The qemu_plugin_{read,write} register API previously was inconsistent
with regard to its docstring (where a return value of both -1 and 0
would indicate an error) and to the memory read/write APIs, which
already return a boolean value to indicate success or failure.
Returning the number of bytes read or written is superfluous, as the
GByteArray* passed to the API functions already encodes the length.
See the linked thread for more details.
This patch moves from returning an int (number of bytes read/written) to
returning a bool from the register read/write API, bumps the plugin API
version, and adjusts plugins and tests accordingly.
Signed-off-by: Florian Hofhammer <florian.hofhammer@fhofhammer.de>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Link: https://lore.kernel.org/qemu-devel/f877dd79-1285-4752-811e-f0d430ff27fe@fhofhammer.de
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
The plugin API allows registration of callbacks for a variety of VCPU
related events, such as VCPU reset, idle and resume. In addition, we
recently introduced API for registering callbacks for discontinuity
events, specifically for interrupts, exceptions and host calls.
This change introduces the corresponding hooks called from target
specific code inside qemu.
Signed-off-by: Julian Ganz <neither@nut.email>
Message-ID: <20251027110344.2289945-10-alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
The plugin API allows registration of callbacks for a variety of VCPU
related events, such as VCPU reset, idle and resume. In addition to
those events, we recently defined discontinuity events, which include
traps.
This change introduces a function to register callbacks for these
events. We define one distinct plugin event type for each type of
discontinuity, granting fine control to plugins in term of which events
they receive.
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Julian Ganz <neither@nut.email>
Message-ID: <20251027110344.2289945-9-alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
This patch adds functions to the plugins API to allow plugins to read
and write memory via hardware addresses. The functions use the current
address space of the current CPU in order to avoid exposing address
space information to users. A later patch may want to add a function to
permit a specified address space, for example to facilitate
architecture-specific plugins that want to operate on them, for example
reading ARM secure memory.
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Rowan Hart <rowanbhart@gmail.com>
Message-ID: <20250624175351.440780-6-rowanbhart@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-ID: <20250627112512.1880708-10-alex.bennee@linaro.org>
This patch adds functionality to enforce the requested QEMU_PLUGIN_CB_
flags level passed when registering a callback function using the
plugins API. Each time a callback is about to be invoked, a thread-local
variable will be updated with the level that callback requested. Then,
called API functions (in particular, the register read and write API)
will call qemu_plugin_get_cb_flags() to check the level is at least the
level they require.
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Rowan Hart <rowanbhart@gmail.com>
Message-ID: <20250624175351.440780-4-rowanbhart@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-ID: <20250627112512.1880708-8-alex.bennee@linaro.org>
The build fails on Windows. Replace calls to Unix programs like ´cat´,
´sed´ and ´true´ with calls to ´python´ and wrap calls to
´os.path.relpath´ in try-except because it can fail when the two paths
are on different drives. Make sure to convert the Windows paths to Unix
paths to prevent warnings in generated files.
Signed-off-by: oltolm <oleg.tolmatcev@gmail.com>
Message-id: 20250612221521.1109-2-oleg.tolmatcev@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Coccinelle's indentation of virt_create_plic() results in a long line.
Avoid that by mimicking the old indentation manually.
Don't touch tests/tcg/mips/user/. I'm not sure these files are ours
to make style cleanups on. They might be imported third-party code,
which we should leave as is to not complicate future updates.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20250407082643.2310002-2-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
To move the main api.c to a single build compilation object we need to
start splitting out user and system specific code. As we need to grob
around host headers we move these particular helpers into the *-user
mode directories.
The binary/start/end/entry helpers are all NOPs for system mode.
While using the plugin-api.c.inc trick means we build for both
linux-user and bsd-user the BSD user-mode command line is still
missing -plugin. This can be enabled once we have reliable check-tcg
tests working for the BSDs.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20250304222439.2035603-27-alex.bennee@linaro.org>
There is very little in loader that is different between builds save
for a tiny user/system mode difference in the plugin_info structure.
Create two new files, user and system to hold mode specific helpers
and move loader into common_ss.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20250304222439.2035603-26-alex.bennee@linaro.org>
The declaration uses uint64_t for addr.
