From cdeaed27782835a875df7365d56d69dbe7250481 Mon Sep 17 00:00:00 2001 From: Babu Moger Date: Wed, 3 Mar 2021 09:45:30 -0600 Subject: [PATCH 1/2] i386: Add missing cpu feature bits in EPYC-Rome model Found the following cpu feature bits missing from EPYC-Rome model. ibrs : Indirect Branch Restricted Speculation ssbd : Speculative Store Bypass Disable These new features will be added in EPYC-Rome-v2. The -cpu help output after the change. x86 EPYC-Rome (alias configured by machine type) x86 EPYC-Rome-v1 AMD EPYC-Rome Processor x86 EPYC-Rome-v2 AMD EPYC-Rome Processor Reported-by: Pankaj Gupta Signed-off-by: Babu Moger Signed-off-by: Pankaj Gupta Signed-off-by: Eduardo Habkost Reviewed-by: David Edmondson Message-Id: <161478622280.16275.6399866734509127420.stgit@bmoger-ubuntu> Signed-off-by: Eduardo Habkost --- target/i386/cpu.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/target/i386/cpu.c b/target/i386/cpu.c index 6b3e9467f1..ad99cad0e7 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -4179,6 +4179,18 @@ static X86CPUDefinition builtin_x86_defs[] = { .xlevel = 0x8000001E, .model_id = "AMD EPYC-Rome Processor", .cache_info = &epyc_rome_cache_info, + .versions = (X86CPUVersionDefinition[]) { + { .version = 1 }, + { + .version = 2, + .props = (PropValue[]) { + { "ibrs", "on" }, + { "amd-ssbd", "on" }, + { /* end of list */ } + } + }, + { /* end of list */ } + } }, { .name = "EPYC-Milan", From 0b47ec4b95ad1952e55e639711d442f8ec6e1345 Mon Sep 17 00:00:00 2001 From: Greg Kurz Date: Fri, 9 Apr 2021 18:03:39 +0200 Subject: [PATCH 2/2] cpu/core: Fix "help" of CPU core device types Calling qdev_get_machine() from a QOM instance_init function is fragile because we can't be sure the machine object actually exists. And this happens to break when passing ",help" on the command line to get the list of properties for a CPU core device types : $ ./qemu-system-ppc64 -device power8_v2.0-spapr-cpu-core,help qemu-system-ppc64: ../../hw/core/machine.c:1290: qdev_get_machine: Assertion `machine != NULL' failed. Aborted (core dumped) This used to work before QEMU 5.0, but commit 3df261b6676b unwillingly introduced a subtle regression : the above command line needs to create an instance but the instance_init function of the base class calls qdev_get_machine() before qemu_create_machine() has been called, which is a programming bug. Use current_machine instead. It is okay to skip the setting of nr_thread in this case since only its type is displayed. Fixes: 3df261b6676b ("softmmu/vl.c: Handle '-cpu help' and '-device help' before 'no default machine'") Reported-by: Thomas Huth Signed-off-by: Greg Kurz Cc: peter.maydell@linaro.org Message-Id: <20210409160339.500167-3-groug@kaod.org> Signed-off-by: Eduardo Habkost --- hw/cpu/core.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/hw/cpu/core.c b/hw/cpu/core.c index 92d3b2fbad..9876075155 100644 --- a/hw/cpu/core.c +++ b/hw/cpu/core.c @@ -66,10 +66,16 @@ static void core_prop_set_nr_threads(Object *obj, Visitor *v, const char *name, static void cpu_core_instance_init(Object *obj) { - MachineState *ms = MACHINE(qdev_get_machine()); CPUCore *core = CPU_CORE(obj); - core->nr_threads = ms->smp.threads; + /* + * Only '-device something-cpu-core,help' can get us there before + * the machine has been created. We don't care to set nr_threads + * in this case since it isn't used afterwards. + */ + if (current_machine) { + core->nr_threads = current_machine->smp.threads; + } } static void cpu_core_class_init(ObjectClass *oc, void *data)