qemu/hw/core
Volker Rümelin ff6e1624b3 pckbd: don't update OBF flags if KBD_STAT_OBF is set
Don't update the OBF flags in the status register and the cor-
responding IRQ lines if KBD_STAT_OBF is set. Otherwise this
may change the PS/2 event type. If the guest ISR was already
scheduled, the changed event type will be rather surprising for
the guest.

This fixes a mouse event stream corruption. To reproduce the
problem start a FreeDOS 1.2 guest with -machine pc,accel=kvm
and -display gtk. The KVM in-kernel irqchip has to be enabled.
Now open a text file with edit.exe in the guest and hold down
the cursor right key and at the same time move the mouse around.
You will quickly notice erratic mouse movements and unexpected
mouse clicks.

A trace file shows the mouse event stream corruption. Guest
rip 0xce93 (f000:ce93) is the in al,0x60 instruction in the
seabios mouse ISR, guest rip 0xceca (f000:ceca) is the
in al,0x60 instruction in the seabios keyboard ISR.

qemu-system-x86-5659  [007] ....   280.971116:
 tracing_mark_write: pckbd_kbd_update_irq kbd=0 aux=1
 # gtk queues a mouse event

qemu-system-x86-5665  [000] ....   280.971121:
 kvm_exit: reason EXTERNAL_INTERRUPT rip 0x22da info 0 800000fd
qemu-system-x86-5665  [000] d..1   280.971122:
 kvm_entry: vcpu 0, rip 0x22da
qemu-system-x86-5665  [000] ....   280.971123:
 kvm_exit: reason EXTERNAL_INTERRUPT rip 0x22da info 0 800000fd
qemu-system-x86-5665  [000] d..1   280.971124:
 kvm_entry: vcpu 0, rip 0x22da
qemu-system-x86-5665  [000] ....   280.971126:
 kvm_exit: reason IO_INSTRUCTION rip 0x110c8c info 640008 0
qemu-system-x86-5665  [000] ....   280.971176:
 tracing_mark_write: pckbd_kbd_read_status 0x3d
 # KBD_STAT_OBF and KBD_STAT_MOUSE_OBF set, the mouse ISR will
 # read data from the PS/2 controller.

qemu-system-x86-5665  [000] d..1   280.971180:
 kvm_entry: vcpu 0, rip 0x110c8d
qemu-system-x86-5665  [000] ....   280.971191:
 kvm_exit: reason EXTERNAL_INTERRUPT rip 0x110c8d info 0 800000f6
qemu-system-x86-5665  [000] d..1   280.971191:
 kvm_entry: vcpu 0, rip 0x110c8d
qemu-system-x86-5665  [000] ....   280.971193:
 kvm_exit: reason IO_INSTRUCTION rip 0xce93 info 600048 0
 # the mouse ISR wants to read data from the PS/2 controller

qemu-system-x86-5659  [007] ....   280.971231:
 tracing_mark_write: pckbd_kbd_update_irq kbd=1 aux=0
qemu-system-x86-5659  [007] ....   280.971238:
 tracing_mark_write: pckbd_kbd_update_irq kbd=1 aux=0
 # gtk queues a keyboard event 0xe0 0x4d (key right)

qemu-system-x86-5665  [000] ....   280.971257:
 tracing_mark_write: pckbd_kbd_update_irq kbd=0 aux=1
qemu-system-x86-5665  [000] ....   280.971262:
 tracing_mark_write: pckbd_kbd_update_irq kbd=1 aux=0
 # ps2_read_data() deasserts and reasserts the keyboard IRQ

qemu-system-x86-5665  [000] ....   280.971266:
 tracing_mark_write: pckbd_kbd_read_data 0xe0 kbd
 # -> the mouse ISR receives keyboard data

qemu-system-x86-5665  [000] d..1   280.971268:
 kvm_entry: vcpu 0, rip 0xce95
qemu-system-x86-5665  [000] ....   280.971269:
 kvm_exit: reason IO_INSTRUCTION rip 0xe828 info a00040 0
qemu-system-x86-5665  [000] ....   280.971270:
 kvm_ack_irq: irqchip PIC slave pin 12
qemu-system-x86-5665  [000] d..1   280.971270:
 kvm_entry: vcpu 0, rip 0xe82a
qemu-system-x86-5665  [000] ....   280.971271:
 kvm_exit: reason IO_INSTRUCTION rip 0xe82a info 200040 0
qemu-system-x86-5665  [000] ....   280.971271:
 kvm_ack_irq: irqchip PIC master pin 2
qemu-system-x86-5665  [000] d..1   280.971271:
 kvm_entry: vcpu 0, rip 0xe82c
qemu-system-x86-5665  [000] ....   280.971272:
 kvm_exit: reason PENDING_INTERRUPT rip 0x22da info 0 0
qemu-system-x86-5665  [000] d..1   280.971273:
 kvm_entry: vcpu 0, rip 0x22da
qemu-system-x86-5665  [000] ....   280.971274:
 kvm_exit: reason IO_INSTRUCTION rip 0x110c8c info 640008 0
qemu-system-x86-5665  [000] ....   280.971275:
 tracing_mark_write: pckbd_kbd_read_status 0x1d
qemu-system-x86-5665  [000] d..1   280.971276:
 kvm_entry: vcpu 0, rip 0x110c8d
qemu-system-x86-5665  [000] ....   280.971277:
 kvm_exit: reason IO_INSTRUCTION rip 0xceca info 600048 0
 # the keyboard ISR wants to read data from the PS/2 controller

qemu-system-x86-5665  [000] ....   280.971279:
 tracing_mark_write: pckbd_kbd_update_irq kbd=0 aux=1
qemu-system-x86-5665  [000] ....   280.971282:
 tracing_mark_write: pckbd_kbd_read_data 0x4d kbd
 # the keyboard ISR receives the second byte of the keyboard event