Fixes: 595cd9ce2e ("plugins: add plugin API to read guest memory")
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Replace g_strdup_printf("%s", value) -> g_strdup(value)
to avoid unnecessary string formatting.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
TB compile flags, tb_page_addr_t type, tb_cflags() and few
other methods are defined in "exec/translation-block.h".
All these files don't include "exec/translation-block.h" but
include "exec/exec-all.h" which include it. Explicitly include
"exec/translation-block.h" to be able to remove it from
"exec/exec-all.h" later when it won't be necessary. Otherwise
we'd get errors such:
accel/tcg/internal-target.h:59:20: error: a parameter list without types is only allowed in a function definition
59 | void tb_lock_page0(tb_page_addr_t);
| ^
accel/tcg/tb-hash.h:64:23: error: unknown type name 'tb_page_addr_t'
64 | uint32_t tb_hash_func(tb_page_addr_t phys_pc, vaddr pc,
| ^
accel/tcg/tcg-accel-ops.c:62:36: error: use of undeclared identifier 'CF_CLUSTER_SHIFT'
62 | cflags = cpu->cluster_index << CF_CLUSTER_SHIFT;
| ^
accel/tcg/watchpoint.c:102:47: error: use of undeclared identifier 'CF_NOIRQ'
102 | cpu->cflags_next_tb = 1 | CF_NOIRQ | curr_cflags(cpu);
| ^
target/i386/helper.c:536:28: error: use of undeclared identifier 'CF_PCREL'
536 | if (tcg_cflags_has(cs, CF_PCREL)) {
| ^
target/rx/cpu.c:51:21: error: incomplete definition of type 'struct TranslationBlock'
51 | cpu->env.pc = tb->pc;
| ~~^
system/physmem.c:2977:9: error: call to undeclared function 'tb_invalidate_phys_range'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
2977 | tb_invalidate_phys_range(addr, addr + length - 1);
| ^
plugins/api.c:96:12: error: call to undeclared function 'tb_cflags'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
96 | return tb_cflags(tcg_ctx->gen_tb) & CF_MEMI_ONLY;
| ^
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241114011310.3615-5-philmd@linaro.org>
Different code paths handle memory accesses:
- tcg generated code
- load/store helpers
- atomic helpers
This value is saved in cpu->neg.plugin_mem_value_{high,low}. Values are
written only for accessed word size (upper bits are not set).
Atomic operations are doing read/write at the same time, so we generate
two memory callbacks instead of one, to allow plugins to access distinct
values.
For now, we can have access only up to 128 bits, thus split this in two
64 bits words. When QEMU will support wider operations, we'll be able to
reconsider this.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240724194708.1843704-2-pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-5-alex.bennee@linaro.org>
A deadlock can be created if a new vcpu (a) triggers a scoreboard
reallocation, and another vcpu (b) wants to create a new scoreboard at
the same time.
In this case, (a) holds the plugin lock, and starts an exclusive
section, waiting for (b). But at the same time, (b) is waiting for
plugin lock.
The solution is to drop the lock before entering the exclusive section.
This bug can be easily reproduced by creating a callback for any tb
exec, that allocates a new scoreboard. In this case, as soon as we reach
more than 16 vcpus, the deadlock occurs.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2344
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240812220748.95167-2-pierrick.bouvier@linaro.org>
[AJB: tweak var position to meet coding style]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240813202329.1237572-22-alex.bennee@linaro.org>
Since commit 0082475e26 the plugin symbol list is unconditionally
added to the linker flags, leading to a build failure:
Undefined symbols for architecture arm64:
"_qemu_plugin_entry_code", referenced from:
<initial-undefines>
...
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
ninja: build stopped: subcommand failed.
Fix by restricting the whole meson file to the --enable-plugins
configure argument.
Fixes: 0082475e26 ("meson: merge plugin_ldflags into emulator_link_args")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2476
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240813112457.92560-1-philmd@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240813202329.1237572-9-alex.bennee@linaro.org>
As the list of options isn't fixed we do all the parsing by hand.
Without any named arguments we automatically fill the "file" option
with the value give so check if it is requesting help and dump some
basic usage text.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240729144414.830369-15-alex.bennee@linaro.org>
These serve the same purpose, except plugin_ldflags ends up in the linker
command line in a more roundabout way (through specific_ss). Simplify.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
