qemu-user can hang in a multi-threaded fork. One common
reason is that when creating a TB, between fork and exec
we manipulate a GTree whose memory allocator (GSlice) is
not fork-safe.
Although POSIX does not mandate it, the system's allocator
(e.g. tcmalloc, libc malloc) is probably fork-safe.
Fix some of these hangs by using QTree, which uses the system's
allocator regardless of the Glib version that we used at
configuration time.
Tested with the test program in the original bug report, i.e.:
```
void garble() {
int pid = fork();
if (pid == 0) {
exit(0);
} else {
int wstatus;
waitpid(pid, &wstatus, 0);
}
}
void supragarble(unsigned depth) {
if (depth == 0)
return ;
std::thread a(supragarble, depth-1);
std::thread b(supragarble, depth-1);
garble();
a.join();
b.join();
}
int main() {
supragarble(10);
}
```
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/285
Reported-by: Valentin David <me@valentindavid.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Emilio Cota <cota@braap.org>
Message-Id: <20230205163758.416992-3-cota@braap.org>
[rth: Add QEMU_DISABLE_CFI for all callback using functions.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
When dm_restrict is set, QEMU isn't permitted to update the XenStore node
to indicate its running status. Previously, the xs_write() call would fail
but the failure was ignored.
However, in refactoring to allow for emulated XenStore operations, a new
call to xs_open() was added. That one didn't fail gracefully, causing a
fatal error when running in dm_restrict mode.
Partially revert the offending patch, removing the additional call to
xs_open() because the global 'xenstore' variable is still available; it
just needs to be used with qemu_xen_xs_write() now instead of directly
with the xs_write() libxenstore function.
Also make the whole thing conditional on !xen_domid_restrict. There's no
point even registering the state change handler to attempt to update the
XenStore node when we know it's destined to fail.
Fixes: ba2a92db1f ("hw/xen: Add xenstore operations to allow redirection to internal emulation")
Reported-by: Jason Andryuk <jandryuk@gmail.com>
Co-developed-by: Jason Andryuk <jandryuk@gmail.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Tested-by: Jason Andryuk <jandryuk@gmail.com>
Message-Id: <1f141995bb61af32c2867ef5559e253f39b0949c.camel@infradead.org>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
This had been pulled in from hw/core/cpu.h,
but that will be removed.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230310195252.210956-6-richard.henderson@linaro.org>
[AJB: also syscall-trace.h]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230315174331.2959-16-alex.bennee@linaro.org>
Reviewed-by: Emilio Cota <cota@braap.org>
This had been pulled in via qemu/plugin.h from hw/core/cpu.h,
but that will be removed.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230310195252.210956-5-richard.henderson@linaro.org>
[AJB: add various additional cases shown by CI]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230315174331.2959-15-alex.bennee@linaro.org>
Reviewed-by: Emilio Cota <cota@braap.org>
Do this in cpu_tb_exec (normal exit) and cpu_loop_exit (exception),
adjacent to where we reset can_do_io.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1381
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230310195252.210956-2-richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230315174331.2959-12-alex.bennee@linaro.org>
Reviewed-by: Emilio Cota <cota@braap.org>
Move the tcg_temp_free_* and tcg_temp_ebb_new_* declarations
and inlines to the new header. These are private to the
implementation, and will prevent tcg_temp_free_* from creeping
back into the guest front ends.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
- split user and softmmu code
- use cleaner headers for tb_flush, target_ulong
- probe for gdb multiarch support at configure
- make syscall handling target independent
- add update guest debug of accel ops
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Merge tag 'pull-gdbstub-070323-3' of https://gitlab.com/stsquad/qemu into staging
gdbstub refactor:
- split user and softmmu code
- use cleaner headers for tb_flush, target_ulong
- probe for gdb multiarch support at configure
- make syscall handling target independent
- add update guest debug of accel ops
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# gpg: Signature made Tue 07 Mar 2023 20:45:23 GMT
