Code generation was rewritten; it reuses the same trick to use the
CC_OP_SAR values for cc_op, but it tries to use CC_OP_ADCX or CC_OP_ADCOX
instead of CC_OP_EFLAGS. This is a tiny bit more efficient in the
common case where only CF is checked in the resulting flags.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
32-bit TSTEQ and TSTNE is subject to the same constraints as
for 64-bit, but setcond_i32 and negsetcond_i32 were incorrectly
using TCG_CT_CONST ("i") instead of TCG_CT_CONST_CMP ("C").
Adjust the constraint and make tcg_target_const_match use the
same sequence as tgen_cmp2: first check if the constant is a
valid operand for TSTEQ/TSTNE, then accept everything for 32-bit
non-test comparisons, finally check if the constant is a valid
operand for 64-bit non-test comparisons.
Reported-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
While hyperv.rst already has all currently implemented Hyper-V
enlightenments documented, it may be unclear what is the recommended set to
achieve the best result. Add the corresponding section to the doc.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240917160051.2637594-5-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
'hyperv_synic' test from KVM unittests was observed to be flaky on certain
hardware (hangs sometimes). Debugging shows that the problem happens in
hyperv_sint_route_new() when the test tries to set up a new SynIC
route. The function bails out on:
if (!synic->sctl_enabled) {
goto cleanup;
}
but the test writes to HV_X64_MSR_SCONTROL just before it starts
establishing SINT routes. Further investigation shows that
synic_update() (called from async_synic_update()) happens after the SINT
setup attempt and not before. Apparently, the comment before
async_safe_run_on_cpu() in kvm_hv_handle_exit() does not correctly describe
the guarantees async_safe_run_on_cpu() gives. In particular, async worked
added to a CPU is actually processed from qemu_wait_io_event() which is not
always called before KVM_RUN, i.e. kvm_cpu_exec() checks whether an exit
request is pending for a CPU and if not, keeps running the vCPU until it
meets an exit it can't handle internally. Hyper-V specific MSR writes are
not automatically trigger an exit.
Fix the issue by simply raising an exit request for the vCPU where SynIC
update was queued. This is not a performance critical path as SynIC state
does not get updated so often (and async_safe_run_on_cpu() is a big hammer
anyways).
Reported-by: Jan Richter <jarichte@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240917160051.2637594-4-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Windows with Hyper-V role enabled doesn't boot with 'hv-passthrough' when
no debugger is configured, this significantly limits the usefulness of the
feature as there's no support for subtracting Hyper-V features from CPU
flags at this moment (e.g. "-cpu host,hv-passthrough,-hv-syndbg" does not
work). While this is also theoretically fixable, 'hv-syndbg' is likely
very special and unneeded in the default set. Genuine Hyper-V doesn't seem
to enable it either.
Introduce 'skip_passthrough' flag to 'kvm_hyperv_properties' and use it as
one-off to skip 'hv-syndbg' when enabling features in 'hv-passthrough'
mode. Note, "-cpu host,hv-passthrough,hv-syndbg" can still be used if
needed.
As both 'hv-passthrough' and 'hv-syndbg' are debug features, the change
should not have any effect on production environments.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240917160051.2637594-3-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Putting HYPERV_FEAT_SYNDBG entry under "#ifdef CONFIG_SYNDBG" in
'kvm_hyperv_properties' array is wrong: as HYPERV_FEAT_SYNDBG is not
the highest feature number, the result is an empty (zeroed) entry in
the array (and not a skipped entry!). hyperv_feature_supported() is
designed to check that all CPUID bits are set but for a zeroed
feature in 'kvm_hyperv_properties' it returns 'true' so QEMU considers
HYPERV_FEAT_SYNDBG as always supported, regardless of whether KVM host
actually supports it.