Signed-off-by: Volker Rümelin <vr_qemu@t-online.de>
Message-Id: <20210525181441.27768-5-vr_qemu@t-online.de>

[ kraxel: add missing include ]

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2021-05-26 11:29:56 +02:00
..
bus.c nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
clock-vmstate.c hw/core/clock-vmstate: define a vmstate entry for clock state 2020-04-30 15:35:40 +01:00
clock.c clock: Add ClockPreUpdate callback event type 2021-03-08 17:20:01 +00:00
cpu.c cpu: move debug_check_watchpoint to tcg_ops 2021-02-05 10:24:14 -10:00
fw-path-provider.c Include qemu/module.h where needed, drop it from qemu-common.h 2019-06-12 13:18:33 +02:00
generic-loader.c hw: Do not include hw/sysbus.h if it is not necessary 2021-05-02 17:24:50 +02:00
guest-loader.c hw: Do not include hw/sysbus.h if it is not necessary 2021-05-02 17:24:50 +02:00
guest-loader.h hw/core: implement a guest-loader to support static hypervisor guests 2021-03-10 15:34:11 +00:00
hotplug.c call HotplugHandler->plug() as the last step in device realization 2018-10-19 13:44:12 +02:00
irq.c Use DECLARE_*CHECKER* macros 2020-09-09 09:27:09 -04:00
Kconfig hw/core: Only build guest-loader if libfdt is available 2021-03-17 07:17:46 +00:00
loader-fit.c hw/mips/boston: Fix Lesser GPL version number 2020-11-03 16:51:13 +01:00
loader.c Do not include exec/address-spaces.h if it's not really necessary 2021-05-02 17:24:51 +02:00
machine-hmp-cmds.c machine: remove 'query-cpus' QMP command 2021-03-18 09:22:55 +00:00
machine-qmp-cmds.c Do not include cpu.h if it's not really necessary 2021-05-02 17:24:51 +02:00
machine.c pckbd: don't update OBF flags if KBD_STAT_OBF is set 2021-05-26 11:29:56 +02:00
meson.build hw/core: Only build guest-loader if libfdt is available 2021-03-17 07:17:46 +00:00
nmi.c Include qemu/module.h where needed, drop it from qemu-common.h 2019-06-12 13:18:33 +02:00
null-machine.c Do not include sysemu/sysemu.h if it's not really necessary 2021-05-02 17:24:50 +02:00
numa.c numa: Make all callbacks of ram block notifiers optional 2021-05-13 18:21:13 +01:00
or-irq.c hw/core/or-irq: Fix incorrect assert forbidding num-lines == MAX_OR_LINES 2020-01-30 16:02:01 +00:00
platform-bus.c nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
ptimer.c ptimer: Add new ptimer_set_period_from_clock() function 2021-01-29 15:54:42 +00:00
qdev-clock.c clock: Add ClockEvent parameter to callbacks 2021-03-08 17:20:01 +00:00
qdev-fw.c Include hw/qdev-properties.h less 2019-08-16 13:31:53 +02:00
qdev-prop-internal.h qdev: Make qdev_propinfo_get_uint16() static 2020-12-15 10:02:07 -05:00
qdev-properties-system.c qdev: Rename qdev_get_prop_ptr() to object_field_prop_ptr() 2020-12-18 15:20:18 -05:00
qdev-properties.c qdev: Avoid unnecessary DeviceState* variable at set_prop_arraylen() 2020-12-18 15:20:18 -05:00
qdev.c machine: introduce MachineInitPhase 2020-12-15 12:51:52 -05:00
register.c hw/core/register.c: Don't use '#' flag of printf format 2020-12-17 21:56:43 -08:00
reset.c qemu/queue.h: leave head structs anonymous unless necessary 2019-01-11 15:46:55 +01:00
resettable.c hw/core: deprecate old reset functions and introduce new ones 2020-01-30 16:02:04 +00:00
split-irq.c qdev: set properties with device_class_set_props() 2020-01-24 20:59:15 +01:00
stream.c hw/core/stream: Rename StreamSlave as StreamSink 2020-12-10 12:15:04 -05:00
sysbus.c nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
trace-events hw/core/clock: trace clock values in Hz instead of ns 2020-10-27 11:10:44 +00:00
trace.h trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00
uboot_image.h Support u-boot noload images for arm as used by, NetBSD/evbarm GENERIC kernel. 2019-01-07 15:46:20 +00:00
vm-change-state-handler.c sysemu: Split sysemu/runstate.h off sysemu/sysemu.h 2019-08-16 13:37:36 +02:00
vmstate-if.c vmstate: add qom interface to get id 2020-01-06 18:41:32 +04:00