# gpg: using RSA key 6685AE99E75167BCAFC8DF35FBD0DB095A9E2A44
# gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>" [full]
# Primary key fingerprint: 6685 AE99 E751 67BC AFC8 DF35 FBD0 DB09 5A9E 2A44
* tag 'pull-gdbstub-070323-3' of https://gitlab.com/stsquad/qemu: (30 commits)
gdbstub: move update guest debug to accel ops
gdbstub: Build syscall.c once
stubs: split semihosting_get_target from system only stubs
gdbstub: Adjust gdb_do_syscall to only use uint32_t and uint64_t
gdbstub: Remove gdb_do_syscallv
gdbstub: split out softmmu/user specifics for syscall handling
include: split target_long definition from cpu-defs
testing: probe gdb for supported architectures ahead of time
gdbstub: only compile gdbstub twice for whole build
gdbstub: move syscall handling to new file
gdbstub: move register helpers into standalone include
gdbstub: don't use target_ulong while handling registers
gdbstub: fix address type of gdb_set_cpu_pc
gdbstub: specialise stub_can_reverse
gdbstub: introduce gdb_get_max_cpus
gdbstub: specialise target_memory_rw_debug
gdbstub: specialise handle_query_attached
gdbstub: abstract target specific details from gdb_put_packet_binary
gdbstub: rationalise signal mapping in softmmu
gdbstub: move chunks of user code into own files
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Continuing the refactor of a48e7d9e52 (gdbstub: move guest debug support
check to ops) by removing hardcoded kvm_enabled() from generic cpu.c
code, and replace it with a property of AccelOpsClass.
Signed-off-by: Mads Ynddal <m.ynddal@samsung.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230207131721.49233-1-mads@ynddal.dk>
[AJB: add ifdef around update_guest_debug_ops, fix brace]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230302190846.2593720-27-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-30-richard.henderson@linaro.org>
This aids subsystems (like gdbstub) that want to trigger a flush
without pulling target specific headers.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230302190846.2593720-8-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-8-richard.henderson@linaro.org>
This header is now only for native Xen code, not PV backends that may be
used in Xen emulation. Since the toolstack libraries may depend on the
specific version of Xen headers that they pull in (and will set the
__XEN_TOOLS__ macro to enable internal definitions that they depend on),
the rule is that xen_native.h (and thus the toolstack library headers)
must be included *before* any of the headers in include/hw/xen/interface.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
There's no need for this to be in the Xen accel code, and as we want to
use the Xen console support with KVM-emulated Xen we'll want to have a
platform-agnostic version of it. Make it use GString to build up the
path while we're at it.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Since all temps allocated by guest front-ends are now TEMP_TB,
and we don't recycle TEMP_TB, there's no point in requiring
that the front-ends free the temps at all. Begin by dropping
the inner-most checks that all temps have been freed.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Fixes a bug in that we weren't reporting these changes.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Using an atomic write or read-write insn on ROM is basically
a happens-never case. Handle it via stop-the-world, which
will generate non-atomic serial code, where we can correctly
ignore the write while producing the correct read result.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
While changes are made to prot within tlb_set_page_full, they are
an implementation detail of softmmu. Retain the original for any
target use of probe_access_full.
Fixes: 4047368938 ("accel/tcg: Introduce tlb_set_page_full")
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
When CONFIG_PROFILER is set there are various undefined references to
profile_getclock. Include the header which defines this function.
For example:
../tcg/tcg.c: In function ‘tcg_gen_code’:
../tcg/tcg.c:4905:51: warning: implicit declaration of function ‘profile_getclock’ [-Wimplicit-function-declaration]
4905 | qatomic_set(&prof->opt_time, prof->opt_time - profile_getclock());
| ^~~~~~~~~~~~~~~~
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230303084948.3351546-1-rjones@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Here we are creating a temp whose value needs to be replaced,
but always storing NULL into CPUState.plugin_mem_cbs.