To fix the issue, leave HYPERV_FEAT_SYNDBG's definition in
'kvm_hyperv_properties' array, there's nothing wrong in having it defined
even when 'CONFIG_SYNDBG' is not set. Instead, put "hv-syndbg" CPU property
under '#ifdef CONFIG_SYNDBG' to alter the existing behavior when the flag
is silently skipped in !CONFIG_SYNDBG builds.
Leave an 'assert' sentinel in hyperv_feature_supported() making sure there
are no 'holes' or improperly defined features in 'kvm_hyperv_properties'.
Fixes: d8701185f4 ("hw: hyperv: Initial commit for Synthetic Debugging device")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240917160051.2637594-2-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM commit 191c8137a939 ("x86/kvm: Implement HWCR support")
introduced support for emulating HWCR MSR.
Add support for QEMU to save/load this MSR for migration purposes.
Signed-off-by: Gao Shiyuan <gaoshiyuan@baidu.com>
Signed-off-by: Wang Liang <wangliang44@baidu.com>
Link: https://lore.kernel.org/r/20241009095109.66843-1-gaoshiyuan@baidu.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Following 5 bits in CPUID.7.2.EDX are supported by KVM. Add their
supports in QEMU. Each of them indicates certain bits of IA32_SPEC_CTRL
are supported. Those bits can control CPU speculation behavior which can
be used to defend against side-channel attacks.
bit0: intel-psfd
if 1, indicates bit 7 of the IA32_SPEC_CTRL MSR is supported. Bit 7 of
this MSR disables Fast Store Forwarding Predictor without disabling
Speculative Store Bypass
bit1: ipred-ctrl
If 1, indicates bits 3 and 4 of the IA32_SPEC_CTRL MSR are supported.
Bit 3 of this MSR enables IPRED_DIS control for CPL3. Bit 4 of this
MSR enables IPRED_DIS control for CPL0/1/2
bit2: rrsba-ctrl
If 1, indicates bits 5 and 6 of the IA32_SPEC_CTRL MSR are supported.
Bit 5 of this MSR disables RRSBA behavior for CPL3. Bit 6 of this MSR
disables RRSBA behavior for CPL0/1/2
bit3: ddpd-u
If 1, indicates bit 8 of the IA32_SPEC_CTRL MSR is supported. Bit 8 of
this MSR disables Data Dependent Prefetcher.
bit4: bhi-ctrl
if 1, indicates bit 10 of the IA32_SPEC_CTRL MSR is supported. Bit 10
of this MSR enables BHI_DIS_S behavior.
Signed-off-by: Chao Gao <chao.gao@intel.com>
Link: https://lore.kernel.org/r/20240919051011.118309-1-chao.gao@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When user sets tsc-frequency explicitly, the invtsc feature is actually
migratable because the tsc-frequency is supposed to be fixed during the
migration.
See commit d99569d9d8 ("kvm: Allow invtsc migration if tsc-khz
is set explicitly") for referrence.
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20240814075431.339209-10-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- CPUID.(EAX=07H,ECX=0H):EBX[bit 6]: x87 FPU Data Pointer updated only
on x87 exceptions if 1.
- CPUID.(EAX=07H,ECX=0H):EBX[bit 13]: Deprecates FPU CS and FPU DS
values if 1. i.e., X87 FCS and FDS are always zero.
Define names for them so that they can be exposed to guest with -cpu host.
Also define the bit field MACROs so that named cpu models can add it as
well in the future.
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20240814075431.339209-3-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, QEMU always constructs a all-zero CPUID entry for
CPUID[0xD 0x3f].
It's meaningless to construct such a leaf as the end of leaf 0xD. Rework
the logic of how subleaves of 0xD are constructed to get rid of such
all-zero value of subleaf 0x3f.
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20240814075431.339209-2-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add unimplemented-device blocks to the xilinx_zynq board
corresponding to various devices documented in the TRM
and in the device tree.
