qemu/target/i386
Mark Cave-Ayland 7653b44534 target/i386/translate.c: always write 32-bits for SGDT and SIDT
The various Intel CPU manuals claim that SGDT and SIDT can write either 24-bits
or 32-bits depending upon the operand size, but this is incorrect. Not only do
the Intel CPU manuals give contradictory information between processor
revisions, but this information doesn't even match real-life behaviour.

In fact, tests on real hardware show that the CPU always writes 32-bits for SGDT
and SIDT, and this behaviour is required for at least OS/2 Warp and WFW 3.11 with
Win32s to function correctly. Remove the masking applied due to the operand size
for SGDT and SIDT so that the TCG behaviour matches the behaviour on real
hardware.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2198

--
MCA: Whilst I don't have a copy of OS/2 Warp handy, I've confirmed that this
patch fixes the issue in WFW 3.11 with Win32s. For more technical information I
highly recommend the excellent write-up at
https://www.os2museum.com/wp/sgdtsidt-fiction-and-reality/.
Message-ID: <20240419195147.434894-1-mark.cave-ayland@ilande.co.uk>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-23 17:35:26 +02:00
..
hvf accel/hvf: Un-inline hvf_arch_supports_guest_debug() 2024-04-02 14:55:32 +02:00
kvm target/i386: SEV: use KVM_SEV_INIT2 if possible 2024-04-23 17:35:25 +02:00
nvmm bulk: Call in place single use cpu_env() 2024-03-12 11:46:16 +01:00
tcg target/i386/translate.c: always write 32-bits for SGDT and SIDT 2024-04-23 17:35:26 +02:00
whpx bulk: Call in place single use cpu_env() 2024-03-12 11:46:16 +01:00
arch_dump.c dump: Replace opaque DumpState pointer with a typed one 2022-10-06 19:30:43 +04:00
arch_memory_mapping.c memory: follow Error API guidelines 2023-10-19 23:13:27 +02:00
confidential-guest.c target/i386: introduce x86-confidential-guest 2024-04-23 17:35:25 +02:00
confidential-guest.h target/i386: Implement mc->kvm_type() to get VM type 2024-04-23 17:35:25 +02:00
cpu-dump.c target/i386: Remove x86_cpu_dump_local_apic_state() dead stub 2023-02-27 22:29:01 +01:00
cpu-internal.h i386: split off sysemu part of cpu.c 2021-05-10 15:41:52 -04:00
cpu-param.h target/i386: Remove NB_MMU_MODES define 2023-03-13 06:44:37 -07:00
cpu-qom.h target: Move ArchCPUClass definition to 'cpu.h' 2023-11-07 13:08:48 +01:00
cpu-sysemu.c target: Improve error reporting for CpuModelInfo member @props 2024-03-12 14:03:00 +01:00
cpu.c target/i386/cpu: Merge the warning and error messages for AMD HT check 2024-04-23 17:35:26 +02:00
cpu.h target/i386: add guest-phys-bits cpu property 2024-04-18 11:17:28 +02:00
gdbstub.c gdbstub: move register helpers into standalone include 2023-03-07 20:44:08 +00:00
helper.c target/i386: Revert monitor_puts() in do_inject_x86_mce() 2024-03-20 09:47:00 +01:00
helper.h target/i386: implement SYSCALL/SYSRET in 32-bit emulators 2023-06-26 10:23:56 +02:00
host-cpu.c target/i386/host-cpu: Consolidate the use of warn_report_once() 2024-04-23 17:35:26 +02:00
host-cpu.h accel-cpu: make cpu_realizefn return a bool 2021-05-10 15:41:50 -04:00
Kconfig meson: Introduce target-specific Kconfig 2021-07-09 18:21:34 +02:00
machine.c target/i386: Constify VMState in machine.c 2023-12-29 11:17:30 +11:00
meson.build target/i386: introduce x86-confidential-guest 2024-04-23 17:35:25 +02:00
monitor.c target/i386/monitor: Remove unused 'hw/i386/pc.h' header 2024-02-20 20:34:21 +03:00
ops_sse.h target/i386: implement SHA instructions 2023-10-25 17:35:07 +02:00
sev-sysemu-stub.c error: Drop superfluous #include "qapi/qmp/qerror.h" 2023-02-23 13:56:14 +01:00
sev.c hw/i386/sev: Use legacy SEV VM types for older machine types 2024-04-23 17:35:25 +02:00
sev.h i386/sev: Switch to use confidential_guest_kvm_init() 2024-04-23 17:35:25 +02:00
svm.h target/i386: check intercept for XSETBV 2023-10-17 15:20:53 +02:00
trace-events * Update the references to some doc files (use *.rst instead of *.txt) 2021-06-02 17:08:11 +01:00
trace.h trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00
xsave_helper.c x86: add support for KVM_CAP_XSAVE2 and AMX state migration 2022-03-15 11:50:50 +01:00