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From 3ad8bb6f424f7ff1d4bbf73237fb1590f0ce1810 Mon Sep 17 00:00:00 2001
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From: Fam Zheng <famz@redhat.com>
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Date: Thu, 18 May 2017 09:21:23 +0200
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Subject: [PATCH 10/18] serial: check if backed by a physical serial port at
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 realize time
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RH-Author: Fam Zheng <famz@redhat.com>
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Message-id: <20170518092131.16571-11-famz@redhat.com>
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Patchwork-id: 75299
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O-Subject: [RHEL-7.4 qemu-kvm PATCH v3 10/18] serial: check if backed by a physical serial port at realize time
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Bugzilla: 1451470
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RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>
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RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
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RH-Acked-by: Eduardo Habkost <ehabkost@redhat.com>
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From: Paolo Bonzini <pbonzini@redhat.com>
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Right now, s->poll_msl may linger at "0" value for an arbitrarily long
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time, until serial_update_msl is called for the first time.  This is
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unnecessary, and will lead to the s->poll_msl field being unnecessarily
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migrated.
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We can call serial_update_msl immediately at realize time (via
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serial_reset) and be done with it.  The memory-mapped UART was already
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doing that, but not the ISA and PCI variants.
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Regarding the delta bits, be consistent with what serial_reset does when
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the serial port is not backed by a physical serial port, and always clear
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them at reset time.
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Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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(cherry picked from commit a30cf8760f4a59797fc060c3c5a13b7749551d0c)
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Signed-off-by: Fam Zheng <famz@redhat.com>
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Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
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---
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 hw/char/serial.c | 5 +++--
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 1 file changed, 3 insertions(+), 2 deletions(-)
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diff --git a/hw/char/serial.c b/hw/char/serial.c
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index 33e06fb..5ef9b95 100644
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--- a/hw/char/serial.c
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+++ b/hw/char/serial.c
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@@ -650,6 +650,9 @@ static void serial_reset(void *opaque)
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     s->thr_ipending = 0;
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     s->last_break_enable = 0;
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     qemu_irq_lower(s->irq);
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+
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+    serial_update_msl(s);
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+    s->msr &= ~UART_MSR_ANY_DELTA;
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 }
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 void serial_init_core(SerialState *s)
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@@ -768,7 +771,5 @@ SerialState *serial_mm_init(MemoryRegion *address_space,
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     memory_region_init_io(&s->io, &serial_mm_ops[end], s,
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                           "serial", 8 << it_shift);
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     memory_region_add_subregion(address_space, base, &s->io);
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-
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-    serial_update_msl(s);
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     return s;
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 }
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-- 
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1.8.3.1
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