See: ug585-Zynq-7000-TRM manual B.3 (Module Summary)
Signed-off-by: Chao Liu <chao.liu@yeah.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: tweaked commit message. Removed the clearing of
the ignore_memory_transaction_failures flag]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Ensure the function names match.
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20241012-dma-v2-1-6afddf5f3c8d@daynix.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The ``-portrait`` and ``-rotate`` options were documented as only
working with the PXA LCD device, and all the machine types using
that display device were removed in 9.2.
These options were intended to simulate a mobile device being
rotated by the user, and had three effects:
* the display output was rotated by 90, 180 or 270 degrees
(implemented in the PXA display device models)
* the mouse/trackpad input was rotated the opposite way
(implemented in generic code)
* the machine model would signal to the guest about its
orientation
(implemented by e.g. the spitz machine model)
Of these three things, the input-rotation was coded without being
restricted to boards which supported the full set of device-rotation
handling, so in theory the options were usable on other machine
models with odd effects (rotating input but not display output). But
this was never intended or documented behaviour, so we can reasonably
drop these command line arguments without a formal deprecate-and-drop
cycle for them.
Remove the options, and their implementation and documentation.
Describe the removal in removed-features.rst.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20241003140010.1653808-7-peter.maydell@linaro.org
The ecc.c code was used only by the PXA2xx and OMAP2 SoC devices,
which we have removed, so it is now completely unused.
Note that hw/misc/eccmemctl.c does not in fact use any of the
code frome ecc.c, so that KConfig dependency was incorrect.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20241003140010.1653808-6-peter.maydell@linaro.org
The only PCMCIA subsystem was the PXA2xx SoC and the machines
using it, which have now been removed. Although in theory
we have a few machine types which have PCMCIA (e.g. kzm,
the strongarm machines, sh4's sh7750), none of those machines
implement their PCMCIA controller, and they're all old and
no longer very interesting machine types.
Rather than keeping all the PCMCIA code in-tree without any
active users of it, delete it. If we need PCMCIA in future
we can always resurrect it.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241003140010.1653808-5-peter.maydell@linaro.org
The DSCM-1XXXX microdrive device model was used only by the
XScale-based Zaurus machine types. Now they have been removed, we
can delete this device too.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20241003140010.1653808-4-peter.maydell@linaro.org
The MAX7310 GPIO controller was used only by the XScale-based Zaurus
machine types. Now they have been removed we can remove this device
model as well.
Because this device is an I2C device, in theory it could be created
by users on the command line for boards with a different I2c
controller, but we don't believe users are doing this -- it would be
impossible on the command line to connect up the GPIO inputs/outputs.
The only example a web search produces for "device max7310" is a user
trying to create this because they didn't realize that there was no
way to manipulate the GPIO lines.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20241003140010.1653808-3-peter.maydell@linaro.org
The MAX111X ADC device was used only by the XScale-based
Zaurus machine types. Now they have all been removed, we can
drop this device model too.
Because this device is an SSI device, in theory it could be created
by users on the command line for boards with a different SSI
controller, but we don't believe users are doing this -- it would be
impossible on the command line to connect up the GPIO inputs which
correspond to ADC inputs, or the GPIO output which is an interrupt
line. The only example a web search produces for "device max1111" or
"device max1110" is our own bug report
https://gitlab.com/qemu-project/qemu/-/issues/2228
where it's used as an example of a bogus command that causes an
assertion in an aspeed machine type that wasn't expecting anything
other than flash devices on its SMC bus.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20241003140010.1653808-2-peter.maydell@linaro.org
Pull in the kernel-doc API documentation into the lockcnt docs.
This requires us to fix one rST markup syntax error in the
header file comments.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20240816132212.3602106-8-peter.maydell@linaro.org
Currently the QemuLockCnt data structure and associated functions are
in the include/qemu/thread.h header. Move them to their own
qemu/lockcnt.h. The main reason for doing this is that it means we
can autogenerate the documentation comments into the docs/devel
documentation.