Use tcg_constant_ptr(0) explicitly.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
All of these uses have quite local scope.
Avoid tcg_const_*, because we haven't added a corresponding
interface for TEMP_EBB. Use explicit tcg_gen_movi_* instead.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Write back the number of insns that we attempt to translate,
so that if we longjmp out we have a more accurate limit for
the next attempt. This results in fewer restarts when some
limit is consumed by few instructions.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In preparation for returning the number of insns generated
via the same pointer. Adjust only the prototypes so far.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230227135202.9710-13-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
tb-jmp-cache.h contains a few small functions that only exist to hide a
CF_PCREL check, however the caller often already performs such a check.
This patch moves CF_PCREL checks from the callee to the caller, and also
removes these functions which now only hide an access of the jmp-cache.
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230227135202.9710-12-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230227135202.9710-5-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The default number of PIRQs is set to 256 to avoid issues with 32-bit MSI
devices. Allow it to be increased if the user desires.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
This just initializes the basic Xen support in KVM for now. Only permitted
on TYPE_PC_MACHINE because that's where the sysbus devices for Xen heap
overlay, event channel, grant tables and other stuff will exist. There's
no point having the basic hypercall support if nothing else works.
Provide sysemu/kvm_xen.h and a kvm_xen_get_caps() which will be used
later by support devices.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Also set XEN_ATTACH mode in xen_init() to reflect the truth; not that
anyone ever cared before. It was *only* ever checked in xen_init_pv()
before.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Change to match the recent change to probe_access_flags.
All existing callers updated to supply 0, so no change in behaviour.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
probe_access_flags() as it is today uses probe_access_full(), which in
turn uses probe_access_internal() with size = 0. probe_access_internal()
then uses the size to call the tlb_fill() callback for the given CPU.
This size param ('fault_size' as probe_access_internal() calls it) is
ignored by most existing .tlb_fill callback implementations, e.g.
arm_cpu_tlb_fill(), ppc_cpu_tlb_fill(), x86_cpu_tlb_fill() and
mips_cpu_tlb_fill() to name a few.
But RISC-V riscv_cpu_tlb_fill() actually uses it. The 'size' parameter
is used to check for PMP (Physical Memory Protection) access. This is
necessary because PMP does not make any guarantees about all the bytes
of the same page having the same permissions, i.e. the same page can
have different PMP properties, so we're forced to make sub-page range
checks. To allow RISC-V emulation to do a probe_acess_flags() that
covers PMP, we need to either add a 'size' param to the existing
probe_acess_flags() or create a new interface (e.g.
probe_access_range_flags).
There are quite a few probe_* APIs already, so let's add a 'size' param
to probe_access_flags() and re-use this API. This is done by open coding
what probe_access_full() does inside probe_acess_flags() and passing the
'size' param to probe_acess_internal(). Existing probe_access_flags()
callers use size = 0 to not change their current API usage. 'size' is
asserted to enforce single page access like probe_access() already does.
No behavioral changes intended.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-Id: <20230223234427.521114-2-dbarboza@ventanamicro.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Copy part of the description of commit f7b78602fd ("accel/tcg:
Add cluster number to TCG TB hash") in tcg_cpu_init_cflags(),
improving a bit CPUState::cluster_index documentation.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20230216142338.82982-2-philmd@linaro.org>
replay API is used deeply within TCG common code (common to user
and system emulation). Unfortunately "sysemu/replay.h" requires
some QAPI headers for few system-specific declarations, example:
void replay_input_event(QemuConsole *src, InputEvent *evt);
Since commit c2651c0eaa ("qapi/meson: Restrict UI module to system
emulation and tools") the QAPI header defining the InputEvent is
not generated anymore.
To keep it simple, extract the 'core' replay prototypes to a new
"exec/replay-core.h" header which we include in the TCG code that
doesn't need the rest of the replay API.
