Blame SOURCES/kvm-ppc-spapr-re-assert-IRQs-during-event-scan-if-there-.patch

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From e4065c7739c8ea3f6f88898295ed899a1059806e Mon Sep 17 00:00:00 2001
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From: Greg Kurz <gkurz@redhat.com>
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Date: Fri, 4 Dec 2020 15:08:00 -0500
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Subject: [PATCH 02/14] ppc/spapr: re-assert IRQs during event-scan if there
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 are pending
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RH-Author: Greg Kurz <gkurz@redhat.com>
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Message-id: <20201204150800.264829-3-gkurz@redhat.com>
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Patchwork-id: 100216
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O-Subject: [RHEL-8.4.0 qemu-kvm PATCH 2/2] ppc/spapr: re-assert IRQs during event-scan if there are pending
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Bugzilla: 1901837
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RH-Acked-by: Danilo de Paula <ddepaula@redhat.com>
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RH-Acked-by: David Gibson <dgibson@redhat.com>
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RH-Acked-by: Laurent Vivier <lvivier@redhat.com>
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From: Laurent Vivier <lvivier@redhat.com>
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If we hotplug a CPU during the first second of the kernel boot,
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the IRQ can be sent to the kernel while the RTAS event handler
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is not installed. The event is queued, but the kernel doesn't
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collect it and ignores the new CPU.
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As the code relies on edge-triggered IRQ, we can re-assert it
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during the event-scan RTAS call if there are still pending
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events (as it is already done in check-exception).
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Signed-off-by: Laurent Vivier <lvivier@redhat.com>
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Message-Id: <20201015210318.117386-1-lvivier@redhat.com>
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Reviewed-by: Greg Kurz <groug@kaod.org>
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Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
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(cherry picked from commit dff669d6a15fb92b063cb5aa691b4bb498727404)
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Signed-off-by: Greg Kurz <gkurz@redhat.com>
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Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
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---
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 hw/ppc/spapr_events.c | 12 ++++++++++++
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 1 file changed, 12 insertions(+)
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diff --git a/hw/ppc/spapr_events.c b/hw/ppc/spapr_events.c
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index e355e000d07..15b92b63adb 100644
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--- a/hw/ppc/spapr_events.c
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+++ b/hw/ppc/spapr_events.c
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@@ -692,10 +692,22 @@ static void event_scan(PowerPCCPU *cpu, SpaprMachineState *spapr,
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                        target_ulong args,
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                        uint32_t nret, target_ulong rets)
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 {
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+    int i;
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     if (nargs != 4 || nret != 1) {
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         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
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         return;
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     }
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+
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+    for (i = 0; i < EVENT_CLASS_MAX; i++) {
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+        if (rtas_event_log_contains(EVENT_CLASS_MASK(i))) {
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+            const SpaprEventSource *source =
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+                spapr_event_sources_get_source(spapr->event_sources, i);
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+
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+            g_assert(source->enabled);
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+            qemu_irq_pulse(spapr_qirq(spapr, source->irq));
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+        }
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+    }
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+
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     rtas_st(rets, 0, RTAS_OUT_NO_ERRORS_FOUND);
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 }
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-- 
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2.27.0
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