on that CPU. Releasing memory in
the release_irq function then triggers the assertion:
/*
* Heap allocations may need TLB flushes which may require IRQs to be
* enabled (except when only 1 PCPU is online).
*/
This patch adds system state checks to guard calls to request_irq
and release_irq. These calls are now skipped when system_state is
SYS_STATE_{resume,suspend}, preventing unsafe operations during
suspend/resume handling.
Signed-off-by: Mykola Kvach <mykola_kv...@epam.com>
---
Changes in V6:
- skipping of IRQ release during system suspend is now handled
inside release_irq().
Changes in V4:
- removed the prior tasklet-based workaround in favor of a more
straightforward and safer solution
- reworked the approach by adding explicit system state checks around
request_irq and release_irq calls, skips these calls during suspend
and resume states to avoid unsafe memory operations when IRQs are
disabled
---
xen/arch/arm/gic.c | 3 +++
xen/arch/arm/irq.c | 3 +++
xen/arch/arm/tee/ffa_notif.c | 2 +-
xen/arch/arm/time.c | 11 +++++++----
4 files changed, 14 insertions(+), 5 deletions(-)
diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
index a018bd7715..c64481faa7 100644
--- a/xen/arch/arm/gic.c
+++ b/xen/arch/arm/gic.c
@@ -388,6 +388,9 @@ void gic_dump_info(struct vcpu *v)
void init_maintenance_interrupt(void)
{
+ if ( system_state == SYS_STATE_resume )
+ return;
+
request_irq(gic_hw_ops->info->maintenance_irq, 0, maintenance_interrupt,
"irq-maintenance", NULL);
}
diff --git a/xen/arch/arm/irq.c b/xen/arch/arm/irq.c
index 02ca82c089..361496a6d0 100644
--- a/xen/arch/arm/irq.c
+++ b/xen/arch/arm/irq.c
@@ -300,6 +300,9 @@ void release_irq(unsigned int irq, const void *dev_id)
unsigned long flags;
struct irqaction *action, **action_ptr;
+ if ( system_state == SYS_STATE_suspend )
+ return;
+
desc = irq_to_desc(irq);
spin_lock_irqsave(&desc->lock,flags);
diff --git a/xen/arch/arm/tee/ffa_notif.c b/xen/arch/arm/tee/ffa_notif.c
index 86bef6b3b2..4835e25619 100644
--- a/xen/arch/arm/tee/ffa_notif.c
+++ b/xen/arch/arm/tee/ffa_notif.c
@@ -363,7 +363,7 @@ void ffa_notif_init_interrupt(void)
{
int ret;
- if ( fw_notif_enabled && notif_sri_irq < NR_GIC_SGI )
+ if ( fw_notif_enabled && notif_sri_irq < NR_GIC_SGI && system_state !=
SYS_STATE_resume )
{
/*
* An error here is unlikely since the primary CPU has already
diff --git a/xen/arch/arm/time.c b/xen/arch/arm/time.c
index ad984fdfdd..8267fa5191 100644
--- a/xen/arch/arm/time.c
+++ b/xen/arch/arm/time.c
@@ -320,10 +320,13 @@ void init_timer_interrupt(void)
WRITE_SYSREG(CNTHCTL_EL2_EL1PCTEN, CNTHCTL_EL2);
disable_physical_timers();
- request_irq(timer_irq[TIMER_HYP_PPI], 0, htimer_interrupt,
- "hyptimer", NULL);
- request_irq(timer_irq[TIMER_VIRT_PPI], 0, vtimer_interrupt,
- "virtimer", NULL);
+ if ( system_state != SYS_STATE_resume )
+ {
+ request_irq(timer_irq[TIMER_HYP_PPI], 0, htimer_interrupt,
+ "hyptimer", NULL);
+ request_irq(timer_irq[TIMER_VIRT_PPI], 0, vtimer_interrupt,
+ "virtimer", NULL);
+ }
check_timer_irq_cfg(timer_irq[TIMER_HYP_PPI], "hypervisor");
check_timer_irq_cfg(timer_irq[TIMER_VIRT_PPI], "virtual");
--
2.48.1
