Commit Graph

12 Commits

Author SHA1 Message Date
Peter Maydell
823e1b3818 arm: Allow system registers for KVM guests to be changed by QEMU code
At the moment the Arm implementations of kvm_arch_{get,put}_registers()
don't support having QEMU change the values of system registers
(aka coprocessor registers for AArch32). This is because although
kvm_arch_get_registers() calls write_list_to_cpustate() to
update the CPU state struct fields (so QEMU code can read the
values in the usual way), kvm_arch_put_registers() does not
call write_cpustate_to_list(), meaning that any changes to
the CPU state struct fields will not be passed back to KVM.

The rationale for this design is documented in a comment in the
AArch32 kvm_arch_put_registers() -- writing the values in the
cpregs list into the CPU state struct is "lossy" because the
write of a register might not succeed, and so if we blindly
copy the CPU state values back again we will incorrectly
change register values for the guest. The assumption was that
no QEMU code would need to write to the registers.

However, when we implemented debug support for KVM guests, we
broke that assumption: the code to handle "set the guest up
to take a breakpoint exception" does so by updating various
guest registers including ESR_EL1.

Support this by making kvm_arch_put_registers() synchronize
CPU state back into the list. We sync only those registers
where the initial write succeeds, which should be sufficient.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Dongjiu Geng <gengdongjiu@huawei.com>
2019-02-15 09:56:39 +00:00
Richard Henderson
3c3efcf7da target/arm: Fill in ARMISARegisters for kvm32
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20181113180154.17903-5-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-11-19 15:29:08 +00:00
Richard Henderson
b653c55fa7 target/arm: Introduce read_sys_reg32 for kvm32
Assert that the value to be written is the correct size.
No change in functionality here, just mirroring the same
function from kvm64.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20181113180154.17903-4-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-11-19 15:29:07 +00:00
Peter Maydell
593cfa2b63 target/arm: Hyp mode R14 is shared with User and System
Hyp mode is an exception to the general rule that each AArch32
mode has its own r13, r14 and SPSR -- it has a banked r13 and
SPSR but shares its r14 with User and System mode. We were
incorrectly implementing it as banked, which meant that on
entry to Hyp mode r14 was 0 rather than the USR/SYS r14.

We provide a new function r14_bank_number() which is like
the existing bank_number() but provides the index into
env->banked_r14[]; bank_number() provides the index to use
for env->banked_r13[] and env->banked_cpsr[].

All the points in the code that were using bank_number()
to index into env->banked_r14[] are updated for consintency:
 * switch_mode() -- this is the only place where we fix
   an actual bug
 * aarch64_sync_32_to_64() and aarch64_sync_64_to_32():
   no behavioural change as we already special-cased Hyp R14
 * kvm32.c: no behavioural change since the guest can't ever
   be in Hyp mode, but conceptually the right thing to do
 * msr_banked()/mrs_banked(): we can never get to the case
   that accesses banked_r14[] with tgtmode == ARM_CPU_MODE_HYP,
   so no behavioural change

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20181109173553.22341-2-peter.maydell@linaro.org
2018-11-13 10:47:59 +00:00
Dongjiu Geng
202ccb6bab target/arm: Add support for VCPU event states
This patch extends the qemu-kvm state sync logic with support for
KVM_GET/SET_VCPU_EVENTS, giving access to yet missing SError exception.
And also it can support the exception state migration.

The SError exception states include SError pending state and ESR value,
the kvm_put/get_vcpu_events() will be called when set or get system
registers. When do migration, if source machine has SError pending,
QEMU will do this migration regardless whether the target machine supports
to specify guest ESR value, because if target machine does not support that,
it can also inject the SError with zero ESR value.

Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1538067351-23931-3-git-send-email-gengdongjiu@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-10-24 07:50:16 +01:00
Aaron Lindsay
a6070648aa target/arm: Remove redundant DIV detection for KVM
KVM implies V7VE, which implies ARM_DIV and THUMB_DIV. The conditional
detection here is therefore unnecessary. Because V7VE is already
unconditionally specified for all KVM hosts, ARM_DIV and THUMB_DIV are
already indirectly specified and do not need to be included here at all.

