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hpet: guard IRQ handling with BQL

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Commit [1] made qemu fail with abort:
  xen_evtchn_set_gsi: Assertion `bql_locked()' failed.
when running ./tests/functional/x86_64/test_kvm_xen.py tests.

To fix it make sure that BQL is held when manipulating IRQs.

Fixes: 7defb58baf (hpet: switch to fine-grained device locking)
Reported-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Link: https://lore.kernel.org/r/20250910142506.86274-1-imammedo@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Igor Mammedov 2025-09-10 16:25:06 +02:00 • committed by Paolo Bonzini
parent 7c83e50156
commit d99041a203
1 changed files with 8 additions and 0 deletions
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8
hw/timer/hpet.c
View file

@ -40,6 +40,7 @@
#include "qom/object.h"
#include "qemu/lockable.h"
#include "qemu/seqlock.h"
#include "qemu/main-loop.h"
#include "trace.h"
struct hpet_fw_config hpet_fw_cfg = {.count = UINT8_MAX};
@ -222,12 +223,15 @@ static void update_irq(struct HPETTimer *timer, int set)
timer->fsb & 0xffffffff, MEMTXATTRS_UNSPECIFIED,
NULL);
} else if (timer->config & HPET_TN_TYPE_LEVEL) {
BQL_LOCK_GUARD();
qemu_irq_raise(s->irqs[route]);
} else {
BQL_LOCK_GUARD();
qemu_irq_pulse(s->irqs[route]);
}
} else {
if (!timer_fsb_route(timer)) {
BQL_LOCK_GUARD();
qemu_irq_lower(s->irqs[route]);
}
}
@ -534,10 +538,12 @@ static void hpet_ram_write(void *opaque, hwaddr addr,
/* i8254 and RTC output pins are disabled
* when HPET is in legacy mode */
if (activating_bit(old_val, new_val, HPET_CFG_LEGACY)) {
BQL_LOCK_GUARD();
qemu_set_irq(s->pit_enabled, 0);
qemu_irq_lower(s->irqs[0]);
qemu_irq_lower(s->irqs[RTC_ISA_IRQ]);
} else if (deactivating_bit(old_val, new_val, HPET_CFG_LEGACY)) {
BQL_LOCK_GUARD();
qemu_irq_lower(s->irqs[0]);
qemu_set_irq(s->pit_enabled, 1);
qemu_set_irq(s->irqs[RTC_ISA_IRQ], s->rtc_irq_level);
@ -683,11 +689,13 @@ static void hpet_handle_legacy_irq(void *opaque, int n, int level)
if (n == HPET_LEGACY_PIT_INT) {
if (!hpet_in_legacy_mode(s)) {
BQL_LOCK_GUARD();
qemu_set_irq(s->irqs[0], level);
}
} else {
s->rtc_irq_level = level;
if (!hpet_in_legacy_mode(s)) {
BQL_LOCK_GUARD();
qemu_set_irq(s->irqs[RTC_ISA_IRQ], level);
}
}