diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-06-25 10:19:01 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-06-25 10:19:01 -0700 |
| commit | b960e0147451915b5d4cd208b7abd3b07ceaf1a2 (patch) | |
| tree | 13a1541e033fb5ca3989f1cff330759290236b0a /drivers | |
| parent | 616a99dd146a799d0cac43f884a3a46571bd2796 (diff) | |
| parent | 3de218ff39b9e3f0d453fe3154f12a174de44b25 (diff) | |
Merge tag 'for-linus-5.13b-rc8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fix from Juergen Gross:
"A fix for a regression introduced in 5.12: when migrating an irq
related to a Xen user event to another cpu, a race might result
in a WARN() triggering"
* tag 'for-linus-5.13b-rc8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/events: reset active flag for lateeoi events later
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/xen/events/events_base.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index 7bbfd58958bc..d7e361fb0548 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -642,6 +642,9 @@ static void xen_irq_lateeoi_locked(struct irq_info *info, bool spurious) } info->eoi_time = 0; + + /* is_active hasn't been reset yet, do it now. */ + smp_store_release(&info->is_active, 0); do_unmask(info, EVT_MASK_REASON_EOI_PENDING); } @@ -811,6 +814,7 @@ static void xen_evtchn_close(evtchn_port_t port) BUG(); } +/* Not called for lateeoi events. */ static void event_handler_exit(struct irq_info *info) { smp_store_release(&info->is_active, 0); @@ -1883,7 +1887,12 @@ static void lateeoi_ack_dynirq(struct irq_data *data) if (VALID_EVTCHN(evtchn)) { do_mask(info, EVT_MASK_REASON_EOI_PENDING); - event_handler_exit(info); + /* + * Don't call event_handler_exit(). + * Need to keep is_active non-zero in order to ignore re-raised + * events after cpu affinity changes while a lateeoi is pending. + */ + clear_evtchn(evtchn); } } |