The copyright/author in the new header is drawn from lockcnt.c,
since the header changes were added in the same commit as
lockcnt.c; since neither thread.h nor lockcnt.c state an explicit
license, the standard default of GPL-2-or-later applies.
We include the new header (and the .c file, which was accidentally
omitted previously) in the "RCU" part of MAINTAINERS, since that
is where the lockcnt.rst documentation is categorized.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20240816132212.3602106-7-peter.maydell@linaro.org
Convert blkverify.txt to rST format.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-id: 20240816132212.3602106-3-peter.maydell@linaro.org
Convert blkdebug.txt to rST format. We put it into index-build.rst
because it falls under the "test" part of "QEMU Build and Test
System".
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-id: 20240816132212.3602106-2-peter.maydell@linaro.org
In commit b88cfee902 we defined masks for the IBRD and FBRD
integer and fractional baud rate divider registers, to prevent the
guest from writing invalid values which could cause division-by-zero.
Unfortunately we got the mask values the wrong way around: the FBRD
register is six bits and the IBRD register is 16 bits, not
vice-versa.
You would only run into this bug if you programmed the UART to a baud
rate of less than 9600, because for 9600 baud and above the IBRD
value will fit into 6 bits, as per the table in
https://developer.arm.com/documentation/ddi0183/g/programmers-model/register-descriptions/fractional-baud-rate-register--uartfbrd
The only visible effects would be that the value read back from
the register by the guest would be truncated, and we would
print an incorrect baud rate in the debug logs.
Cc: qemu-stable@nongnu.org
Fixes: b88cfee902 ("hw/char/pl011: Avoid division-by-zero in pl011_get_baudrate()")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2610
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Message-id: 20241007144732.2491331-1-peter.maydell@linaro.org
The OMAP interrupt controller code used to have an omap-intc
class and an omap2-intc class, which shared common code via
the abstract class common-omap-intc. Now we have deleted
omap2-intc, we don't need the separate abstract base class;
fold int into omap-intc.
Suggested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20241003135323.1653230-1-peter.maydell@linaro.org
The Allwinner A10 SPI controller is added to the Allwinner A10
description, so it is available when Cubieboard is emulated.
Update the documentation for Cubieboard to indicate SPI availability.
Signed-off-by: Strahinja Jankovic <strahinja.p.jankovic@gmail.com>
Message-id: 20241001221349.8319-3-strahinja.p.jankovic@gmail.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This patch implements Allwinner A10 SPI controller emulation.
Only master-mode functionality is implemented.
Since U-Boot and Linux SPI drivers for Allwinner A10 perform only
byte-wide CPU access (no DMA) to the transmit and receive registers of
the peripheral, the emulated controller does not implement DMA control,
and supports only byte-wide access to transmit and receive registers
(half-word and word accesses will be treated as byte accesses).
Signed-off-by: Strahinja Jankovic <strahinja.p.jankovic@gmail.com>
Message-id: 20241001221349.8319-2-strahinja.p.jankovic@gmail.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
For USART, GPIO and SYSCFG devices, check that clock frequency before
and after enabling the peripheral clock in RCC is correct.
Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20241003081105.40836-4-ines.varhol@telecom-paris.fr
[PMM: Added missing qtest_quit() call]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Expose the clock period via the QOM 'qtest-clock-period' property so it
can be used in QTests. This property is only accessible in QTests (not
via HMP).
Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20241003081105.40836-3-ines.varhol@telecom-paris.fr
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit creates a clock in STM32L4x5 SYSCFG and wires it up to the
corresponding clock from STM32L4x5 RCC.
Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Message-id: 20241003081105.40836-2-ines.varhol@telecom-paris.fr
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The result of 1 << regbit with regbit==31 has a 1 in the 32nd bit.
When cast to uint64_t (for further bitwise OR), the 32 most
significant bits will be filled with 1s. However, the documentation
states that the upper 32 bits of ICH_AP[0/1]R<n>_EL2 are reserved.
