[PULL 13/13] apic: disable reentrancy detection for apic-msi

Thomas Huth posted 13 patches 2 years, 9 months ago
Maintainers: Laurent Vivier <laurent@vivier.eu>, Thomas Huth <thuth@redhat.com>, Halil Pasic <pasic@linux.ibm.com>, Christian Borntraeger <borntraeger@linux.ibm.com>, "Alex Bennée" <alex.bennee@linaro.org>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, Stefano Stabellini <sstabellini@kernel.org>, Anthony Perard <anthony.perard@citrix.com>, Paul Durrant <paul@xen.org>, Stefan Hajnoczi <stefanha@redhat.com>, Kevin Wolf <kwolf@redhat.com>, Hanna Reitz <hreitz@redhat.com>, Amit Shah <amit@kernel.org>, "Michael S. Tsirkin" <mst@redhat.com>, "Marc-André Lureau" <marcandre.lureau@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, Gerd Hoffmann <kraxel@redhat.com>, John Snow <jsnow@redhat.com>, Peter Maydell <peter.maydell@linaro.org>, Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>, Jason Wang <jasowang@redhat.com>, Keith Busch <kbusch@kernel.org>, Klaus Jensen <its@irrelevant.dk>, "Hervé Poussineau" <hpoussin@reactos.org>, Yuval Shaia <yuval.shaia.ml@gmail.com>, Marcel Apfelbaum <marcel.apfelbaum@gmail.com>, Fam Zheng <fam@euphon.net>, Dmitry Fleytman <dmitry.fleytman@gmail.com>, David Hildenbrand <david@redhat.com>, "Gonglei (Arei)" <arei.gonglei@huawei.com>, Peter Xu <peterx@redhat.com>, "Daniel P. Berrangé" <berrange@redhat.com>, Eduardo Habkost <eduardo@habkost.net>, Richard Henderson <richard.henderson@linaro.org>, Ilya Leoshkevich <iii@linux.ibm.com>
[PULL 13/13] apic: disable reentrancy detection for apic-msi
Posted by Thomas Huth 2 years, 9 months ago
From: Alexander Bulekov <alxndr@bu.edu>

As the code is designed for re-entrant calls to apic-msi, mark apic-msi
as reentrancy-safe.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20230427211013.2994127-9-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 hw/intc/apic.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/hw/intc/apic.c b/hw/intc/apic.c
index 20b5a94073..ac3d47d231 100644
--- a/hw/intc/apic.c
+++ b/hw/intc/apic.c
@@ -885,6 +885,13 @@ static void apic_realize(DeviceState *dev, Error **errp)
     memory_region_init_io(&s->io_memory, OBJECT(s), &apic_io_ops, s, "apic-msi",
                           APIC_SPACE_SIZE);
 
+    /*
+     * apic-msi's apic_mem_write can call into ioapic_eoi_broadcast, which can
+     * write back to apic-msi. As such mark the apic-msi region re-entrancy
+     * safe.
+     */
+    s->io_memory.disable_reentrancy_guard = true;
+
     s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, apic_timer, s);
     local_apics[s->id] = s;
 
-- 
2.31.1