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authorJan Kiszka <jan.kiszka@siemens.com>2018-04-05 19:41:47 +0200
committerJason Wang <jasowang@redhat.com>2018-07-20 08:30:48 +0800
commit4712c158c5276fd3c401152f4bb5c3fccf185946 (patch)
tree228699be967677c540afa6b0652d059740aa5c25 /hw/net
parent9f2b67e1ca43c84ed37ebd027e7e77a0f2f8ef65 (diff)
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e1000e: Prevent MSI/MSI-X storms
Only signal MSI/MSI-X events on rising edges. So far we re-triggered the interrupt sources even if the guest did no consumed the pending one, easily causing interrupt storms. Issue was observable with Linux 4.16 e1000e driver when MSI-X was used. Vector 2 was causing interrupt storms after the driver activated the device. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Jason Wang <jasowang@redhat.com>
Diffstat (limited to 'hw/net')
-rw-r--r--hw/net/e1000e_core.c11
-rw-r--r--hw/net/e1000e_core.h2
2 files changed, 13 insertions, 0 deletions
diff --git a/hw/net/e1000e_core.c b/hw/net/e1000e_core.c
index 9504891..2a221c2 100644
--- a/hw/net/e1000e_core.c
+++ b/hw/net/e1000e_core.c
@@ -2023,6 +2023,7 @@ e1000e_msix_notify_one(E1000ECore *core, uint32_t cause, uint32_t int_cfg)
effective_eiac = core->mac[EIAC] & cause;
core->mac[ICR] &= ~effective_eiac;
+ core->msi_causes_pending &= ~effective_eiac;
if (!(core->mac[CTRL_EXT] & E1000_CTRL_EXT_IAME)) {
core->mac[IMS] &= ~effective_eiac;
@@ -2119,6 +2120,13 @@ e1000e_send_msi(E1000ECore *core, bool msix)
{
uint32_t causes = core->mac[ICR] & core->mac[IMS] & ~E1000_ICR_ASSERTED;
+ core->msi_causes_pending &= causes;
+ causes ^= core->msi_causes_pending;
+ if (causes == 0) {
+ return;
+ }
+ core->msi_causes_pending |= causes;
+
if (msix) {
e1000e_msix_notify(core, causes);
} else {
@@ -2156,6 +2164,9 @@ e1000e_update_interrupt_state(E1000ECore *core)
core->mac[ICS] = core->mac[ICR];
interrupts_pending = (core->mac[IMS] & core->mac[ICR]) ? true : false;
+ if (!interrupts_pending) {
+ core->msi_causes_pending = 0;
+ }
trace_e1000e_irq_pending_interrupts(core->mac[ICR] & core->mac[IMS],
core->mac[ICR], core->mac[IMS]);
diff --git a/hw/net/e1000e_core.h b/hw/net/e1000e_core.h
index 7d8ff41..63a1551 100644
--- a/hw/net/e1000e_core.h
+++ b/hw/net/e1000e_core.h
@@ -109,6 +109,8 @@ struct E1000Core {
NICState *owner_nic;
PCIDevice *owner;
void (*owner_start_recv)(PCIDevice *d);
+
+ uint32_t msi_causes_pending;
};
void