Add an explicit cast to match the documentation.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Cc: qemu-stable@nongnu.org
Fixes: c3f21b065a ("hw/intc/arm_gicv3_cpuif: Support vLPIs")
Signed-off-by: Alexandra Diupina <adiupina@astralinux.ru>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The result of 1 << regbit with regbit==31 has a 1 in the 32nd bit.
When cast to uint64_t (for further bitwise OR), the 32 most
significant bits will be filled with 1s. However, the documentation
states that the upper 32 bits of ICC_AP[0/1]R<n>_EL2 are reserved.
Add an explicit cast to match the documentation.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Cc: qemu-stable@nongnu.org
Fixes: 28cca59c46 ("hw/intc/arm_gicv3: Add NMI handling CPU interface registers")
Signed-off-by: Alexandra Diupina <adiupina@astralinux.ru>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The result of 1 << regbit with regbit==31 has a 1 in the 32nd bit.
When cast to uint64_t (for further bitwise OR), the 32 most
significant bits will be filled with 1s. However, the documentation
states that the upper 32 bits of ICH_AP[0/1]R<n>_EL2 are reserved.
Add an explicit cast to match the documentation.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Cc: qemu-stable@nongnu.org
Fixes: d2c0c6aab6 ("hw/intc/arm_gicv3: Handle icv_nmiar1_read() for icc_nmiar1_read()")
Signed-off-by: Alexandra Diupina <adiupina@astralinux.ru>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Add the reset and clock controller device to the stm32f405 SoC.
Signed-off-by: Roman Cardenas Rodriguez <rcardenas.rod@gmail.com>
[PMM: tweak commit message]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Generic RCC class for STM32 devices. It can be used for most of
the STM32 chips. Note that it only implements enable and reset
capabilities.
Signed-off-by: Roman Cardenas Rodriguez <rcardenas.rod@gmail.com>
[PMM: tweaked commit message, added MAINTAINERS lines]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The recently removed 'cheetah' machine was the single user
of the omap_uwire_attach() method. Remove it altogether with
the uWireSlave structure. Replace the send/receive callbacks
by Unimplemented logging.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This patch tests:
1. feasibility of removing mux which does not have frontends attached
or frontends were prior detached.
2. inability to remove mux which has frontends attached (mux is "busy")
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org
[ fixed *error leak ]
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20241014152408.427700-9-r.peniaev@gmail.com>
With bitset management now it becomes feasible to implement
the logic of detaching frontends from multiplexer.
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20241014152408.427700-8-r.peniaev@gmail.com>
Frontends can be attached and detached during run-time (although detach
is not implemented, but will follow). Counter variable of muxes is not
enough for proper attach/detach management, so this patch implements
bitset: if bit is set for the `mux_bitset` variable, then frontend
device can be found in the `backend` array (yes, huge confusion with
backend and frontends names).
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20241014152408.427700-7-r.peniaev@gmail.com>
Move away logic which attaches frontend device to a mux
from `char-fe.c` to actual `char-mux.c` implementation
and make it a separate function.
No logic changes are made.
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20241014152408.427700-6-r.peniaev@gmail.com>
There is no sense to keep `focus`, `mux_cnt`, `prod`, `cons`
and `tag` variables as signed, those represent either size,
either position in array, which both are unsigned.
`focus` member of `MuxChardev` is kept signed, because initially
set to -1.
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20241014152408.427700-5-r.peniaev@gmail.com>
Those are boolean variables, not signed integers.
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20241014152408.427700-4-r.peniaev@gmail.com>
`mux_cnt` struct member never goes negative or decrements,
so mux chardev can be !busy only when there are no
frontends attached. This patch fixes the always-true
check.
Fixes: a4afa548fc ("char: move front end handlers in CharBackend")
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20241014152408.427700-2-r.peniaev@gmail.com>
Paolo Bonzini