Signed-off-by: Aaron Lindsay <alindsay@codeaurora.org>
Message-id: 1529699547-17044-6-git-send-email-alindsay@codeaurora.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-29 15:11:18 +01:00
Aaron Lindsay
5110e6836b target/arm: Add ARM_FEATURE_V7VE for v7 Virtualization Extensions
Signed-off-by: Aaron Lindsay <alindsay@codeaurora.org>
Message-id: 1529699547-17044-5-git-send-email-alindsay@codeaurora.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-29 15:11:17 +01:00
Peter Maydell
c4487d76d5 target/arm: Query host CPU features on-demand at instance init
Currently we query the host CPU features in the class init function
for the TYPE_ARM_HOST_CPU class, so that we can later copy them
from the class object into the instance object in the object
instance init function. This is awkward for implementing "-cpu max",
which should work like "-cpu host" for KVM but like "cpu with all
implemented features" for TCG.

Move the place where we store the information about the host CPU from
a class object to static variables in kvm.c, and then in the instance
init function call a new kvm_arm_set_cpu_features_from_host()
function which will query the host kernel if necessary and then
fill in the CPU instance fields.

This allows us to drop the special class struct and class init
function for TYPE_ARM_HOST_CPU entirely.

We can't delay the probe until realize, because the ARM
instance_post_init hook needs to look at the feature bits we
set, so we need to do it in the initfn. This is safe because
the probing doesn't affect the actual VM state (it creates a
separate scratch VM to do its testing), but the probe might fail.
Because we can't report errors in retrieving the host features
in the initfn, we check this belatedly in the realize function
(the intervening code will be able to cope with the relevant
fields in the CPU structure being zero).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20180308130626.12393-2-peter.maydell@linaro.org
2018-03-09 17:09:44 +00:00
Richard Henderson
9a2b5256ea target/arm: Add aa{32, 64}_vfp_{dreg, qreg} helpers
Helpers that return a pointer into env->vfp.regs so that we isolate
the logic of how to index the regs array for different cpu modes.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180119045438.28582-7-richard.henderson@linaro.org
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-01-25 11:45:29 +00:00
Andrew Jones
b2bfe9f7f1 target/arm/kvm: pmu: improve error handling
If a KVM PMU init or set-irq attr call fails we just silently stop
the PMU DT node generation. The only way they could fail, though,
is if the attr's respective KVM has-attr call fails. But that should
never happen if KVM advertises the PMU capability, because both
attrs have been available since the capability was introduced. Let's
just abort if this should-never-happen stuff does happen, because,
if it does, then something is obviously horribly wrong.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Message-id: 1500471597-2517-5-git-send-email-drjones@redhat.com
[PMM: change kvm32.c kvm_arm_pmu_init() to the new API too]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-09-04 15:21:54 +01:00
Andrew Jones
3f07cb2aab target/arm/kvm: pmu: split init and set-irq stages
When adding a PMU with a userspace irqchip we skip the set-irq
stage of device creation. Split the 'create' function into two
functions 'init' and 'set-irq' so they may be called separately.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Message-id: 1500471597-2517-3-git-send-email-drjones@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-09-04 15:21:54 +01:00
Thomas Huth
fcf5ef2ab5 Move target-* CPU file into a target/ folder
We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.

Acked-by: Laurent Vivier <laurent@vivier.eu> [m68k part]
Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> [tricore part]
Acked-by: Michael Walle <michael@walle.cc> [lm32 part]
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x part]
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [s390x part]
Acked-by: Eduardo Habkost <ehabkost@redhat.com> [i386 part]
Acked-by: Artyom Tarasenko <atar4qemu@gmail.com> [sparc part]
Acked-by: Richard Henderson <rth@twiddle.net> [alpha part]
Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa part]
Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [ppc part]
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> [cris&microblaze part]
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2016-12-20 21:52:12 +01:00