Reviewed-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Message-Id: <20221219170806.60580-5-philmd@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Silent when compiling with -Wextra:
../accel/kvm/kvm-all.c:2291:17: warning: missing field 'num' initializer [-Wmissing-field-initializers]
{ NULL, }
^
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221220143532.24958-3-philmd@linaro.org>
Unused since introduction in commit 04b0de0ee8
("xen: factor out common functions").
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Paul Durrant <paul@xen.org>
Message-Id: <20230215153451.30626-1-philmd@linaro.org>
Since commit a0e61807a3 ("qapi: Remove QMP events and commands from
user-mode builds") we don't generate the "qapi-commands-machine.h"
header in a user-emulation-only build.
Rename 'hmp.c' as 'monitor.c' and move the QMP functions from
cpu-exec.c (which is always compiled) to monitor.c (which is only
compiled when system-emulation is selected).
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20221219170806.60580-4-philmd@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20221219170806.60580-2-philmd@linaro.org>
Both insert/remove_breakpoint() handlers are used in system and
user emulation. We can not use the 'hwaddr' type on user emulation,
we have to use 'vaddr' which is defined as "wide enough to contain
any #target_ulong virtual address".
gdbstub.c doesn't require to include "exec/hwaddr.h" anymore.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20221216215519.5522-4-philmd@linaro.org>
If an instruction straddles a page boundary, and the first page
was ram, but the second page was MMIO, we would abort. Handle
this as if both pages are MMIO, by setting the ram_addr_t for
the first page to -1.
Reported-by: Sid Manning <sidneym@quicinc.com>
Reported-by: Jørgen Hansen <Jorgen.Hansen@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit was created with scripts/clean-includes.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20230202133830.2152150-19-armbru@redhat.com>
This will allow targets to avoid rolling their own.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These are not yet considering atomicity of the 16-byte value;
this is a direct replacement for the current target code which
uses a pair of 8-byte operations.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
After commit 4e4fa6c12d ("accel/tcg: Complete cpu initialization
before registration"), it looks the CPUJumpCache pointer can be NULL.
This causes a SIGSEV when running debug-wp-migration kvm unit test.
At the first place it should be clarified why this TCG code is called
with KVM acceleration. This may hide another bug.
Fixes: 4e4fa6c12d ("accel/tcg: Complete cpu initialization before registration")
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Message-Id: <20230203171510.2867451-1-eric.auger@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This moves these commands from MAINTAINERS section "QMP" to new
section "Stats". Status is Orphan. Volunteers welcome!
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-23-armbru@redhat.com>
There are actually a whole bunch of helpers that don't affect memory
that we shouldn't instrument. They are helpfully identified by the
TCG_CALL_NO_SIDE_EFFECTS flag which marks out lookup_tb_ptr as well as
a lot of the maths helpers. To avoid the string compare we introduce a
new flag for plugin internals so we skip that too.
Related: #1381
Signed-off-by: Emilio Cota <cota@braap.org>
Message-Id: <20230108164731.61469-4-cota@braap.org>
[AJB: updated to skip all no SE plugins, add flag for plugin helper]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230124180127.1881110-34-alex.bennee@linaro.org>
We were mistakenly checking tcg_ctx->plugin_insn as a canary to know
whether the TB had emitted helpers that might have accessed memory.
The problem is that tcg_ctx->plugin_insn gets updated on every
instruction in the TB, which results in us wrongly performing the
optimization (i.e. not clearing cpu->plugin_mem_cbs) way too often,
since it's not rare that the last instruction in the TB doesn't
use helpers.
Fix it by tracking a per-TB canary.
While at it, expand documentation.
Related: #1381
Signed-off-by: Emilio Cota <cota@braap.org>
Message-Id: <20230108164731.61469-2-cota@braap.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-32-alex.bennee@linaro.org>
